New piperazine compound and use thereof as a hcv polymerase inhibitor

Abstract

The present invention relates to a compound represented by the following formula [I] wherein each symbol is as defined in the specification, or a pharmaceutically acceptable salt thereof, or a solvate thereof and an anti-HCV agent and an HCV polymerase inhibitor containing this compound. The compound of the present invention shows an anti-HCV activity based on the HCV polymerase inhibitory activity, and useful as an agent for the prophylaxis or treatment of hepatitis C.

1 .- 14 . (canceled) 
     
     
         15 . A compound represented by the following formula [I-A] or a pharmaceutically acceptable salt thereof, or a solvate thereof: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following up A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         q1 is an integer of 1 to 4, 
         group A: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         —NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted b 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogeno C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         16 . A compound represented by the following formula [I-B] or a pharmaceutically acceptable salt thereof, or a solvate thereof: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group A: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         —NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogen C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         17 . A compound represented by the following formula [I-C] or a pharmaceutically acceptable salt thereof, or a solvate thereof: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group A: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         —NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogeno C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         18 . A compound represented by the following formula [I-D1] or a pharmaceutically acceptable salt thereof, or a solvate thereof: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         ring B1 is a phenyl group optionally substituted by 1 to 5 substituents selected from group A), and 
         ring C2 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A′ (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group A′: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         —NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from group C, 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from group C, 
         group A: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the follow group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogeno C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         19 . The compound of any one of  claims 15  to  18 , wherein ring A is a phenyl group optionally substituted by 1 to 5 substituents selected from group A, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         20 . The compound of any one of  claims 15  to  18 , wherein n is 1, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         21 . The compound of any one of  claims 15  to  17 , wherein the ring B is a phenyl group optionally substituted by 1 to 5 substituents selected from group A, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         22 . The compound of any one of  claims 15  to  17 , wherein the ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A, and the heterocyclic group is selected from the group consisting of piperidinyl group, morpholinyl group, pyrrolidinyl group, piperazinyl group, thiazolyl group, isothiazolyl group, pyrazolyl group, imidazolyl group, triazolyl group, tetrazolyl group, oxazolyl group, isoxazolyl group, thiadiazolyl group, oxadiazolyl group, pyridyl group and pyrimidinyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         23 . The compound of  claim 16 , wherein the ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A, and the heterocyclic group is selected from the group consisting of thiazolyl group, isothiazolyl group, isoxazolyl group, thiadiazolyl group, oxadiazolyl group, pyrazolyl group, triazolyl group, tetrazolyl group, pyridyl group and pyrimidinyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         24 . The compound of  claim 17 , wherein the ring C1 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A, and the heterocyclic group is selected from the group consisting of piperidinyl group, morpholinyl group, pyrrolidinyl group, piperazinyl group, pyrazolyl group, imidazolyl group, triazolyl group, tetrazolyl group, isoxazolyl group, pyridyl group and pyrimidinyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         25 . The compound of  claim 18 , wherein the ring C2 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A′, and the heterocyclic group is selected from the group consisting of imidazolinyl group, thiazolinyl group, oxazolinyl group, thienyl group, dioxopyrrolidinyl group, dioxopyrrolinyl group, oxopyrrolidinyl group, oxothiadiazolinyl group, tetrahydrobenzothiazolyl group, thiazolyl group, thiadiazolyl group, pyrazolyl group, imidazolyl group, triazolyl group, oxazolyl group, pyridyl group, pyrimidinyl group, pyrazinyl group, pyridazinyl group, quinolyl group,
 [1,5]naphthyridinyl group, 
 [1,6]naphthyridinyl group, 
 oxopiperidinyl group, 
 oxodihydropyridinyl group, 
 [1,2,4]triazolo[1,5-a]pyrimidinyl group, 
 benzimidazolyl group, 
 imidazo[4,5-c]pyridinyl group, 
 quinoxalinyl group, 
 pyrido[2,3-b]pyrazinyl group, 
 pyrido[3,4-b]pyrazinyl group, 
 pteridinyl group, 
 pyrazino[2,3-b]pyrazinyl group, 
 imidazo[4,5-b]pyrazinyl group, 
 2,2-dioxo-1,2,3,4-tetrahydropyrazino[2,3-c][1,2,6]thiadiazinyl group, 
 2-oxo-1,4-dihydropyrazino[2,3-d][1,3]oxazinyl group, 
 2-oxo-2,3-dihydroimidazo[4,5-b]pyrazinyl group, 
 [1,2,5]thiadiazolo[3,4-b]pyrazinyl group, 
 benzothiazolyl group, 
 4,5,6,7-tetrahydrobenzothiazolyl group, 
 thiazolo[5,4-b]pyridinyl group, 
 thiazolo[5,4-c]pyridinyl group, 
 thiazolo[4,5-d]pyrimidinyl group, 
 thiazolo[5,4-d]pyrimidinyl group, 
 thiazolo[4,5-d]pyridazinyl group, 
 thiazolo[4,5-b]pyrazinyl group, 
 thiazolo[4,5-d][1,2,3]triazinyl group, 
 5-oxo-4,5-dihydrothiazolo[5,4-b]pyridinyl group, 
 pyrazolo[3,4-d]thiazolyl group, 
 4,6-dioxo-5,6-dihydropyrrolo[3,4-d]thiazolyl group, 
 4,5,6,7-tetrahydrothiazolo[5,4-c]pyridinyl group, 
 4-oxo-4,5,6,7-tetrahydrothiazolo[5,4-c]pyridinyl group, 
 4-oxo-4,5-dihydrothiazolo[5,4-c]pyridinyl group, 
 7-oxo-6,7-dihydrothiazolo[4,5-d]pyrimidinyl group, 
 4-oxo-4,5-dihydrothiazolo[4,5-d]pyridazinyl group, 
 7-oxo-6,7-dihydrothiazolo[4,5-d]pyridazinyl group, 
 4,7-dioxo-4,5,6,7-tetrahydrothiazolo[4,5-d]pyridazinyl group, 
 4-oxo-3,4-dihydrothiazolo[4,5-d][1,2,3]triazinyl group, 
 5-oxo-[1,3,4]thiadiazolo[3,2-a]pyrimidinyl group, 
 7-oxo-[1,3,4]thiadiazolo[3,2-a]pyrimidinyl group, 
 4-oxo-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazinyl group, 
 [1,2,4]triazolo[3,4-b][1,3,4]thiadiazolyl group, and 
 indenothiazolyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
 
     
     
