Fistulopsines A and B antiproliferative septicine-type alkaloids from Ficus fistulosa

Abstract

Two new septicine-type alkaloids, fistulopsines A and B (1 and 2), together with four known phenanthroindolizidine alkaloids ((+)-septicine, (+)-tylophorine, (+)-tylocrebrine, and (–)-3,6-didemethylisotylocrebrine) and (+)-(6S,9S)-vomifoliol, were isolated from the bark and leaves of Ficus fistulosa. The structures of these compounds were established by spectroscopic analysis. Fistulopsines A and B (1 and 2) showed in vitro growth inhibitory activities in HCT 116 and MCF7 cell lines with GI50 ranging between 2–7μM. Furthermore, both compounds 1 and 2 were found to predominantly arrest cells in G1 phase of the cell cycle without induction of apoptosis. HCT 116 cell cycle perturbation by both compounds was found to be transient (< 72h).