A MULTI-GRAM SYNTHESIS OF 1,2:5,6-DI-<i>O</i>-ISOPROPYLIDENE 3-<i>C</i>-TRIMETHYLSILYLMETHYL-α-D-ALLOFURANOSE. AN IMPROVED PREPARATION OF 3-<i>C</i>-HYDROXYMETHYL-α-D-GLUCO-AND 3-<i>C</i>-METHYL-α-D-ALLOFURANOSE DERIVATIVES
作者:Masuo Funabashi、Yukinori Ooshiro
DOI:10.1080/00304940209458080
日期:2002.8.1
3-C-hydroxymethyl-a-D-glucofuranose derivative (4): for which a key-intermediate is 1,2:5,6-di-O-isopropylidene-3-C-methylene-a-D-r~bo-hexofuranose (3).s Compound 3 has been prepared from a 3-ulose derivative l6 by the conventional Wittig reaction using methyltriphenylphosphonium bromide and n-butyllithium (or sodium hydride). However, the large-scale preparation of 3 via a Wittig reaction is not amenable
在天然产物合成中使用碳水化合物作为手性构件仍然是当代合成有机化学的一个具有挑战性的领域。作为我们研究与天然产物(如阿米普利霉素、paniculide C,2 和河豚毒素)3 相关的支链糖和环醇的工作的一部分,我们需要大量的 3-C-羟甲基-aD-呋喃葡萄糖衍生物 (4):其中关键中间体是 1,2:5,6-di-O-isopropylidene-3-C-methylene-aDr~bo-hexofuranose (3).s 化合物 3 已由 3-ulose 衍生物 l6 制备使用甲基三苯基溴化鏻和正丁基锂(或氢化钠)的常规 Wittig 反应。然而,通过 Wittig 反应大规模制备 3 在产率 (65-73%) 和大量正丁基锂的处理方面不适合;此外,3 柱层析纯化耗时,需要大量硅胶。因此,我们现在描述了通过 1,2:5,6-di-O-isopropidene-3-C-trimethylsi