         26 . The compound of  claim 25 , wherein the ring C2 is a thiazol-2-yl group optionally substituted by 1 to 5 substituents selected from group A′, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         27 . The compound of  claim 25 , wherein the ring C2 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A′, and the heterocyclic group is selected from the group consisting of
 benzothiazol-2-yl group, 
 4,5,6,7-tetrahydrobenzothiazol-2-yl group, 
 thiazolo[5,4-b]pyridin-2-yl group, 
 thiazolo[5,4-c]pyridin-2-yl group, 
 thiazolo[4,5-d]pyrimidin-2-yl group, 
 thiazolo[5,4-d]pyrimidin-2-yl group, 
 thiazolo[4,5-d]pyridazin-2-yl group, 
 thiazolo[4,5-b]pyrazin-2-yl group, 
 thiazolo[4,5-d][1,2,3]triazin-6-yl group, 
 5-oxo-4,5-dihydrothiazolo[5,4-b]pyridin-2-yl group, 
 1H-pyrazolo[3,4-d]thiazol-5-yl group, 
 4,6-dioxo-5,6-dihydro-4H-pyrrolo[3,4-d]thiazol-2-yl group, 
 4,5,6,7-tetrahydrothiazolo[5,4-c]pyridin-2-yl group, 
 4-oxo-4,5,6,7-tetrahydrothiazolo[5,4-c]pyridin-2-yl group, 
 4-oxo-4,5-dihydrothiazolo[5,4-c]pyridin-2-yl group, 
 7-oxo-6,7-dihydrothiazolo[4,5-d]pyrimidin-2-yl group, 
 4-oxo-4,5-dihydrothiazolo[4,5-d]pyridazin-2-yl group, 
 7-oxo-6,7-dihydrothiazolo[4,5-d]pyridazin-2-yl group, 
 4,7-dioxo-4,5,6,7-tetrahydrothiazolo[4,5-d]pyridazin-2-yl group, 
 4-oxo-3,4-dihydrothiazolo[4,5-d][1,2,3]triazin-6-yl group, 
 5-oxo-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl group, 
 7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl group, 
 4-oxo-4H-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-7-yl group, 
 [1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl group, and 
 indenothiazolyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
 
     
     
         28 . The compound of  claim 25 , wherein the ring C2 is a pyrazin-2-yl group optionally substituted by 1 to 5 substituents selected from group A′, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
     
     
         29 . The compound of  claim 25 , wherein the ring C2 is a heterocyclic group optionally substituted by 1 to 5 substituents selected from group A′, and the heterocyclic group is selected from the group consisting of
 quinoxalin-2-yl group, 
 pyrido[2,3-b]pyrazin-2-yl group, 
 pyrido[2,3-b]pyrazin-3-yl group, 
 pyrido[3,4-b]pyrazin-2-yl group, 
 pteridin-6-yl group, 
 pteridin-7-yl group, 
 pyrazino[2,3-b]pyrazin-2-yl group, 
 1H-imidazo[4,5-b]pyrazin-5-yl group, 
 2,2-dioxo-1,2,3,4-tetrahydropyrazino[2,3-c][1,2,6]thiadiazin-7-yl group, 
 2-oxo-1,4-dihydro-2H-pyrazino[2,3-d][1,3]oxazin-7-yl group, 
 2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyrazin-5-yl group, and 
 [1,2,5]thiadiazolo[3,4-b]pyrazinyl group, or a pharmaceutically acceptable salt thereof, or a solvate thereof. 
 
     
     
         30 . The compound of  claim 16 , which is selected from the group consisting of
 (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyridin-4-ylamide,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyridin-3-ylamide,   (R)-4-(4-propyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyridin-4-ylamide,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyrimidin-4-ylamide,   4-{[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-pyridine-2-carboxylic acid tert-butyl ester,   4-{[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-pyridine-2-carboxylic acid hydrochloride,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyridin-4-ylamide,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-[1,3,4]thiadiazol-2-ylamide,   5-{[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-[1,3,4]oxadiazole-2-carboxylic acid ethyl ester,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-pyridin-4-ylamide,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-isopropyl-benzylamide) 1-[1,3,4]oxadiazol-2-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-propyl-benzylamide) 1-pyridin-4-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-(4-propyl-benzylamide) 1-[1,3,4]thiadiazol-2-ylamide,   (2-{[(R)-3-(4-propyl-benzyl carbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-thiazol-4-yl)-acetic acid ethyl ester,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-{[4-(2-morpholin-4-yl-2-oxo-ethyl)-thiazol-2-yl]-amide} 3-(4-propyl-benzylamide),   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-{[4-(2-hydroxy-ethyl)-thiazol-2-yl]-amide} 3-(4-propyl-benzylamide),   5-{[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-[1,3,4]thiadiazole-2-carboxylic acid ethyl ester,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(5-hydroxymethyl-[1,3,4]thiadiazol-2-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(5-acetyl-[1,3,4]thiadiazol-2-yl)-amide] 3-[4-(1,1-difluoro-propyl)-benzylamide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[5-(1-hydroxy-1-methyl-ethyl)-[1,3,4]thiadiazol-2-yl]-amide},   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(5-methyl-[1,3,4]thiadiazol-2-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(5-trifluoromethyl-[1,3,4]thiadiazol-2-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2-methoxy-pyridin-4-yl)-amide],   4-{[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-pyridine-2-carboxylic acid tert-butyl ester,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[5-((R)-3-hydroxy-pyrrolidine-1-carbonyl)-[1,3,4]thiadiazol-2-yl]-amide},   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[5-(4-hydroxy-piperidine-1-carbonyl)-[1,3,4]thiadiazol-2-yl]-amide},   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[5-(morpholine-4-carbonyl)-[1,3,4]thiadiazol-2-yl]-amide},   4-{[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1-carbonyl]-amino}-pyridine-2-carboxylic acid,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(2-carbamoyl-pyridin-4-yl)-amide] 3-[4-(1,1-difluoro-propyl)-benzylamide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2-dimethylcarbamoyl-pyridin-4-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2-hydroxymethyl-pyridin-4-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(2-cyclopropylcarbamoyl-pyridin-4-yl)-amide] 3-[4-(1,1-difluoro-propyl)-benzylamide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[2-(morpholine-4-carbonyl)-pyridin-4-yl]-amide},   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[2-(pyrrolidine-1-carbonyl)-pyridin-4-yl]-amide},   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(2-chloro-pyridin-4-yl)-amide] 3-[4-(1,1-difluoro-propyl)-benzylamide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-thiazol-4-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(5-methyl-isoxazol-3-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(3-methyl-[1,2,4]thiadiazol-5-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(3-methyl-isoxazol-5-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[1,2,4]triazol-4-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(5-methyl-[1,3,4]thiadiazol-2-yl)-amide] 3-(4-pentafluoroethyl-benzylamide),   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(3-methyl-isothiazol-5-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-thiazol-2-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2-trifluoromethyl-pyridin-4-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(1H-[1,2,4]triazol-3-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2H-tetrazol-5-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(2-methyl-thiazol-4-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-[(1-methyl-1H-pyrazol-3-yl)-amide],   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-thiazol-5-ylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 3-[4-(1,1-difluoro-propyl)-benzylamide] 1-{[4-(1-hydroxy-1-methyl-ethyl)-thiazol-2-yl]-amide}, and   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1,3-dicarboxylic acid 1-[(5-bromo-[1,3,4]thiadiazol-2-yl)-amide] 3-(4-trifluoromethoxy-benzylamide),   or a pharmaceutically acceptable salt thereof, or a solvate thereof.   
     
