A Formal Synthesis of l-.ALPHA.-Santonin from Chiral .ALPHA.,.BETA.-Epoxyeudesmanolide via Enzyme-Cayalyzed Hydrolysis.
作者:Nobuko SHIMIZU、Hiroyuki AKITA、Takeshi OISHI、Seiichi INAYAMA
DOI:10.1248/cpb.42.1160
日期:——
(4S, 5R)-Epoxy-(3S)-hydroxy-(10S)-7α, 11βH-eudesman-6α, 12-olide 4__- and (4R, 5S)-epoxy-(3S)-hydroxy-(10R)-7β, 11αH-eudesman-6β, 12-olide 5__- were obtained from (±)-3__- using yeast and (3S)-acetoxy-(4S, 5R)-epoxy-(10S)-7α, 11βH-eudesman-6α, 12-olide 8__- was produced from (±)-8__- using lipase, respectively. New total syntheses of l-α-santonin (9) and its Δ4(14)-isomers (10 and 11) were accomplished by a short step synthesis using the optically active key intermediate (10S)-8__- (prepared by asymmetric hydrolysis of (±)-8__-).
通过酵母处理(±)-3__-,分别得到了(4S, 5R)-环氧-(3S)-羟基-(10S)-7α, 11βH-桉烷-6α, 12-内酯4__-和(4R, 5S)-环氧-(3S)-羟基-(10R)-7β, 11αH-桉烷-6β, 12-内酯5__-;通过脂肪酶处理(±)-8__-,制备了(3S)-乙酰氧基-(4S, 5R)-环氧-(10S)-7α, 11βH-桉烷-6α, 12-内酯8__-。通过使用手性关键中间体(10S)-8__-(通过不对称水解(±)-8__-制备)的短步骤合成,成功完成了l-α-山道年(9)及其Δ4(14)异构体(10和11)的新全合成。