Regioselective enzymatic hydrolysis of acetylated pyranoses and pyranosides using immobilised lipases. An easy chemoenzymatic synthesis of α- and β-d-glucopyranose acetates bearing a free secondary C-4 hydroxyl group
作者:Marco Terreni、Raul Salvetti、Laura Linati、Roberto Fernandez-Lafuente、Gloria Fernández-Lorente、Agatha Bastida、José M. Guisan
DOI:10.1016/s0008-6215(02)00113-1
日期:2002.10
only in the 6- and 1-positions, respectively. Furthermore, a new one-pot chemoenzymatic approach has been developed in order to obtain alpha- and beta-protected glucopyranoses bearing a free secondary C-4 hydroxyl group. For instance, 1,2,3,6-tetra-O-acetyl-alpha-D-glucopyranose was easily synthesised in good overall yield (70%) starting from 1,2,3,4,6-penta-O-acetyl-alpha-D-glucopyranose by regioselective
仅具有一个游离羟基的被保护的糖是合成大量糖衍生物的有用的结构单元。为了避免经典化学合成的问题,我们研究了不同的完全乙酰化的吡喃葡萄糖和糖吡喃糖苷的区域选择性酶水解。主要的挑战是仅在一个位置获得底物的水解,具有高区域选择性,同时还要避免进一步水解为部分乙酰化的糖。固定在辛基琼脂糖上的皱纹假丝酵母(CRL)和荧光假单胞菌(PFL)脂肪酶(EC 3.1.1.3)仅分别在6位和1位提供区域选择性水解。此外,为了获得带有游离仲C-4羟基的α-和β-保护的吡喃葡萄糖,已经开发了一种新的一锅化学酶法。例如,从1,2,3,4,6-戊五-O-乙酰基开始,可以以良好的总收率(70%)轻松合成1,2,3,6-四-O-乙酰基-α-D-吡喃葡萄糖-α-D-吡喃葡萄糖通过CRL催化的6位区域选择性酶水解,然后进行温度和pH控制的酰基迁移。