Novel coumarin derivatives

Abstract

A compound represented by the following general formula (I) or a salt thereof [R 1 represents hydrogen atom, or a C 1-12 alkyl group; R 2 represents a C 1-12 alkyl group having one or more maleimide groups, an aryl group having two or more maleimide groups, a group represented by the formula (A): —(CH 2 ) n —CO—N(R 11 )(R 12 ) (R 11 and R 12 represent hydrogen atom, a C 1-12 alkyl group, a C 1-12 alkyl group having one or more maleimide groups, or an aryl group having one or more maleimide groups, and n represents an integer of 1 to 6), or a group represented by the formula (B): —(CH 2 ) m —NH—CO—R 13 (R 13 represents a C 1-12 alkyl group having one or more maleimide groups, or an aryl group having one or more maleimide groups, and m represents an integer of 1 to 6); R 3 and R 5 represent hydrogen atom, or a halogen atom; R 4 represents hydroxyl group, a C 1-12 acyloxy group, a C 1-12 acyloxymethyloxy group, or an amino group], which is useful as a novel fluorescent labeling agent having a property of emitting intense fluorescence only after reacting with a thiol group.

1 - 10 . (canceled) 
   
   
       11 . A compound represented by formula (V), or a salt thereof: 
     
       
         
         
             
             
         
       
     
   
   
       12 . A method for fluorescent labeling a compound having a thiol group, or a peptide, or a protein containing a cysteine residue comprising the compound or a salt thereof according to  claim 11 . 
   
   
       13 . A fluorescent labeling agent for fluorescent labeling of a compound having a thiol group, or a peptide or protein containing a cysteine residue, which contains the compound or a salt thereof according to  claim 11 . 
   
   
       14 . A fluorescent labeling agent for fluorescent labeling of a compound having two or more cysteine residues, which contains the compound or a salt thereof according to  claim 11 . 
   
   
       15 . A compound represented by formula (VI), or a salt thereof: 
     
       
         
         
             
             
         
       
     
   
   
       16 . A method for fluorescent labeling a compound having a thiol group, or a peptide, or a protein containing a cysteine residue comprising the compound or a salt thereof according to  claim 15 . 
   
   
       17 . A fluorescent labeling agent for fluorescent labeling of a compound having a thiol group, or a peptide or protein containing a cysteine residue, which contains the compound or a salt thereof according to  claim 15 . 
   
   
       18 . A fluorescent labeling agent for fluorescent labeling of a compound having two or more cysteine residues, which contains the compound or a salt thereof according to  claim 15 . 
   
   
       19 . A compound represented by formula (VII), or a salt thereof: 
     
       
         
         
             
             
         
       
     
   
   
       20 . A method for fluorescent labeling a compound having a thiol group, or a peptide, or a protein containing a cysteine residue comprising the compound or a salt thereof according to  claim 19 . 
   
   
       21 . A fluorescent labeling agent for fluorescent labeling of a compound having a thiol group, or a peptide or protein containing a cysteine residue, which contains the compound or a salt thereof according to  claim 19 . 
   
   
       22 . A fluorescent labeling agent for fluorescent labeling of a compound having two or more cysteine residues, which contains the compound or a salt thereof according to  claim 19 . 
   
   
       23 . A compound represented by formula (VIII), or a salt thereof: 
     
       
         
         
             
             
         
       
     
   
   
       24 . A method for fluorescent labeling a compound having a thiol group, or a peptide, or a protein containing a cysteine residue comprising the compound or a salt thereof according to  claim 23 . 
   
   
       25 . A fluorescent labeling agent for fluorescent labeling of a compound having a thiol group, or a peptide or protein containing a cysteine residue, which contains the compound or a salt thereof according to  claim 23 . 
   
   
       26 . A fluorescent labeling agent for fluorescent labeling of a compound having two or more cysteine residues, which contains the compound or a salt thereof according to  claim 23 . 
   
   
       27 . A compound represented by formula (IX), or a salt thereof: 
     
       
         
         
             
             
         
       
     
   
   
       28 . A method for fluorescent labeling a compound having a thiol group, or a peptide, or a protein containing a cysteine residue comprising the compound or a salt thereof according to  claim 27 . 
   
   
       29 . A fluorescent labeling agent for fluorescent labeling of a compound having a thiol group, or a peptide or protein containing a cysteine residue, which contains the compound or a salt thereof according to  claim 27 . 
   
   
       30 . A fluorescent labeling agent for fluorescent labeling of a compound having two or more cysteine residues, which contains the compound or a salt thereof according to  claim 27 .