     
         31 . The compound of  claim 17 , which is selected from the group consisting of
 (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   1-(4-iodo-benzenesulfonyl)-4-(2-piperidin-1-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   1-(4-iodo-benzenesulfonyl)-4-(2-morpholin-4-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   1-(4-iodo-benzenesulfonyl)-4-(2-pyridin-2-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   1-(4-iodo-benzenesulfonyl)-4-(2-pyridin-3-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-1-(4-iodo-benzenesulfonyl)-4-(2-piperidin-1-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-1-(4-iodo-benzenesulfonyl)-4-(2-pyrrolidin-1-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-1-(4-iodo-benzenesulfonyl)-4-(2-morpholin-4-yl-acetyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-4-(2-pyridin-3-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-morpholin-4-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-1H-imidazol-4-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-imidazol-1-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-[1,2,3]triazol-1-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-pyrazol-1-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-[1,2,4]triazol-1-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-[1,2,4]triazol-4-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-[1,2,3]triazol-2-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-tetrazol-1-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-1H-tetrazol-5-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2-tetrazol-2-yl-acetyl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (2-{2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-2H-tetrazol-5-yl)-acetic acid ethyl ester,   (2-{2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-2H-tetrazol-5-yl)-acetic acid,   (1-{2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-1H-tetrazol-5-yl)-acetic acid ethyl ester,   (1-{2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-1H-tetrazol-5-yl)-acetic acid,   1-(4-iodo-benzenesulfonyl)-4-[2-(4-methyl-piperazin-1-yl)-acetyl]-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-dimethylamino-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-cyclopropyl-benzylamide,   (2-{2-oxo-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-ethyl}-2H-tetrazol-5-yl)-acetic acid ethyl ester,   (R)-4-[2-(5-methyl-tetrazol-1-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-[2-(5-methyl-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-tetrazol-2-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-tetrazol-1-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-imidazol-1-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-tetrazol-1-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (2-{2-oxo-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-ethyl}-2H-tetrazol-5-yl)-acetic acid,   (2-{2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-2H-tetrazol-5-yl)-acetic acid ethyl ester,   (R)-4-[2-(5-methyl-tetrazol-1-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(5-methyl-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(5-phenyl-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(3-methyl-isoxazol-5-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(1-methyl-1H-imidazol-4-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(2-pyridin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(2-methyl-2H-tetrazol-5-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(1-methyl-1H-tetrazol-5-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (5-{2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-tetrazol-2-yl)-acetic acid ethyl ester,   (5-{2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-2-oxo-ethyl}-tetrazol-1-yl)-acetic acid ethyl ester,   (R)-4-[2-(5-isopropyl-tetrazol-1-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(5-isopropyl-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-{2-[5-(2-morpholin-4-yl-2-oxo-ethyl)-tetrazol-2-yl]-acetyl}-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(5-methyl-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-pentafluoroethyl-benzylamide,   (R)-4-(2-pyrimidin-4-yl-acetyl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[2-(5-amino-tetrazol-2-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide, and   (R)-4-[2-(5-amino-tetrazol-1-yl)-acetyl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   or a pharmaceutically acceptable salt thereof, or a solvate thereof.   
     
