Reactions of N-, S- and O-Nucleophiles with 3,4,6-Tri-O-benzyl-D-glucal Mediated by Triphenylphosphane Hydrobromide versus Those with HY Zeolite
作者:Amélia P. Rauter、Tânia Almeida、Ana I. Vicente、Verónica Ribeiro、João C. Bordado、João P. Marques、Fernando Ramôa Ribeiro、Maria J. Ferreira、Conceição Oliveira、Michel Guisnet
DOI:10.1002/ejoc.200500916
日期:2006.5
straightforward synthesis of a variety of biomolecules, in moderate to high yield, with the first use of triphenylphosphane hydrobromide for N- and S-glycosylation. An alternative method for C–O and C–S bond formation uses HY zeolite to promote theFerrier rearrangement of 3,4,6-tri-O-benzyl-D-glucal to give exclusively the corresponding 2,3-unsaturated α-O- and α-S-glycosides in moderate yields. (© Wiley-VCH
通过 1,5-anhydro-3,4,6-tri-O-benzyl-2-deoxy-D-arabino-hex-1-enitol (3,4,6- tri-O-benzyl-D-glucal) 与 N-亲核试剂,使用三苯基膦氢溴酸盐作为二氯甲烷或 THF 中的催化剂。2-脱氧-S-和-O-糖苷也用硫醇、甾醇、类黄酮、醇和糖作为亲核试剂制备,具有α-立体选择性。甾醇、类黄酮、糖和吲哚等空间要求较高的试剂在二氯甲烷中仅产生 α-异头物,而 THF 中的嘌呤核苷作为异头物混合物获得,同时保持 α-立体选择性。这个过程导致了各种生物分子的简单和直接的合成,产量中等至高,首次使用三苯基膦氢溴化物进行 N-和 S-糖基化。C-O 和 C-S 键形成的另一种方法是使用 HY 沸石促进 3,4,6-三-O-苄基-D-glucal 的费里叶重排,专门生成相应的 2,3-不饱和 α-O-和 α-S-糖苷的产量适中。(©