Enzymatic Synthesis Of Chiral Polyamide Via Condensation Of Natural Source Amino Acid Diesters And Diamine

Enzymatic synthesis of chiral polyesters has been a powerful tool in the field of polymer chemistry. At the meantime, enzymatic polymerization for preparing chiral polyamides is rare. Herein, an efficient strategy for the preparing of optically pure polyamide via lipase-catalyzed condensation between natural source amino acid diesters and diamines is demonstrated. The highest molecular weight of l- configuration targeting optically pure polyamide can reach up to 8.5 x 10(3) g mol(-1) (M-w,M- = 2.18). Moreover, both d- and l- configuration of chiral polyamides can be obtained without complex protein modification or substrate engineering. The molecular weight of d- configuration chiral polyamide can also reach up to 7.5 x 10(3) g mol(-1) (M-w, = 1.95). The scanning electron microscopy is applied for test the microstructure of chiral polyamide. By precipitating in acetone/N,N-dimethyformamide (DMF) solvent system, a microsphere and nanotube microstructure can be observed with the changing of acetone/DMF ratio.