     
         32 . The compound of  claim 18 , which is selected from the group consisting of
 2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid tert-butyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(5-carbamoyl)-4-methyl-thiazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   (R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-[(6-isopropyl-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(2-fluoro-4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-(4,5-dihydro-1H-imidazol-2-yl)-1-(4-isopropyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   4-(4,5-dihydro-thiazol-2-yl)-1-(4-isopropyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   1-(4-isopropyl-benzenesulfonyl)-4-(4-methyl-thiazol-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   4-(4,5-dihydro-oxazol-2-yl)-1-(4-isopropyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   4-benzothiazol-2-yl-1-(4-isopropyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   1-(4-isopropyl-benzenesulfonyl)-4-(4-phenyl-thiazol-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   (R)-4-(2,5-dioxo-pyrrolidin-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2,5-dioxo-4-phenyl-2,5-dihydro-1H-pyrrol-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   4-(8H-indeno[1,2-d]thiazol-2-yl)-1-(4-isopropyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   1-(4-isopropyl-benzenesulfonyl)-4-(4,5,6,7-tetrahydro-benzothiazol-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   2-[4-(4-isopropyl-benzenesulfonyl)-3-(4-trifluoromethyl-benzylcarbamoyl)-piperazin-1-yl]-thiazole-4-carboxylic acid ethyl ester,   2-[4-(4-isopropyl-benzenesulfonyl)-3-(4-trifluoromethyl-benzylcarbamoyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   (R)-4-(4,5-dihydro-thiazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(4-methyl-thiazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-benzothiazol-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid methyl ester,   {2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazol-4-yl}-acetic acid methyl ester,   {2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazol-4-yl}-acetic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid ethyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid methyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid methyl ester,   6-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-nicotinic acid methyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid tert-butyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-tri-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid tert-butyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-hydroxy-2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-pyrimidine-5-carboxylic acid ethyl ester,   6-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-nicotinic acid tert-butyl ester,   6-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-nicotinic acid trifluoroacetate,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-2-methyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid tert-butyl ester,   2-[(R)-3-(4-isopropyl-2-methyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(5-carbamoyl-4-methyl-thiazol-2-yl)-1-(4-propyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   2-[(R)-3-(4-isopropyl-2-methyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-pyrimidine-5-carboxylic acid benzyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-pyrimidine-5-carboxylic acid methyl ester,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-pyrimidine-5-carboxylic acid,   4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   (R)-4-(5-carbamoyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   4-methyl-2-[(R)-3-(2-methyl-4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-pyrimidine-5-carboxylic acid,   2-[(R)-3-(4-dimethylamino-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-4-(4-isopropyl-benzenesulfonyl)-3-(4-isopropyl-benzyl carbamoyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(2-oxo-pyrrolidin-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-isonicotinic acid trifluoroacetate,   (R)-4-(1-methyl-1H-imidazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(1H-imidazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(4-methyl-5-methylcarbamoyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(5-dimethylcarbamoyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   2-[(R)-3-(4-cyclopropyl-2-methyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-hydroxy-2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-pyrimidine-5-carboxylic acid,   ({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-acetic acid tert-butyl ester,   3-({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-propionic acid tert-butyl ester,   ({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-acetic acid,   3-({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-propionic acid,   (R)-4-(5-nitro-2H-[1,2,4]triazol-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   4-ethyl-2-[(R)-3-(2-methyl-4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-2-methyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-methyl-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-ethyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(5-amino-2H-[1,2,4]triazol-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-2-({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-propionic acid,   (S)-2-({2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carbonyl}-amino)-propionic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-4-methyl-oxazole-5-carboxylic acid trifluoroacetate,   (R)-4-(5-bromo-2H-[1,2,4]triazol-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(2H-[1,2,4]triazol-3-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   6-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid,   (R)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3,5′-dicarboxylic acid 5′-amide 3-(4-isopropyl-benzylamide),   4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-dimethylamino-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid hydrochloride,   3-{2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-4-yl}-propionic acid,   2-[(R)-3-(4-cyclopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-5′-carboxylic acid,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-[(6-dimethylamino-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-methyl-2-[(R)-3-[(6-propyl-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-[(6-azetidin-1-yl-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   4-methyl-2-[(R)-3-[(6-pyrrolidin-1-yl-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-4-methoxymethyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-azetidin-1-yl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-3-(4-dimethylamino-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-benzylcarbamoyl-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(5-carbamoyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-3-[(6-dimethylamino-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-3-[(6-isopropyl-pyridin-3-ylmethyl)-carbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   4-methyl-2-[(R)-3-(4-pyrrolidin-1-yl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid,   4-methyl-2-[(R)-3-phenethylcarbamoyl-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   (R)-6′-amino-3′-chloro-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   (R)-6′-bromo-3′-chloro-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   (R)-3-(4-isopropyl-benzylcarbamoyl)-3′,6′-dimethyl-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-6′-amino-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   2-[(R)-3-[4-(ethyl-methyl-amino)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   2-[(R)-3-(4-diethylamino-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   5-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2H-pyrazole-3-carboxylic acid,   4-chloro-5-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2H-pyrazole-3-carboxylic acid,   (R)-3-(4-isopropyl-benzylcarbamoyl)-3′-methyl-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   (R)-3-(2-methyl-4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-5-methyl-thiazole-4-carboxylic acid,   5-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-1-methyl-1H-pyrazole-3-carboxylic acid,   (R)-4-(4-propyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-3-(2-methyl-4-propyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-(4-ethoxy-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-6′-amino-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-trifluoromethyl-thiazole-5-carboxylic acid ethyl ester,   5-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-2-methyl-2H-pyrazole-3-carboxylic acid,   (R)-4-(5-methanesulfonylaminocarbonyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(5-methanesulfonylaminocarbonyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-6′-methyl-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   2-[(R)-3-(4-methoxymethyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(5-hydroxymethyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-trifluoromethyl-thiazole-5-carboxylic acid,   (R)-4-(6-hydroxy-5-methyl-pyridazin-3-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(5-amino-pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-5′-amino-4-(4-trifluoromethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-isopropyl-benzylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-3-(4-methoxymethyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-5′-carboxylic acid,   (R)-3-(2-chloro-4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-4-(4-ethyl-benzenesulfonyl)-5′-hydroxymethyl-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-3-(2-chloro-4-propyl-benzylcarbamoyl)-4-(4-ethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   4-methyl-6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid methyl ester,   4-methyl-6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid,   {4-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl}-pyrazol-1-yl]-acetic acid,   4-methyl-6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid amide   4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(3-propyl-4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   (R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-4-(5-dimethylaminomethyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4-methyl-5-methylaminomethyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-6′-amino-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   2-[(R)-4-(3-fluoro-4-trifluoromethoxy-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid,   (R)-4-(4-hydroxymethyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-6′-acetylamino-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid