Cytochalasan syntheses: Synthesis of (17, 18)-17, 18-dihydroxy-10-(prop-2-YL)-14-methyl-[11]cytochalasa-6(7), 13z, 19E-triene-1, 21-dione; an isomer of aspochalasin C
作者:Andrew P. Craven、Hazel J. Dyke、Eric J. Thomas
DOI:10.1016/s0040-4020(01)83439-6
日期:1989.1
)-Δ3-pyrrolin-2-ones (36), Diels Alder cyclization occurred. The minor (8'Z)-pyrrolinone cyclized stereoselectively to give the adduct (39) which has the aspochalasan stereochemistry around the hydrogenated isoindolone nucleus. However the major (8')-pyrrolinone gave a mixture of and isomers (41) and (43) in which the undesired adduct (43) was the major component. Adduct (39) was converted into dihydroxyenone
上加热2的稀溶液:的(8' 1混合物) -和(8' )-3-(1- oxotrienyl)-Δ 3 -吡咯-2-酮(36),发生狄尔斯-阿尔德环化。将次要的(8'Z)-吡咯啉酮立体选择性地环化,得到加合物(39),该加合物在氢化的异吲哚酮核周围具有Aschachalasan立体化学。然而主要的(8' )-pyrrolinone给予了的混合物和异构体(41)和(43),其中不希望的加合物(43)是主要组分。加合物(39)转化为二羟烯酮(48),即天青素C(4)的(13,14)-异构体。