Process for preparing mannose derivatives

Abstract

The invention relates to a process to prepare a compound of the following formula (I):in whichP represents a protective group of a hydroxyl function which is a —COR1 group with R1 representing an aryl or a (C1-C6)alkyl,R represents a hydrogen atom or a protective group of a terminal alkyne, from mannose, comprising the following steps:(a) protecting the 5 hydroxyl groups of the mannose by a protective group P;(b) coupling the protected mannose obtained at step (a) with a compound of the following formula (II)The present invention also relates to a compound of formula (IIIa):wherein R10 represents a hydrogen, a (C1-C6)alkyl, —SO2R6, —C(O)R6 or —C(O)OR6, with R6 being a hydrogen or a radical selected from a (C1-C6)alkyl, an aryl, a heteroaryl, a 3-8 membered ring cycloalkyl and a 3-8 membered ring heterocycloalkyl, said radical being optionally substituted by a (C1-C6) alkyl, an aryl, a heteroaryl, a 3-8 membered ring cycloalkyl or a 3-8 membered ring heterocycloalkyl, a halogen, —NR8R9, —CN, —C(O)OR8, —C(O)NR8R9 or —OR8, with R8 and R9 being independently a hydrogen atom or a (C1-C6) alkyl, or R8 and R9 form together with the nitrogen to which they are bound a 3-8 membered ring heterocycloalkyl, andR″ represents —COR1 group with R1 being an aryl or a (C1-C6)alkyl.

1 . A compound of formula (IIIa): 
       
         
           
           
               
               
           
         
         wherein R 10  represents a hydrogen, a (C 1 -C 6 )alkyl, —SO 2 R 6 , —C(O)R 6  or —C(O)OR 6 , with R 6  being a hydrogen or a radical selected from a (C 1 -C 6 )alkyl, an aryl, a heteroaryl, a 3-8 membered ring cycloalkyl and a 3-8 membered ring heterocycloalkyl, said radical being optionally substituted by a (C 1 -C 6 ) alkyl, an aryl, a heteroaryl, a 3-8 membered ring cycloalkyl or a 3-8 membered ring heterocycloalkyl, a halogen, —NR 8 R 9 , —CN, —C(O)OR 8 , —C(O)NR 8 R 9  or —OR 8 , with R 8  and R 9  being independently a hydrogen atom or a (C 1 -C 6 ) alkyl, or R 8  and R 9  form together with the nitrogen to which they are bound a 3-8 membered ring heterocycloalkyl and R″ represents —COR 1  group with R 1  being an aryl. 
       
     
     
         2 . The compound of  claim 1 , wherein R 10  represents a hydrogen, a (C 1 -C 6 )alkyl, —SO 2 R 6 , —C(O)R 6  or —C(O)OR 6 . 
     
     
         3 . The compound of  claim 2 , wherein R 10  represents —C(O)R 6 . 
     
     
         4 . The compound of  claim 3 , wherein R 6  is an aryl. 
     
     
         5 . The compound of  claim 3 , wherein R 6  is a (C 1 -C 6 )alkyl. 
     
     
         6 . The compound of  claim 5 , wherein R 6  is a methyl group. 
     
     
         7 . The compound of  claim 1 , wherein R 1  is a phenyl. 
     
     
         8 . The compound of  claim 1 , being of formula (IIIa)-2: