Enantioselective Synthesis of α-Alkylmalates as the Pharmacophoric Group of Several Natural Alkaloids and Glycosides
作者:Serry A. A. El Bialy、Holger Braun、Lutz F. Tietze
DOI:10.1002/ejoc.200500065
日期:2005.7
A general enantioselective synthesis of α-alkylmalates found in Cephalotaxus and Orchidaceae species is described. This preparation is based upon Seebach’s procedure for the alkylation of D-malic acid with self-regeneration of stereogenic centers. Reaction of the dioxolanone 8a with LiHMDS and allyl halides as well as benzyl bromide gave 10 and 14, respectively, which could be transformed into enantiopure
描述了在 Cephalotaxus 和 Orchidaceae 物种中发现的 α-烷基苹果酸酯的一般对映选择性合成。这种制备基于 Seebach 的 D-苹果酸烷基化程序,具有立体中心的自我再生。二氧戊环酮 8a 与 LiHMDS 和烯丙基卤化物以及苄基溴的反应分别得到 10 和 14,它们可以转化为对映纯的α-烷基苹果酸酯 13、15、18 和 19。此外,还制备了 20 型对映纯呋喃. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)