Carotane-type sesquiterpenes from cultures of the insect pathogenic fungus Isaria fumosorosea

Abstract

Two new carotane-type sesquiterpenes named trichocaranes E (1) and F (2), along with two known ones CAF-603 (3) and trichocarane C (4), were isolated from cultures of the insect pathogenic fungus Isaria fumosorosea. Their structures and relative configurations were elucidated by extensive spectroscopic analysis and X-ray crystallography. Compounds 1–3 showed potent cytotoxic activities against six tumor cell lines MDA, MCF-7, SKOV-3, Hela, A549, HepG2 with IC₅₀ values in a concentration range of 0.1–6.0 μg/ml.

Keywords:

• Isaria fumosorosea
• carotane sesquiterpenes
• cytotoxicity