Chemical constituents from endophytic fungus Annulohypoxylon cf. stygium in leaves of Anoectochilus roxburghii (Wall.) Lindl.

The chemical investigation on endophytic fungus Annulohypoxylon cf. stygium in leaves of Anoectochilus roxburghii (Wall.) Lindl. Sixteen compounds were isolated and their structures were identified as palmarumycin CP2 ( 1 ), (-)-(3R)-mellein methyl ethe ( 2 ), kipukasins D ( 3 ), kipukasins E ( 4 ), secosterigmatocystin ( 5 ), notoamide D ( 6 ), notoamide C ( 7 ), (+)-versicolamide B ( 8 ), (-)-notoamide A ( 9 ), (-)-notoamide B ( 10 ), diorcinal ( 11 ), stephacidin A ( 12 ), sterigmatocystin ( 13 ), versiconol ( 14 ), dihydrosterigmatocystin ( 15 ), and averufanin ( 16 ) respectively by spectroscopic analysis and comparison with literature data. All the compounds were isolated from Annulohypoxylon genus for the first time. Compounds 1 and 13 showed selective cytotoxic activities against HepG2, Hela, MCF-7 and HT-29.