methyl ester,   (R)-4-(5-oxo-4,5-dihydro-[1,3,4]thiadiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(5-methyl-1H-pyrazol-3-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-isopropyl-benzylamide,   (R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-ethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-5′-amino-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4-methyl-5-pyrrolidin-1-ylmethyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-6,7-dihydro-4H-thiazolo[5,4-c]pyridine-5-carboxylic acid benzyl ester,   5-hydroxymethyl-2-[(R)-3-(4-isopropyl-benzylcarbamoyl)-4-(4-propyl-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   5-methoxymethyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   5-hydroxymethyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-4-carboxylic acid,   (R)-5′-dimethylaminomethyl-4-(4-ethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-5′-methanesulfonylamino-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-5′-hydroxymethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(6-hydroxy-pyridazin-3-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridazine-3-carboxylic acid amide,   (R)-4-(5-methyl-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-6′-amino-5′-hydroxymethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-propyl-benzylamide,   (R)-4-(2-oxo-1,4-dihydro-2H-pyrazino[2,3-d][1,3]oxazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-5′-pyrrolidin-1-ylmethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-3-carboxylic acid 4-tert-butyl-benzylamide,   (R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-5′-hydroxymethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-benzyl-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4,5-bis-hydroxymethyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(3-methyl-[1,2,4]thiadiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-ethyl-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-4-(5-hydroxymethyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(6-chloro-pyrimidin-4-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-pyrimidin-4-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4,6-dioxo-5,6-dihydro-4H-pyrrolo[3,4-d]thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-6′-amino-5′-hydroxymethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(3-methyl-[1,2,4]thiadiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-cyano-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(4-oxo-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(2-oxo-1,4-dihydro-2H-pyrazino[2,3-d][1,3]oxazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-pyrimidin-4-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(2-hydroxy-pyrimidin-4-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   4-amino-2-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid ethyl ester,   (R)-4-(2-amino-pyrimidin-4-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-amino-pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3,5′-dicarboxylic acid 5′-amide 3-[4-(1,1-difluoro-propyl)-benzylamide],   2-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-6,7-dihydro-4H-thiazolo[5,4-c]pyridine-5-carboxylic acid tert-butyl ester,   (R)-4-(4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(5-acetyl-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-5′-cyano-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-3-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-5′-morpholin-4-ylmethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-tert-butyl-benzylamide,   (R)-5′-(4-methyl-piperazin-1-ylmethyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-tert-butyl-benzylamide,   (R)-5′-dimethylaminomethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(3-acetylamino-[1,2,4]thiadiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-oxo-4,5-dihydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(5-methanesulfonyl-4,5,6,7-tetrahydro-thiazolo[5,4-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   2-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-6,7-dihydro-4H-thiazolo[5,4-c]pyridine-5-carboxylic acid ethylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   2-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-4-hydroxymethyl-thiazole-5-carboxylic acid,   (R)-6′-amino-5′-hydroxymethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(6-amino-pyrimidin-4-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(3-methoxy-[1,2,4]thiadiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(2-oxo-1,4-dihydro-2H-pyrazino[2,3-d][1,3]oxazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-(4-oxo-3,4-dihydro-thiazolo[4,5-d][1,2,3]triazin-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(ethyl-methyl-amino)-benzylamide,   5-[(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridine-2-carboxylic acid,   (R)-4-(3-methoxy-[1,2,4]thiadiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[1,2,4]triazolo[1,5-a]pyrimidin-5-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(2-oxo-2,3-dihydro-1H-imidazo[4,5-b]pyrazin-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-chloro-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (6-dimethylamino-pyridin-3-ylmethyl)-amide,   5-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyridine-2-carboxylic acid,   (R)-4-quinoxalin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-6′-amino-5′-aminomethyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (benzoxazol-2-ylmethyl)-amide,   (R)-4-(4-oxo-3,4-dihydro-thiazolo[4,5-d][1,2,3]triazin-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(6-hydroxy-[1,2,5]thiadiazolo[3,4-b]pyrazin-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(2,2-dioxo-1,2,3,4-tetrahydro-2λ 6 -pyrazino[2,3-c][1,2,6] thiadiazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-ethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-thiophen-2-yl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-bromo-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-cyclopropyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-methoxymethyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-methoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid ([2,2′]bithiophenyl-5-ylmethyl)-amide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-methylsulfanyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (1-propyl-1,2,3,6-tetrahydro-pyridin-4-ylmethyl)-amide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (biphenyl-4-ylmethyl)-amide,   (R)-4-(4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(1H-imidazo[4,5-b]pyrazin-5-yl)-1-(4-tri fluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (2-oxo-1-propyl-1,2-dihydro-pyridin-4-ylmethyl)-amide,   (R)-1-(4-bromo-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(6-bromo-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(7-bromo-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-bromo-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-5′-carboxylic acid,   (R)-4-(6-chloro-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-tert-butyl-benzylamide,   (R)-4-pyrazino[2,3-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[1,2,5]thiadiazolo[3,4-b]pyrazin-5-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(2-methyl-pteridin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-quinoxaline-6-carboxylic acid ethyl ester,   (R)-4-thiazolo[4,5-d]pyridazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-tert-butyl-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(biphenyl-4-sulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-chloro-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-nitro-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-tert-butyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-5′-carboxylic acid,   (R)-4-(biphenyl-4-sulfonyl)-3-(4-propyl-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2]bipyrazinyl-5′-carboxylic acid,   (R)-4-(4-oxo-4,5-dihydro-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-iodo-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-thiophen-2-yl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   3-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-quinoxaline-6-carboxylic acid ethyl ester,   3-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-quinoxaline-6-carboxylic acid,   2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-quinoxaline-6-carboxylic acid,   (R)-1-(4-chloro-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-tert-butyl-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-thiazolo[5,4-c]pyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (6-propyl-pyridin-3-ylmethyl)-amide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (5-methyl-pyrazin-2-ylmethyl)-amide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 3-amino-4-propyl-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 3-hydroxy-4-propyl-benzylamide,   (R)-1-(2′-hydroxy-biphenyl-4-sulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(3′-hydroxy-biphenyl-4-sulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-nitro-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(biphenyl-4-sulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   5-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiophene-2-carboxylic acid tert-butyl ester,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (5-pyridin-2-yl-thiophen-2-ylmethyl)-amide,   (4′-{(R)-2-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-pteridin-7-yl-piperazine-1-sulfonyl}-biphenyl-2-yloxy)-acetic acid,   (4′-{(R)-2-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-pteridin-7-yl-piperazine-1-sulfonyl}-biphenyl-3-yloxy)-acetic acid,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-dimethylamino-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-thiazolo[5,4-b]pyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-[1,6]naphthyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-chloro-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(8-chloro-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-pyrolidin-1-yl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   trans-[4-(4-{(R)-2-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-pteridin-7-yl-piperazine-1-sulfonyl}-phenyl)-cyclohexyl]-acetic acid,   (R)-4-pyrido[3,4-b]pyrazin-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-morpholin-4-yl-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-methoxy-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrazino[2,3-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,2,4]triazolo[1,5-a]pyrimidin-5-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-[4-(2-oxo-pyrrolidin-1-yl)-benzenesulfonyl]-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-(4-chloro-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   