Process and method for the preparation of asymetric monfunctionalised indocyanine labelling reagents and obtained compounds

Abstract

A process for preparing an asymmetrical indocyanine dye comprising the steps of: a) reacting a first quaternised indolenine or substituted indolenine with a compound of the formula (II) or hydrochloride thereof, wherein n is 0 or 1 Ph is phenyl or substituted phenyl X is hydrogen, halogen or alkyl, preferably chlorine, in a solvent selected from the group consisting of acetic acid, acetic anhydride and mixtures thereof in the presence of acetyl chloride, to obtain an intermediate hemicyanine, and b) further reacting said intermediate hemicyanine with a second quaternised indolenine or substituted indolenine different from said first indolenine.

1 . A process for preparing an asymmetrical indocyanine dye comprising the steps of: 
 a) reacting a first quaternised indolenine or substituted indolenine with a compound of the formula (II)                          or hydrochloride thereof,    wherein n is 0 or 1    Ph is phenyl or substituted phenyl    X is hydrogen, halogen or alkyl, preferably chlorine, in a solvent selected from the group consisting of acetic acid, acetic anhydride and mixtures thereof in the presence of acetyl chloride, to obtain an intermediate hemicyanine, and    b) further reacting said intermediate hemicyanine with a second quaternised indolenine or substituted indolenine different from said first indolenine.    
   
   
       2 . A process according to  claim 1  wherein the amount of acetyl chloride is from 0.5 to 50% v/v, preferably from 1% to 20% v/v referred to the acetic acid/acetic anhydride solvent.  
   
   
       3 . A process according to  claim 1  wherein said first indolenine is less reactive than said second indolenine.  
   
   
       4 . A process according to  claim 3 , wherein said first indolenine bears electron withdrawing groups in the benzene ring.  
   
   
       5 . A process according to  claim 3 , wherein said first indolenine has additional condensed benzene rings.  
   
   
       6 . A process according to any of  claim 3 , wherein said first indolenine has additional condensed benzene rings bearing sulphonic groups or is quaternised with sulfoalkyl or carboxyalkyl groups.  
   
   
       7 . A process according to  claim 1 , wherein the intermediate hemicyanine from step a) is purified by extraction with a solvent suitable to extract the unreacted compounds of formula (II) without a substantial dissolution of the hemicyanine.  
   
   
       8 . A process according to  claim 7 , wherein said solvent is selected from the group consisting of ethyl acetate and chlorinated organic solvents and mixtures thereof.  
   
   
       9 . A process according to  claim 8  wherein said solvent is selected from the group consisting of methylene chloride, chloroform, 1, 1, 1-trichloro ethane and mixtures thereof.  
   
   
       10 . A process according to  claim 1  for preparing an asymmetric indocyanine dye of formula:  
     
       
         
         
             
             
         
       
     
     wherein 
 Q is a methine bridge with 3 or 5 carbon atoms  
 R 1  is hydrogen, SO 3   13   or —COOH,  
 R 2  and R 3  independently are H or SO 3   —  M +   
 M is a monovalent metal  
 R 4  is C 1 -C 12  alkyl, preferably C 1 -C 4  alkyl or (CH 2 ) m SO 3   −  with  
 m=1 to 12, preferably 1 to 4,  
 W is alkylene having from 1 to 18 carbon atoms, preferably 1 to 5 carbon atoms or is (CH 2 —CH 2 —O) n  CH 2 —CH 2 — wherein n is 1 to 5 and R 5  is a functional group selected from the group consisting of carboxyl, carbonyl(aldehyde), hydroxyl, amino, sulphydryl, glicidyl, maleimide, imidazolyl carbamoyl, succinimidyl ester, phosphoramidite, isothiocyanate, anhydride, haloacetamido, sulphonyl halide, acid halide, hydrazide, phthalimidyl ester and naphthalimydyl ester.  
 
   
   
       11 . A process according to  claim 1  for preparing an asymmetrical indocyanine dye selected from the group consisting of:  
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
     
   
   
       12 . A process for preparing a hemicyanine, comprising the step of: 
 reacting a quaternised indolenine or substituted indolenine with a compound of the formula (II)                          or hydrochloride thereof,    wherein n is 0 or 1    Ph is phenyl or substituted phenyl    X is hydrogen, halogen or alkyl, preferably chlorine, in a solvent selected from the group consisting of acetic acid, acetic anhydride and mixtures thereof in the presence of acetyl chloride.    
   
   
       13 . An asymmetrical indocyanine having the formula (I)  
     
       
         
         
             
             
         
       
     
     wherein 
 Q is a methine bridge with 3 or 5 carbon atoms  
 R 1  is hydrogen, SO 3   31   or —COOH,  
 R 2  and R 3  independently are H or SO 3   −  M +   
 M is-a monovalent metal  
 R 4  is C 1 -C 12  alkyl, preferably C 1 -C 4  alkyl or (CH 2 ) m SO 3   −  with  
 m=1 to 12, preferably 1 to 4,  
 W is alkylene having from 1 to 18 carbon atoms, preferably 1 to 5 carbon atoms or is (CH 2 —CH 2 —O) n  CH 2 —CH 2 — wherein n is 1 to 5 and R 5  is a functional group selected from the group consisting of carboxyl, carbonyl(aldehyde), hydroxyl, amino, sulphydryl, glicidyl, maleimide, imidazolyl carbamoyl, succinimidyl ester, phosphoramidite, isothiocyanate, anhydride, haloacetamido, sulphonyl halide, acid halide, hydrazide, phthalimidyl ester and naphthalimydyl ester.  
 
   
   
       14 . An asymmetrical indocyanine having the formula selected from the group consisting of