Photocyclization of Enamides. XXXIV. A Practical Total Synthesis of Aromatic Yohimboid Alkaloids, Oxogambirtannine and Naucleficine

Abstract

Total synthesis of naucleficine (3a) was accomplished for the first time via an alkaloid, oxogambirtannine (3b), which was efficiently prepared by photocyclization of the o-methoxy-enamide 2b. The method is a practical one, suitable for large-scale preparation.