4′-{(R)-2-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-pteridin-7-yl-piperazine-1-sulfonyl}-biphenyl-3-carboxylic acid,   (R)-1-(4-nitro-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-pyrrolidin-1-yl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(3H-imidazo[4,5-c]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[3,4-b]pyrazin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(1H-benzimidazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-1-[4-(5-oxo-2,5-dihydro-[1,2,4]oxadiazol-3-yl)-benzenesulfonyl]-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-3-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(2,2,2-trifluoro-ethoxy)-benzylamide,   (methyl-{4-[(R)-4-pyrido[3,4-b]pyrazin-2-yl-2-(4-trifluoromethoxy-benzylcarbamoyl)-piperazine-1-sulfonyl]-phenyl}-amino)-acetic acid ethyl ester,   (methyl-[4-[(R)-4-pyrido[3,4-b]pyrazin-2-yl-2-(4-trifluoromethoxy-benzylcarbamoyl)-piperazine-1-sulfonyl]-phenyl]-amino)-acetic acid,   (R)-4-(5-chloro-quinoxalin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(2-methyl-pteridin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[5,4-c]pyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pyrido[2,3-b]pyrazin-3-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,6]naphthyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethylsulfanyl-benzylamide,   4-{5-[(R)-2-(4-propyl-benzylcarbamoyl)-4-pteridin-7-yl-piperazine-1-sulfonyl]-2-trifluoromethoxy-phenyl}-butyric acid,   6-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-nicotinic acid,   (R)-4-thiazolo[5,4-b]pyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-iodo-benzenesulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-1-(3′-hydroxy-biphenyl-4-sulfonyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-2-carboxylic acid 4-propyl-benzylamide,   {4′-[(R)-2-(4-propyl-benzylcarbamoyl)-4-pyrido[3,4-b]pyrazin-2-yl-piperazine-1-sulfonyl]-biphenyl-3-yloxy}-acetic acid,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-quinoxaline-5-carboxylic acid,   3-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-quinoxaline-5-carboxylic acid,   (R)-4-quinoxalin-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-oxo-3,4-dihydro-thiazolo[4,5-d][1,2,3]triazin-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-ethyl-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-4-(4-pyrrolidin-1-yl-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-1-(4-nitro-benzenesulfonyl)-4-pteridin-7-yl-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,5]naphthyridin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-b]pyrazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 2,3,5,6-tetrafluoro-4-trifluoromethyl-benzylamide,   (R)-4-(4-ethyl-benzenesulfonyl)-5′-hydroxymethyl-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 2,4,6-trichloro-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(2-trifluoromethyl-pteridin-7-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(8-bromo-pyrido[3,4-b]pyrazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5,7-dichloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4,7-dioxo-4,5,6,7-tetrahydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (adamantan-1-ylmethyl)-amide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid amide,   3-{2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazin-8-yl}-propionic acid,   (R)-6′-methyl-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   (R)-4-[8-(2-carbamoyl-ethyl)-pyrido[3,4-b]pyrazin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (3-phenyl-propyl)-amide,   (R)-1-(4-ethyl-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(8-bromo-pyrido[3,4-b]pyrazin-2-yl)-1-(4-ethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-quinoxaline-5-carboxylic acid,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   3-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-quinoxaline-5-carboxylic acid,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-quinoxaline-5-carboxylic acid,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-benzothiazole-4-carboxylic acid,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   2-methyl-6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-nicotinic acid,   5-fluoro-2-methyl-6-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-nicotinic acid,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   (R)-1-(4-nitro-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   3-{4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-5-yl}-propionic acid,   (R)-4-(4-methyl-5-sulfamoyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(4-methyl-5-methylsulfamoyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(5-dimethylsulfamoyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-(5-acetylsulfamoyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-1-(4-nitro-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-3-[4-(1,1-difluoro-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   (R)-4-(4-methyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-dimethyl-propyl)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-butyl-benzylamide,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   2-[(R)-4-(4-nitro-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   2-[(R)-4-(4-tert-butyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   2-[(R)-4-(4-chloro-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   {4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-5-yl}-oxo-acetic acid ethyl ester,   4-chloro-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   {4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-5-yl}-oxo-acetic acid,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (2-phenyl-cyclopropylmethyl)-amide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(2-methoxy-1,1-dimethyl-ethyl)-benzylamide,   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3,5′-dicarboxylic acid 5′-ethylamide 3-(4-trifluoromethoxy-benzylamide),   (R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-3,5′-dicarboxylic acid 5′-tert-butylamide 3-(4-trifluoromethoxy-benzylamide),   2-[(R)-3-[4-(1,1-dimethyl-propyl)-benzylcarbamoyl]-4-(4-ethyl-benzenesulfonyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   2-[(R)-3-(4-butyl-benzylcarbamoyl)-4-(4-ethyl-benzenesulfonyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid,   hydroxy-{4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-5-yl}-acetic acid ethyl ester,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (5-propyl-thiophen-2-ylmethyl)-amide,   (R)-4-(4-methyl-5-methylaminooxalyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazine-4-carboxylic acid ethyl ester,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazine-4-carboxylic acid,   (R)-1-(4-fluoro-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid methylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid dimethylamide,   (R)-4-pteridin-7-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (1-phenyl-azetidin-3-ylmethyl)-amide,   4-chloro-2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   (R)-4-(7-chloro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-hydroxymethyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-pyrido[3,4-b]pyrazine-8-carboxylic acid isopropylamide,   (R)-4-(8-cyano-pyrido[3,4-b]pyrazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-chloro-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   7-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-6,7-dihydro-thiazolo[4,5-d]pyridazine-4-carboxylic acid,   7-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-6,7-dihydro-thiazolo[4,5-d]pyridazine-4-carboxylic acid methylamide,   7-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-6,7-dihydro-thiazolo[4,5-d]pyridazine-4-carboxylic acid amide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-hydroxy-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyridazin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   7-chloro-2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid ethyl ester,   (R)-1-(4-bromo-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1-methoxymethyl-cyclopropyl)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(ethyl-methyl-amino)-benzylamide,   (R)-1-(4-methoxy-benzenesulfonyl)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[5,4-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5,7-dihydroxy-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   4-chloro-2-[(R)-3-[4-(1,1-dimethyl-propyl)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid ethyl ester,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid,   (R)-4-(4-methyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(7-chloro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyridazin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1,2,2-tetrafluoro-ethoxy)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (3-phenyl-cyclobutylmethyl)-amide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (naphthalen-2-ylmethyl)-amide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(6-methyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methoxy-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-chloro-4-methyl-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-chloro-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (4-methyl-2-propyl-thiazol-5-ylmethyl)-amide,   (R)-4-(5-methyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-bromo-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-propyl-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid amide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid methylamide,   (R)-4-(4-methyl-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-difluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-thiazolo[4,5-d]pyrimidin-2-yl-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-methyl-5-oxo-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[5,4-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(6-oxo-piperidin-3-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(6-oxo-1,6-dihydro-pyridin-3-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide hydrochloride,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(7-chloro-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-chloro-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-methoxy-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyridazine-4-carboxylic acid dimethylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(3-methyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-chloro-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(1,1-difluoro-propyl)-benzylamide,   (R)-4-(4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(difluoro-methoxy-methyl)-benzylamide,   (R)-4-(7-oxo-6,7-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-methoxymethyl-benzylamide,   (R)-4-(4-hydroxymethyl-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-chloro-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-amino-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-methoxy-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-dimethylamino-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(2-hydroxy-ethylamino)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   7-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-5-carboxylic acid methyl ester,   (R)-4-(5-ethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-ethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(3-trifluoromethyl-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methylamino-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazol-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-difluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-thiazolo[4,5-d]pyrimidin-2-yl-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-methyl-4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-(ethyl-methyl-amino)-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-4-thiazolo[4,5-d]pyrimidin-2-yl-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-amino-5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyano-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-methoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-fluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-fluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-cyclopropyl-benzylamide,   (R)-4-(5-fluoro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benz enesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-isopropylamino-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-bromo-7-diethylamino-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-cyclopropyl-benzylamide,   (R)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-acetyl-4-methyl-thiazol-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid amide,   (R)-4-(1,3-dimethyl-1H-pyrazolo[3,4-d]thiazol-5-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethyl-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-amino-5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-isopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-chloro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(3-methyl-4-oxo-4H-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d][1,2,3]triazin-6-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid (indolizin-2-ylmethyl)-amide,   7-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidine-5-carboxylic acid methylamide,   (R)-4-(5-isopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropylmethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-chloro-2-diethylamino-thiazolo[4,5-d]pyrimidin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(3-hydroxy-3-methyl-but-1-ynyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-ethynyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-pentafluorosulfanyl-benzylamide,   (R)-4-(5-chloro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   (R)-4-thiazolo[4,5-d]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethyl-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-[4-(2-hydroxy-ethylamino)-thiazolo[4,5-d][1,2,3]triazin-6-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-5-trifluoromethyl-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-thiazolo[4,5-d][1,2,3]triazin-6-yl-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid ethyl ester,   (R)-4-(5-hydroxymethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-methoxy-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyano-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyano-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-cyclopropylmethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-3-(4-trifluoromethoxy-benzylcarbamoyl)-4-(4-trifluoromethyl-benzenesulfonyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid amide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-difluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-difluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-methyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-amino-5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-methoxy-5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-tert-butyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-tert-butyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxyli c acid 4-trifluoromethoxy-benzylamide,   (R)-4-(6-chloro-5-methyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-methyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   5-methyl-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-7-carboxylic acid amide,   (R)-4-(5-methyl-4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-oxo-3-trifluoromethyl-4H-[1,3,4]thiadiazolo[2,3-c][1,2,4]triazin-7-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid,   (R)-4-(4-amino-thiazolo[4,5-d][1,2,3]triazin-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(4-methoxy-thiazolo[4,5-d][1,2,3]triazin-6-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyano-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-ethyl-4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-oxo-7-trifluoromethyl-5H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid dimethylamide,   (R)-1-(4-trifluoromethyl-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   (R)-4-(5-methoxymethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-2-fluoro-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid methylamide,   (R)-4-[5-(1-hydroxy-1-methyl-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-acetyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-5-trifluoromethyl-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methoxy-thiazolo[5,4-b]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-methyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-[4-(1,1,2,2-tetrafluoro-ethoxy)-benzenesulfonyl]-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-hydroxymethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[4,5-d]pyrimidine-5-carboxylic acid methoxy-methyl-amide,   (R)-4-(7-amino-5-methoxymethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-pyrrolidin-1-ylmethyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(1-hydroxy-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-trifluoromethoxy-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide,   (R)-4-(5-oxo-4,5-dihydro-thiazolo[5,4-b]pyridin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-difluoromethoxy-benzenesulfonyl)-4-(7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid ethyl ester,   2-[(R)-4-(4-ethyl-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid,   (R)-4-(7-oxo-5-trifluoromethyl-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(7-oxo-5-trifluoromethyl-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(7-oxo-5-trifluoromethyl-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(5-cyclobutyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(2-methoxy-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(2-methoxy-ethyl)-4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclobutyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide,   (R)-4-[5-(1-hydroxy-1-methyl-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(1-methoxymethyl-cyclopropyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(1-hydroxymethyl-cyclopropyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(2-hydroxy-ethyl)-4-oxo-4,5-dihydro-thiazolo[4,5-d]pyridazin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(1-methoxy-cyclopropyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[5-(1-hydroxy-cyclopropyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-6-carboxylic acid tert-butyl ester,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-6-carboxylic acid,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid ethyl ester,   2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid,   (R)-1-(4-trifluoromethyl-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide,   (R)-4-(5-oxo-4,5-dihydro-thiazolo[5,4-b]pyridin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-difluoromethoxy-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-isopropyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-isopropyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-benzylamide,   (R)-4-(7-amino-5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-[7-amino-5-(1-hydroxy-1-methyl-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   hydroxy-{4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazol-5-yl}-acetic acid,   4-chloro-2-[(R)-3-[4-(ethyl-methyl-amino)-benzylcarbamoyl]-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazole-5-carboxylic acid,   {5-methyl-3-[(R)-3-(4-propyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-pyrazol-1-yl}-acetic acid,   [(R)-3-(4-tert-butyl-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-ylmethyl]-triethyl-ammonium trifluoro-methanesulfonate,   (R)-4-[5-(2-hydroxy-ethyl)-thiazolo[4,5-d]pyrimidin-2-yl]-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-cyclopropyl-benzenesulfonyl)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-1-(4-cyclopropyl-benzenesulfonyl)-4-(5-trifluoromethyl-thiazolo[4,5-d]pyrimidin-2-yl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 3-fluoro-4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 3-fluoro-4-trifluoromethoxy-benzylamide,   2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid,   (R)-4-(5-hydroxymethyl-7-oxo-7H-[1,3,4]thiadiazolo[3,2-a]pyrimidin-2-yl-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   {4-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-4H-thiazolo[4,5-d]pyridazin-5-yl}-acetic acid,   (R)-4-(5-cyclopropyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-4-(5-cyclopropyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   2-[(R)-3-(4-difluoromethoxy-3-fluoro-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazin-1-yl]-thiazolo[5,4-c]pyridine-7-carboxylic acid,   (R)-4-(5-cyclopropyl-thiazolo[4,5-d]pyrimidin-2-yl)-1-(2-fluoro-4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-trifluoromethoxy-benzylamide,   (R)-3-(4-difluoromethoxy-3-fluoro-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-3,4,5,6-tetrahydro-2H-[1,2′]bipyrazinyl-5′-carboxylic acid,   3-{4-oxo-2-[(R)-4-(4-trifluoromethoxy-benzenesulfonyl)-3-(4-trifluoromethoxy-benzylcarbamoyl)-piperazin-1-yl]-4H-thiazolo[4,5-d]pyridazin-5-yl}propionic acid,   (R)-4-(5-cyclopropyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide, and   (R)-4-(5-cyclopropyl-7-oxo-6,7-dihydro-thiazolo[4,5-d]pyrimidin-2-yl)-1-(4-trifluoromethyl-benzenesulfonyl)-piperazine-2-carboxylic acid 4-difluoromethoxy-3-fluoro-benzylamide,   or a pharmaceutically acceptable salt thereof, or a solvate thereof.   
     
