Cytotoxic pentacyclic and tetracyclic aromatic sesquiterpenes from phomopsis archeri

Abstract

Three new sesquiterpenes, named phomoarcherins A-C (1-3), and four known compounds, kampanol A (4), R-mevalonolactone, ergosterol, and ergosterol peroxide, were isolated from the endophytic fungus Phomopsis archeri. These structures were established on the basis of spectroscopic evidence. The structure and absolute configuration of 1 were confirmed by X-ray crystallographic analysis of its p-bromobenzoate derivative (1a). Compounds 1-4 showed cytotoxicity against five cholangiocarcinoma cell lines (0.1-19.6 μg/mL), while 1 and 2 exhibited weak cytotoxicity against the KB cell line with IC50 values of 42.1 and 9.4 μg/mL, respectively. In addition, compound 2 showed antimalarial activity against Plasmodium falciparum with an IC50 value of 0.79 μg/mL. © 2011 The American Chemical Society and American Society of Pharmacognosy.