Oligopeptide linker intermediate and preparation method thereof

Abstract

The invention provides a new oligopeptide linker intermediate and a preparation method thereof. The preparation method of the oligopeptide intermediate is easily carried out under mild reaction conditions, and since almost no side reactions occur in the reaction, the method produces a high-purity product with fewer impurities and easy to be purified, achieving unexpected technical effects.

1 . An oligopeptide linker intermediate having the structure represented by formulas (1)-(4): 
       
         
           
           
               
               
           
         
         wherein, the AA 1 , AA 2 , AA 3 , AA 4  are any amino acid. 
       
     
     
         2 . The oligopeptide linker intermediate according to  claim 1 , wherein the AA 1 , AA 2 , AA 3 , and AA 4  are each independently selected from the group consisting of -valine- (-Val-), -citrulline -(-Cit-), -alanine- (-Ala-), -lysine- (-Lys-), -lysine(trityl)- (-Lys(Trt)-), -lysine(monomethoxytrityl)-(-Lys(Mmt)-), -lysine(fluorenylmethyloxycarbonyl)- (-Lys(Fmoc)-), -arginine- (-Arg-), -phenylalanine- (-Phe-), -glycine- (-Gly-), -leucine- (-Leu-) and -isoleucine- (-Ile-). 
     
     
         3 . The oligopeptide linker intermediate according to  claim 2 , wherein
 the -AA 1 -AA 2 - is selected from the group consisting of -valine-citrulline- (-Val-Cit-), -valine-alanine-(-Val-Ala-), -valine-lysine- (-Val-Lys-), -valine-lysine(trityl)- (-Val-Lys(Trt)-), -valine-lysine(monomethoxytrityl)-(-Val-Lys(Mmt)-), -valine-lysine(fluorenylmethyloxycarbonyl)-(-Val-Lys(Fmoc)-), -valine-arginine- (-Val-Arg-), -phenylalanine-citrulline-(-Phe-Cit-), -phenylpropyl-lysine- (-Phe-Lys-), -phenylalanine-lysine(trityl)-(-Phe-Lys(Trt)-), -phenylalanine-lysine(monomethoxytrityl)- (-Phe-Lys (Mmt)-), -phenylalanine-lysine (fluorenylmethyloxycarbonyl)- (-Phe-Lys(Fmoc)-), leucine-citrulline- (-Leu-Cit-), isoleucine-citrulline- (-Ile-Cit-) and -phenylalanine-arginine- (-Phe-Arg-);   the -AA 1 -AA 2 -AA 3 - is -phenylalanine-arginine-arginine-(-Ala-Arg-Arg-); and   the -AA 1 -AA 2 -AA 3 -AA 4 - is selected from the group consisting of -glycine-glycine-phenylalanine-glycine-(-Gly-Gly-Phe-Gly-), -glycine-phenylalanine-leucine-glycine- (-Gly-Phe-Leu-Gly-) and -alanine-leucine-alanine-leucine (-Ala-Leu-Ala-Leu-).   
     
     
         4 . The oligopeptide linker intermediate according to  claim 3 , wherein the oligopeptide linker intermediate includes the following structure: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         5 . An antibody-drug conjugate having a linker, wherein the precursor of the linker used in the antibody-drug conjugate is the oligopeptide linker intermediate according to  claim 1 . 
     
     
         6 . A method for preparing the oligopeptide linker intermediate according to  claim 1 , wherein the method for preparing the oligopeptide linker intermediate of formulas (1) to (3) comprising:
 1) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol and amino acid AA 1 , and then amino acid AA 2 , or amino acid AA 1 , amino acid AA 2  and amino acid AA 3  in sequence, or amino acid AA 1 , amino acid AA 2 , amino acid AA 3  and amino acid AA 4  in sequence, to obtain a 2-(trimethylsilyl)ethoxycarbonyl-oligopeptide condensate;   2) reacting the resulting 2-(trimethylsilyl)ethoxycarbonyl-oligopeptide condensate and p-aminobenzyl alcohol to obtain a 2-(trimethylsilyl)ethoxycarbonyl-oligopeptide-p-aminobenzyl alcohol condensate,   wherein the carbonylation reagent is any compound containing a carbonyl group; or   a method for preparing the oligopeptide linker intermediate of formula (4) comprising:   1′) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol and amino acid AA 1 , amino acid AA 2 , amino acid AA 3  and amino acid AA 4  in sequence, to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tetrapeptide condensate, wherein the carbonylation reagent is any compound containing a carbonyl group.   
     
     
         7 . The method according to  claim 6 , wherein the oligopeptide linker intermediate of formula (1) is obtained via the following reaction path: 
       
         
           
           
               
               
           
         
         wherein the method comprises the following steps: 
         1) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol and amino acid AA 1  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate; 
         2) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate and amino acid AA 2  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate; and 
         3) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate and p-aminobenzyl alcohol to obtain a 2-(trimethylsilyl)ethoxycarbonyl-dipeptide-p-aminobenzyl alcohol condensate. 
       
     
     
         8 . The method according to  claim 6 , wherein the oligopeptide linker intermediate of formula (2) is obtained via the following reaction path: 
       
         
           
           
               
               
           
         
         wherein the method comprises the following steps: 
         1) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol and amino acid AA 1  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate; 
         2) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate and amino acid AA 2  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate; 
         3) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate and amino acid AA 3  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate; and 
         4) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate and p-aminobenzyl alcohol to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tripeptide-p-aminobenzyl alcohol condensate. 
       
