First total synthesis of a new pyrrolizidine alkaloid, amphorogynine A
作者:Hidemi Yoda、Takahisa Egawa、Kunihiko Takabe
DOI:10.1016/s0040-4039(03)00070-4
日期:2003.2
An efficient and stereodefined strategy is described for the first asymmetric synthesis of a new type of pyrrolizidinealkaloids, amphorogynine A and its 1-epi-isomer. The key 2,4-disubstituted pyrrolidine ring was constructed by elaboration of the chiral lactam derivative incorporating the d-malic acid-derived skeleton through asymmetric cis-allylation of the functionalized allysilane.
A direct approach to the synthesis of poly-hydroxylated piperidine and pyrrolidine peptidomimetics is described. The presented strategy is based on one-pot reduction of sugar-derived lactams with Schwartz's reagent followed by a multicomponent Ugi-Joullie reaction.