Heterochain polymers based on natural amino acids. Synthesis and enzymatic hydrolysis of regular poly(ester amide)s based on bis( L ‐phenylalanine) α,ω‐alkylene diesters and adipic acid

Novel biodegradable regular poly(ester amide)s were synthesized by polycondensation of p ‐toluenesulfonic acid salts of bis(phenylalanine) α,ω‐alkylene diesters ( 1 ) with bis( p ‐nitrophenyl) adipate under mild conditions in organic solvents in the presence of triethyl amine as acid acceptor. Enzymatic hydrolysis (α‐chymotrypsinolysis) of the starting salts 1 , the model bis(ester acetamide)s 2 and the obtained poly(ester amide)s 3 was investigated at 37°C and pH 8 using potentiometric titration. It was established that the hydrolysis rate increased with elongation of the α,ω‐alkylene chain. A strong noncovalent immobilization of the enzyme on the polymeric surface was observed.