SYNTHESIS OF PANCRASTISTATIN

摘要

(+)-Narciclasine (2), available in quantity from certain Amaryllidaceae species or by total synthesis, is employed as relay for a ten step synthetic conversion (3.6 % overall yield) to natural (+)-pancratistatin (1a). The key procedures involve the epoxidation of natural (+)-narciclasine (2) to an epoxide (6), reduction of the epoxide (6) to diol (8), formation of cyclic sulfate (12) and its ring opening with cesium benzoate followed by saponification of the benzoate to afford (+)-pancratistatin (1a).