The syntheses of pyrrolidine alkaloids (-)-1 and (+)-3 were accomplished in 47% and 60% overall yield from 2-azido-2-deoxy-l-idonate 5, while piperidine alkaloids (-)-2 and (+)-4 were obtained in 51% and 53% overall yield from the same starting material. Key step includes iodine promoted one-pot cyclization, and selective deprotection of isopropylidene and 9-phenylfluoren-9-yl (Pf) group.
从 2-azido-2-deoxy-l-idonate 5 合成
吡咯烷
生物碱 (-)-1 和 (+)-3 的总收率分别为 47% 和 60%,而从相同的起始原料合成
哌啶生物碱 (-)-2 和 (+)-4 的总收率分别为 51% 和 53%。关键步骤包括
碘促进的一锅环化,以及异亚丙基和
9-苯基芴-9-基 (Pf) 基团的选择性脱保护。