Cytotoxic sesquiterpenes from luminescent mushroom Neonothopanus nambi

Four new aristolane sesquiterpenes named nambinones A–C (1–3) and 1-epi-nambinone B (4), a new sesquiterpene, nambinone D (5), a known compound, aurisin A (6) as well as a new dimeric sesquiterpene, aurisin K (7), were isolated from two isolates of luminescent mushroom, Neonothopanus nambi, PW1 and PW2. These structures were established on the basis of spectroscopic evidence. The relative configuration of 6 was determined by X-ray crystallographic analysis. Compounds 6 and 7 exhibited antimalarial activity against Plasmodium falciparum and antimycobacterial activity against Mycobacterium tuberculosis. Compounds 3, 6, and 7 showed cytotoxicity against NCI-H187 cancer cell lines. In addition, 6 and 7 showed cytotoxicity against the cholangiocarcinoma cell lines.