Synthetic Approaches to Novel Thiosugar Scaffolds Containing α,β-Unsaturated Carbonyl Groups
作者:Nuno M. Xavier、Paulo J. A. Madeira、M. Helena Florêncio、Amélia P. Rauter
DOI:10.1002/ejoc.200900573
日期:2009.10
3-uloses by practical and reliable approaches. The reaction sequence used for the bicyclic fused derivatives involved Wittig olefination of protected pento- or hexofuran-3-uloses, introduction of a sulfhydryl group at C-5 of the intermediate unsaturated ester and acid-promoted deprotection, which allowed intramolecular lactonization and conversion into the 5-thiopyranose form. For the synthesis of
通过简单有效的策略,合成了含有 α,β-不饱和羰基官能团的新型高度官能化硫糖衍生物。5-硫糖融合的丁烯内酯和 5-thiohex-1-enopyran-3-ulose 是通过实用和可靠的方法从容易获得的起始 3-ulose 构建的。用于双环稠合衍生物的反应序列包括受保护的戊-或 hexofuran-3-uloses 的 Wittig 烯化、在中间体不饱和酯的 C-5 处引入巯基和酸促进脱保护,这允许分子内内酯化并转化为5-噻喃型。为了合成 5-thiohex-1-enopyran-3-ulose,在 C-5 处引入了一个巯基官能团,在 1,2:5 衍生的掩蔽 3-ulose 上,6-di-O-isopropylidene-α-D-ribo-hexofuranos-3-ulose。酸水解将平衡移向 5-thiopentopyran-3-ulose,其在吡啶介导的乙酰化作用下经历 1,2-消除乙酸,得到所需的