title: Marilones A-C, phthalides from the sponge-derived fungus Stachylidium sp.
abstract: The marine-derived fungus Stachylidium sp. was isolated from the sponge Callyspongia sp. cf. C. flammea. Culture on a biomalt medium supplemented with sea salt led to the isolation of three new phthalide derivatives, i.e., marilones A-C (1-3), and the known compound silvaticol (4). The skeleton of marilones A and B is most unusual, and its biosynthesis is suggested to require unique biochemical reactions considering fungal secondary metabolism. Marilone A (1) was found to have antiplasmodial activity against Plasmodium berghei liver stages with an IC(50) of 12.1 µM. Marilone B (2) showed selective antagonistic activity towards the serotonin receptor 5-HT(2B) with a K(i) value of 7.7 µM.
authors.affiliation: Institute for Pharmaceutical Biology, University of Bonn, Nussallee 6, D-53115 Bonn, Germany.
authors.forename: Celso
authors.initials: C
authors.lastname: Almeida
authors.forename: Stefan
authors.initials: S
authors.lastname: Kehraus
authors.forename: Miguel
authors.initials: M
authors.lastname: Prudêncio
authors.forename: Gabriele M
authors.initials: GM
authors.lastname: König