Niphatesines A–D, new antineoplastic pyridine alkaloids from the okinawan marine sponge Niphates sp.

Abstract

Four new pyridine alkaloids, niphatesines A–D (1–4), with potent antineoplastic activity were isolated from the Okinawan marine sponge Niphates sp. and their structures were elucidated on the basis of spectroscopic data.