Dimeric Indole Alkaloids. Vinblastine (Vincaleukoblastine), Vincristine (Leurocristine), and Their Derivatives

Abstract

The dimeric indole alkaloid vinblastine (vincaleukoblastine) (VLB), serendipitously discovered from Madagascan periwinkle (Catharanthus roseus syn. Vinca rosea, Apocynaceae) [1], exhibits remarkable cancer-fighting activity and contributed immensely to dispel the sufferings of human beings caused by certain types of cancer (see Chap. 33). Subsequent discovery of a few more dimeric indole alkaloids leurocristine (LCR) (also known as vincristine), leurosine, and leurosidine (vinrosidine) from the same plant (Fig. 28.1) and the study of their anticancer activities add another name vincristine to the list of important cancer-fighting drugs. The molecular structures of vincristine and vinblastine with some stereochemical reservations have been proposed from the studies of their spectral properties, degradations, characterizations of their degradation products, and on biogenetic grounds [2–4].