A series of chiral lipophilic Cu(Ⅱ) complexes were investigated as catalysts for the enantioselective hydrolysis of R(S)-p-nitrophenyl N-dodecanoyl-phenylalaninate in micelles. The highest enantioselectivity (kR/ks=7...A series of chiral lipophilic Cu(Ⅱ) complexes were investigated as catalysts for the enantioselective hydrolysis of R(S)-p-nitrophenyl N-dodecanoyl-phenylalaninate in micelles. The highest enantioselectivity (kR/ks=7. 81) was observed in a mixed micellar system composed of 1-Cu(Ⅱ) and Brij35.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
Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammo...Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammonia solution and subsequent coating with 3,4-dihydroxylaldehyde. Magnetic Fe304 nanoparticles modified with 3,4-dihydroxylaldehyde bonded lipase efficiently（47 mg/g）. The resulting magnetic-lipase is active（0.68 μmol·min^-1·mg^-1） and enantioselective（e.e, of the product 〉98%） in the hydrolysis of racemic 1-phenylethyl acetate. Furthermore, as a heterogeneous catalyst, the magnetic-lipase can be magnetically recycled, and a retained activity of 48% was obtained even after 6 cycles.展开更多
文摘A series of chiral lipophilic Cu(Ⅱ) complexes were investigated as catalysts for the enantioselective hydrolysis of R(S)-p-nitrophenyl N-dodecanoyl-phenylalaninate in micelles. The highest enantioselectivity (kR/ks=7. 81) was observed in a mixed micellar system composed of 1-Cu(Ⅱ) and Brij35.
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.
基金Supported by the National Natural Science Foundation of China（No.21203017）, the Open Fund of State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences（No.N-11-3）, the Program for Liaoning Excellent Talents in University, China and the Fundamental Research Funds for the Central Universities, China（No.DC201502020304）.
文摘Magnetic lipase was prepared by a facial and cost-effective method. Lipase from Pseudomonase cepacia was covalently linked to Fe304 nanoparticles, which were produced by co-precipitating Fe^2＋ and Fe^3＋ ions in ammonia solution and subsequent coating with 3,4-dihydroxylaldehyde. Magnetic Fe304 nanoparticles modified with 3,4-dihydroxylaldehyde bonded lipase efficiently（47 mg/g）. The resulting magnetic-lipase is active（0.68 μmol·min^-1·mg^-1） and enantioselective（e.e, of the product 〉98%） in the hydrolysis of racemic 1-phenylethyl acetate. Furthermore, as a heterogeneous catalyst, the magnetic-lipase can be magnetically recycled, and a retained activity of 48% was obtained even after 6 cycles.
