A novel reaction\|enzymatic ammonolysis discovered in the mid of 1990s has been demonstrated to be a very promising alternative in the preparation of optically pure compounds. The effects of organic solvent, initial w...A novel reaction\|enzymatic ammonolysis discovered in the mid of 1990s has been demonstrated to be a very promising alternative in the preparation of optically pure compounds. The effects of organic solvent, initial water activity, temperature and additives on lipase Novozym435\|catalyzed enantioselective ammonolysis of racemic phenylglycine methyl ester were investigated systematically in this paper. Enzymatic reaction of ammonolysis showed higher activity and enantioselectivity than the corresponding reaction of hydrolysis and alcoholysis.展开更多
The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis...The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis of ibuprofen methyl ester was obtained against an immunogen consisting of tetrahedral phosphonate hapten attached to bovine serum albumin (BSA). The catalytic activity of the catalytic antibody in the water-miscible organic-solvent system composed of a buffer solution and N, N-dimethylformamide (DMF) was studied. With 6% DMF in the buffer solution (containing catalytic antibody 0.25 μmol, 0.2 mol·L-1 phosphate buffer, pH 8) at 37°C for 10 h, a good conversion (48.7%) and high enantiomeric excess (>99%) could be reached. The kinetic analysis of the cata-lytic antibody-catalyzed reaction showed that the hydrolysis in the water-miscible organic-solvent system with DMF in buffer solution followed the Michaelis-Menten kinetics. The catalytic efficiency (Kcat/Km) was enhanced to 151.91 L·mmol-1·min-1, twice as large as that for the buffer solution only.展开更多
文摘A novel reaction\|enzymatic ammonolysis discovered in the mid of 1990s has been demonstrated to be a very promising alternative in the preparation of optically pure compounds. The effects of organic solvent, initial water activity, temperature and additives on lipase Novozym435\|catalyzed enantioselective ammonolysis of racemic phenylglycine methyl ester were investigated systematically in this paper. Enzymatic reaction of ammonolysis showed higher activity and enantioselectivity than the corresponding reaction of hydrolysis and alcoholysis.
基金Supported by the Natural Science Foundation of Zhejiang Province (Y404353)
文摘The asymmetric hydrolysis of racemic ibuprofen ester is one of the most important methods for chiral separation of ibuprofen. In this work, a catalytic antibody that accelerates the rate of enantioselective hydrolysis of ibuprofen methyl ester was obtained against an immunogen consisting of tetrahedral phosphonate hapten attached to bovine serum albumin (BSA). The catalytic activity of the catalytic antibody in the water-miscible organic-solvent system composed of a buffer solution and N, N-dimethylformamide (DMF) was studied. With 6% DMF in the buffer solution (containing catalytic antibody 0.25 μmol, 0.2 mol·L-1 phosphate buffer, pH 8) at 37°C for 10 h, a good conversion (48.7%) and high enantiomeric excess (>99%) could be reached. The kinetic analysis of the cata-lytic antibody-catalyzed reaction showed that the hydrolysis in the water-miscible organic-solvent system with DMF in buffer solution followed the Michaelis-Menten kinetics. The catalytic efficiency (Kcat/Km) was enhanced to 151.91 L·mmol-1·min-1, twice as large as that for the buffer solution only.
