Luminogenic and fluorogenic compounds and methods to detect molecules or conditions

Abstract

A method to detect the presence or amount of at least one molecule in a sample which employs a derivative of luciferin or a derivative of a fluorophore is provided. Compounds and compositions for carrying out the methods of the invention are also provided.

What is claimed is: 
     
         1 . A compound of formula (X) or a salt thereof: 
       
         
           
           
               
               
           
         
       
       wherein
 R 1  is H, C 1-6 alkyl, phenylC 1-6 alkyl, or hydroxyC 1-6 alkyl; 
 R 2  is C 1-6 alkyl, phenylC 1-6 alkyl, or hydroxyC 1-6 alkyl; 
 wherein any alkyl or phenyl group of R 1  and R 2  can optionally be substituted with one or two amino groups; and 
 wherein any amino group substituent of R 1  and R 2  can be substituted with one or two optionally substituted C 1-6 alkyl, C 1-6 alkylcarbonyl, or C 1-6 alkoxycarbonyl groups. 
 
     
     
         2 . The compound or salt thereof of  claim 1 , wherein the —CO 2 H substituent on the thiazole ring of formula (X) is in the (S) stereochemical configuration. 
     
     
         3 . The compound or salt thereof of  claim 2 , wherein R 1  is H and R 2  is unsubstituted phenylC 1-6 alkyl. 
     
     
         4 . The compound or salt thereof of  claim 2 , wherein R 1  is H and R 2  is phenylC 1-6 alkyl, and phenyl is substituted with amino, optionally substituted C 1-6 alkylamino, or optionally substituted di-C 1-6 alkylamino. 
     
     
         5 . The compound or salt thereof of  claim 2 , wherein R 1  is H and R 2  is phenylC 1-6 alkyl, wherein phenyl is substituted with amino, and the amino group is substituted with optionally substituted C 1-6 alkylcarbonyl or C 1-6 alkoxycarbonyl. 
     
     
         6 . A luciferase substrate comprising a compound of  claim 2 . 
     
     
         7 . The compound of  claim 1 , wherein R 1  is H and R 2  is methyl, ethyl, propyl, butyl, pentyl, or hexyl. 
     
     
         8 . The compound of  claim 1 , wherein R 1  is methyl, ethyl, propyl, butyl, pentyl, or hexyl, and R 2  is methyl, ethyl, propyl, butyl, pentyl, or hexyl. 
     
     
         9 . The compound of  claim 1 , wherein R 1  is H and R 2  is benzyl, phenethyl, phenylpropyl, phenylbutyl, phenylpentyl, or phenylhexyl. 
     
     
         10 . The compound of  claim 1 , wherein R 1  is H and R 2  is benzyl, phenethyl, phenylpropyl, phenylbutyl, phenylpentyl, or phenylhexyl wherein the benzene ring of R 2  is substituted with an amino group. 
     
     
         11 . The compound of  claim 1  having any one of the following structures: 
       
         
           
           
               
               
           
         
       
     
     
         12 . A compound represented by the following general formula (I) or a salt thereof: 
       
         
           
           
               
               
           
         
       
       wherein
 R 1  and R 2  independently represent hydrogen, a C 1-6 alkyl group which may be substituted, or a group represented by formula (A): 
 
       
         
           
           
               
               
           
         
       
       wherein X 1  and X 2  independently represent hydrogen or —N(R 3 )(R 4 ), wherein R 3  and R 4  independently represent hydrogen a C 1-6  alkyl group which may be substituted, a C 1-6  alkylcarbonyl group which may be substituted, or a C 1-6  alkoxycarbonyl group which may be substituted; and
 n represents an integer of 1 to 6; 
 provided that R 1  and R 2  do not simultaneously represent hydrogen. 
 
     
     
         13 . The compound or a salt thereof according to  claim 12 , wherein either one of R 1  and R 2  is hydrogen, and the other is a group represented by the formula (A), and in the formula (A), X 1  and X 2  both are hydrogen atoms, and n is an integer of 1 to 6. 
     
     
         14 . The compound or a salt thereof according to  claim 12 , wherein either one of R 1  and R 2  is hydrogen, and the other is a group represented by the formula (A), and in the formula (A), X 1  is hydrogen, and X 2  is a group represented as —N(R 3 )(R 4 ), wherein R 3  and R 4  independently represent hydrogen, or a C 1-6  alkyl group which may be substituted. 
     
     
         15 . The compound or a salt thereof according to  claim 12 , wherein either one of R 1  and R 2  is hydrogen, and the other is a group represented by the formula (A), and in the formula (A), X 1  is hydrogen, and X 2  is a group represented as —N(R 3 )(R 4 ), wherein either one of R 3  and R 4  is hydrogen, and the other is a C 1-6 alkylcarbonyl group which may be substituted, or a C 1-6 alkyloxycarbonyl group which may be substituted. 
     
     
         16 . A composition comprising a luciferase substrate and an aqueous carrier, wherein the luciferase substrate is a compound of  claim 12 .