Mine Yurie, Zhang Lin, Fukunaga Kimitoshi, Sugimura Yoshiaki
Department of Applied Chemistry and Chemical Engineering, Faculty of Engineering, Yamaguchi University, 2-16-1 Tokiwadai, Ube, 755-8611, Japan.
Biotechnol Lett. 2005 Mar;27(6):383-8. doi: 10.1007/s10529-005-1527-1.
The solvent effects of cyclopentyl methyl ether (CPME) on the reaction rates and enzyme enantioselectivity in the enantioselective transesterifications of racemic 6-methyl-5-hepten-2-ol (racemic sulcatol: SUL) and racemic 2,2-dimethyl-1,3-dioxolane-4-methanol (racemic solketal: SOL) with a series of enol esters catalyzed by Pseudomonas cepacia lipase co-lyophilized with cyclodextrins (alpha-, beta-, gamma-, partially methylated beta-, and 2,3,6-tri-O-methyl-beta-cyclodextrin: alphaCyD; betaCyD; gammaCyD; Me1.78betaCyD; Me3betaCyD) were investigated and compared with those in diisopropyl ether (IPE). In the case of SUL, enzyme activities of the co-lyophilizate with Me1.78betaCyD in CPME were lower than those in IPE with every acyl source, however, the absolute enantiopreference was shown in the transesterification with vinyl butyrate (VBR) in IPME. When the substrates were SOL and VBR, the enzyme activities in CPME were greatly enhanced as high as 1.6-9.8-fold, while the enantioselectivities in CPME were comparable to those in IPE.
研究了环戊基甲基醚(CPME)对消旋6-甲基-5-庚烯-2-醇(消旋紫苏醇:SUL)和消旋2,2-二甲基-1,3-二氧戊环-4-甲醇(消旋索酮醇:SOL)与一系列烯醇酯在由与环糊精(α-、β-、γ-、部分甲基化β-和2,3,6-三-O-甲基-β-环糊精:αCyD;βCyD;γCyD;Me1.78βCyD;Me3βCyD)共冻干的洋葱假单胞菌脂肪酶催化下的对映选择性酯交换反应中反应速率和酶对映选择性的溶剂效应,并与在二异丙醚(IPE)中的效应进行了比较。对于SUL,在CPME中与Me1.78βCyD共冻干物的酶活性在每种酰基源下都低于在IPE中的活性,然而,在IPME中与丁酸乙烯酯(VBR)的酯交换反应中显示出绝对对映选择性。当底物为SOL和VBR时,CPME中的酶活性大大提高,高达1.6 - 9.8倍,而CPME中的对映选择性与IPE中的相当。