From the leaves of Tonduzia pittieri (Alstonia pittieri), nine alkaloids have been identified. Four are novel: 11-methoxyvincamedine, 11-[10-(11-methoxy-17-epi-vincamajinyl)]-vincorine, 11-[10-(11-methoxyvincamajinyl)]-vincorine, 11-[10-(11-methoxyvincamedinyl)]-vincorine. The five others are known: vincorine, 11-methoxy-17-epi-vincamajine, picrinine, 18-hydroxycabucraline and cabufiline. © 1992.