     
     
         9 . The method according to  claim 6 , wherein the oligopeptide linker intermediate of formula (3) is obtained via the following reaction path: 
       
         
           
           
               
               
           
         
         wherein the method comprises the following steps: 
         1) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol and amino acid AA 1  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate; 
         2) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate and amino acid AA 2  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate; 
         3) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate and amino acid AA 3  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate; 
         4) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate and amino acid AA 4  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tetrapeptide condensate; and 
         5) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-tetrapeptide condensate and p-aminobenzyl alcohol to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tetrapeptide-p-aminobenzyl alcohol condensate. 
       
     
     
         10 . (canceled) 
     
     
         11 . The method according to  claim 6 , wherein the oligopeptide linker intermediate of formula (4) is obtained via the following reaction path: 
       
         
           
           
               
               
           
         
         1) performing a condensation reaction between a carbonylation reagent, 2-(trimethylsilyl)ethanol, and amino acid AA 1  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate; 
         2) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-amino acid condensate and amino acid AA 2  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate; 
         3) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-dipeptide condensate and amino acid AA 3  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate; and 
         4) performing a condensation reaction between the 2-(trimethylsilyl)ethoxycarbonyl-tripeptide condensate and amino acid AA 4  to obtain a 2-(trimethylsilyl)ethoxycarbonyl-tetrapeptide condensate. 
       
     
     
         12 . The method according to  claim 6 , wherein
 the carbonylation reagent has a structure of formula (5):   
       
         
           
           
               
               
           
         
         wherein: 
         the R 1  and R 2  are each independently selected from the group consisting of: 
       
       
         
           
           
               
               
           
         
       
     
     
         13 . The method according to  claim 12 , wherein the carbonylation reagent is selected from the group consisting of: 
       
         
           
           
               
               
           
         
       
     
     
         14 . The method according to  claim 6 , wherein the AA 1 , AA 2 , AA 3 , and AA 4  are each independently selected from the group consisting of: -valine-(-Val-), -citrulline -(-Cit-), -alanine- (-Ala-), -lysine- (-Lys-), -lysine(trityl)- (-Lys(Trt)-), -lysine(monomethoxytrityl)-(-Lys(Mmt)-), -lysine(fluorenylmethyloxycarbonyl)- (-Lys(Fmoc)-), -arginine- (-Arg-), -phenylalanine- (-Phe-), -glycine- (-Gly-), -leucine- (-Leu-) and -isoleucine- (-Ile-). 
     
     
         15 . The method according to  claim 14 , wherein
 the -AA 1 -AA 2 - is selected from the group consisting of -valine-citrulline- (-Val-Cit-), -valine-alanine-(-Val-Ala-), -valine-lysine- (-Val-Lys-), -valine-lysine(trityl)- (-Val-Lys(Trt)-), -valine-lysine(monomethoxytrityl)-(-Val-Lys(Mmt)-), -valine-lysine(fluorenylmethyloxycarbonyl)-(-Val-Lys(Fmoc)-), -valine-arginine- (-Val-Arg-), -phenylalanine-citrulline-(-Phe-Cit-), -phenylpropyl-lysine- (-Phe-Lys-), -phenylalanine-lysine(trityl)-(-Phe-Lys(Trt)-), -phenylalanine-lysine(monomethoxytrityl)- (-Phe-Lys (Mmt)-), -phenylalanine-lysine (fluorenylmethyloxycarbonyl)- (-Phe-Lys(Fmoc)-), leucine-citrulline- (-Leu-Cit-), isoleucine-citrulline- (-Ile-Cit-) and -phenylalanine-arginine- (-Phe-Arg-);   the -AA 1 -AA 2 -AA 3 - is -phenylalanine-arginine-arginine-(-Ala-Arg-Arg-); and   the -AA 1 -AA 2 -AA 3 -AA 4 - is selected from the group consisting of -glycine-glycine-phenylalanine-glycine-(-Gly-Gly-Phe-Gly-), -glycine-phenylalanine-leucine-glycine- (-Gly-Phe-Leu-Gly-), and -alanine-leucine-alanine-leucine (-Ala-Leu-Ala-Leu-).   
     
     
         16 . The method of  claim 15 , wherein the -AA 1 -AA 2 - is selected from the following structures: 
       
         
           
           
               
               
           
         
         
           
           
               
               
           
         
         
           
           
               
               
           
         
       
     
     
         17 . The method according to  claim 15 , wherein the -AA 1 -AA 2 -AA 3 - is 
       
         
           
           
               
               
           
         
       
     
     
         18 . The method according to  claim 15 , wherein the -AA 1 -AA 2 -AA 3 -AA 4 - is selected from the following structures: 
       
         
           
           
               
               
           
         
       
     
     
         19 . The method according to  claim 6 , wherein solvent used in the condensation reaction is a polar solvent or non-polar solvent; preferably, the solvent is one or more selected from the group consisting of tetrahydrofuran, dioxane, acetonitrile, DMF, DMSO, DMAc, DMPU, HMPA, ethylene glycol dimethyl ether, diethyl ether, tert-butyl methyl ether, tert-butanol, water, ethyl acetate, methanol, ethanol, isopropanol, dichloromethane, chloroform, and carbon tetrachloride; more preferably, the solvent is one or more selected from the group consisting of tetrahydrofuran, dioxane, acetonitrile, DMF, DMSO, water, methanol, dichloromethane, chloroform, carbon tetrachloride and ethanol. 
     
     
         20 - 21 . (canceled)