Synthesis of Calystegine B2, B3, and B4 Analogues: Mapping the Structure-Glycosidase Inhibitory Activity Relationships in the 1-Deoxy-6-oxacalystegine Series
作者:M. Isabel García-Moreno、Carmen Ortiz Mellet、José M. García Fernández
DOI:10.1002/ejoc.200300731
日期:2004.4
A practical synthesis of ring-modified calystegine analogues with a 6-oxa-nor-tropane structure has been developed. The methodology relies on the ability of the masked carbonyl group of hexose precursors to act as the electrophilic target for the nitrogen atom of pseudoamide (urea or thiourea) groups located at the C-5 position through the open-chain aldehyde form. The resulting piperidine species
已开发出具有 6-oxa-nor-tropane 结构的环修饰 calystegine 类似物的实用合成方法。该方法依赖于己糖前体的掩蔽羰基作为位于 C-5 位置的假酰胺(脲或硫脲)基团的氮原子通过开链醛形式的亲电目标的能力。得到的哌啶类经历涉及 6-OH 的自发分子内糖基化反应,前提是得到的双环氨基缩醛满足异头效应。由此获得的亚氨基糖模拟物的羟基化特征可以通过单糖模板的明智选择来改变。该策略的有效性已通过制备 1-deoxy-6-oxa-(+)-calystegine B2、(-)-B4 的 N-硫代氨基甲酰基和 N-氨基甲酰基衍生物得到证明,(+)-B3 和 (-)-B2 来自 L-ido、L-gulo、L-altro 和 D-ido 前体。所需的硫脲和脲是通过与异硫氰酸酯的偶联反应或与三苯基膦和异硫氰酸酯的串联 Staudinger-aza-Wittig 型反应,然后将水添加到 5-氨基-或