Colletotrin: a sesquiterpene lactone from the endophytic fungus Colletotrichum gloeosporioides associated with Trichilia monadelpha

A new sesquiterpene lactone, namely colletotrin (1), together with two known fungal metabolites (2, 3), was obtained from a rice culture of Colletotrichum gloeosporioides, an endophytic fungus isolated from the stem bark of Cameroonian medicinal plant Trichilia monadelpha (Meliaceae). The structure of the new compound was established on the basis of extensive NMR analysis (1H, 13C, heteronuclear single-quantum coherence and heteronuclear multiple-bond correlation) completed by high-resolution electrospray ionization mass spectroscopy results and by comparison of these data with those of related compounds described in the literature. Their cytotoxic and antibacterial activities against the mouse lymphoma L5178Y cell line and Mycobacterium tuberculosis, respectively, were also evaluated. This study is the first report on the isolation of fungal metabolites from endophytic fungi associated with T. monadelpha (Meliaceae).