Solution of the multistep pathway for assembly of corynanthean, strychnos, iboga, and aspidosperma monoterpenoid indole alkaloids from 19 <i>E</i> -geissoschizine

Abstract

Significance The multistep assembly of catharanthine and tabersonine from strictosidine remains poorly characterized for understanding the biochemistry of anticancer monoterpenoid indole alkaloid (MIA) biosynthesis in the medicinal plant, Catharanthus roseus . The seven-step pathway from 19 E -geissoschizine to four major MIA skeletons enables the assembly of catharanthine and tabersonine that complete the pathway for biosynthesis of the anticancer drugs, anhydrovinblastine and vincristine as well as for production of other biologically active MIAs.