     
         33 . A pharmaceutical composition comprising a compound of any one of  claims 15  to  18  or a pharmaceutically acceptable salt thereof, or a solvate thereof, and a pharmaceutically acceptable carrier. 
     
     
         34 .- 43 . (canceled) 
     
     
         44 . A method for treating hepatitis C in a mammal, which method comprises administering an effective amount of a compound represented by the formula [I], or a pharmaceutically acceptable salt thereof, or a solvate thereof to a mammal with hepatitis C, thereby treating hepatitis C in the mammal: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         R is 
         a hydrogen atom, 
         —COR 1 , 
         —COOR 2 , 
         —CONR 3 R 4 , 
         —SO 2 R 5 , 
         —CO—COOR 6 , 
         —CO—CH═CH—COOR 11 , 
         —CO—(CH 2 ) a —NH—R 7 , 
         —CO—(CH 2 ) b —NHCOR 8 , 
         —CO—(CH 2 ) c —NHCOOR 9    
         (wherein R 1  to R 9  and R 11  are the same or different and each is 
         a hydrogen atom or a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, and 
         a, b and c are the same or different and each is an integer of 1 to 4), 
         —CO—CONH 2 , 
         —C(═NH)NH 2 , 
         —C(═S)NH 2 , 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, or 
       
       
         
           
           
               
               
           
         
         wherein X is 
         a bond, 
         C 1-4  alkylene, 
         —CO—(CH 2 ) p —, 
         —CONR 10 —(CH 2 ) q —, 
         —CO—(CH 2 ) r —O—(CH 2 ) s —, 
         —CO—(CH 2 ) t —NH—(CH 2 ) u —, 
         —CO—(CH 2 ) v —CONH—(CH 2 ) w —, or 
         —CO—NH—SO 2 —, 
         ring C is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         R 10  is a hydrogen atom, or a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         p, q, r, s, u, v and w are the same or different and each is 0 or an integer of 1 to 4, and t is an integer of 1 to 4, 
         group A: 
         halogen atom, nitro group, cyano group, 
         OR a1    
         —SR a2 , 
         —NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  Carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogeno C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         45 . The method of  claim 44  further comprising administering an effective amount of at least one pharmaceutical agent selected from the group consisting of a different antiviral agent, an antiinflammatory agent and an immunostimulant to the mammal. 
     
     
         46 . The method of  claim 44  further comprising administering an effective amount of interferon to the mammal. 
     
     
         47 . A method for inhibiting HCV polymerase in a mammal, which comprises administering an effective amount of a compound represented by the formula [I], or a pharmaceutically acceptable salt thereof, or a solvate thereof to a mammal, thereby inhibiting HCV polymerase in the mammal: 
       
         
           
           
               
               
           
         
         wherein 
         ring A is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         n is an integer of 1 to 6, 
         ring B is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         R is 
         a hydrogen atom, 
         —COR 1 , 
         —COOR 2 , 
         —CONR 3 R 4 , 
         —SO 2 R 5 , 
         —CO—COOR 6 , 
         —CO—CH═CH—COOR 11 , 
         —CO—(CH 2 ) a —NH—R 7 , 
         —CO—(CH 2 ) b —NHCOR 8 , 
         —CO—(CH 2 ) c —NHCOOR 9    
         (wherein R 1  to R 9  and R 11  are the same or different and each is 
         a hydrogen atom or a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, and 
         a, b and c are the same or different and each is an integer of 1 to 4), 
         —CO—CONH 2 , 
         —C(═NH)NH 2 , 
         —C(═S)NH 2 , 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, or 
       
       
         
           
           
               
               
           
         
         wherein X is 
         a bond, 
         C 1-4  alkylene, 
         —CO—(CH 2 ) p —, 
         —CONR 10 —(CH 2 ) q —, 
         —CO—(CH 2 ) r —O—(CH 2 ) s —, 
         —CO—(CH 2 ) t —NH—(CH 2 ) u —, 
         —CO—(CH 2 ) v —CONH—(CH 2 ) w —, or 
         —CO—NH—SO 2 —, 
         ring C is 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group A, or 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group A 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         R 10  is a hydrogen atom, or a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         p, q, r, s, u, v and w are the same or different and each is 0 or an integer of 1 to 4, and t is an integer of 1 to 4, 
         group A: 
         halogen atom, nitro group, cyano group, 
         —OR a1 , 
         —SR a2 , 
         NR a3 R a4 , 
         —NHCOR a5 , 
         —NHSO 2 R a14 , 
         —COOR a6 , 
         —CONR a7 R a8 , 
         —SO 2 NR a9 R a10 , 
         —SO 2 NHCOR a15 , 
         —COR a11 , 
         —SO 2 R a12 , 
         —CONHSO 2 R a13 , 
         —COCOOR a16 , 
         —COCONR a17 R a18 , 
         —CONR a19 (OR a20 ), 
         —SF 5    
         (wherein R a1  to R a20  are the same or different and each is 
         a hydrogen atom, 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), or 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C), 
         a C 1-10  alkyl group optionally substituted by 1 to 5 substituents selected from the following group B, 
         a C 2-10  alkynyl group optionally substituted by 1 to 5 substituents selected from the following group B 
         a C 3-12  carbon ring group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclic group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclic group has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         a C 6-12  aryl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         a heterocyclyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), and 
         a C 3-10  cycloalkyl-C 1-4  alkyl group optionally substituted by 1 to 5 substituents selected from the following group C, 
         group B: 
         halogen atom, cyano group, hydroxyl group, 
         C 1-4  alkoxy group, 
         amino group, 
         C 1-4  alkylamino group, 
         di(C 1-4  alkyl)amino group, 
         carboxyl group, 
         C 1-4  alkoxy-carbonyl group, 
         carbamoyl group, 
         C 1-4  alkylamino-carbonyl group, 
         di(C 1-4  alkyl)amino-carbonyl group, 
         heterocyclyl-carbonyl group, and 
         tri(C 1-4  alkyl)ammoniumyl group 
         (wherein the heterocyclyl moiety has, besides carbon atom, 1 to 6 hetero atoms selected from nitrogen atom, oxygen atom and sulfur atom), 
         group C: 
         halogen atom, cyano group, hydroxyl group, 
         carboxyl group, 
         C 1-4  alkyl group, 
         halogeno C 1-4  alkyl group, 
         hydroxy C 1-4  alkyl group, 
         carboxy C 1-4  alkyl group, 
         C 1-4  alkoxy C 1-4  alkyl group, 
         C 1-4  alkoxy group, and 
         carboxy C 1-4  alkoxy group. 
       
     
     
         48 . The method of  claim 47  further comprising administering an effective amount of at least one pharmaceutical agent selected from the group consisting of a different antiviral agent, an antiinflammatory agent and an immunostimulant to the mammal. 
     
     
         49 . The method of  claim 47  further comprising administering an effective amount of interferon to the mammal. 
     
     
         50 . (canceled) 
     
     
         51 . (canceled)