Scopularides A and B, two new cyclodepsipeptides from the marine sponge-derived fungus Scopulariopsis brevicaulis

The Kieler Wirkstoffzentrum KiWiZ is devoted to the isolation and characterization of biologically active natural products from marine-derived microorganisms. We report here on products from the fungus Scopulariopsis brevicaulis isolated from the marine sponge Tethya aurantium.

Despite the widespread distribution of Scopulariopsis spp., only one pyranol derivative and some methylarsines and -stibines were known so far from this genus. Our analyses revealed the presence of two novel cyclodepsipeptides, scopularides A (1) and B (2), which were isolated from a mycelium extract of the fungus by preparative HPLC as white microcrystalline powders along with the known tremorgenic alkaloid paxilline. The structures of the scopularides A and B were elucidated by NMR, MS, and chemical derivatization methods as cyclo(3-hydroxy-4-methyldecanoyl–Gly–l-Val– d-Leu– l-Ala–l-Phe) and cyclo(3-hydroxy-4-methyloctanoyl–Gly–l-Val–d-Leu–l-Ala–l-Phe) for scopularide A (1) and B (2), respectively.¹

References: 1. Yu, Z., et al. (2008) J. Nat. Prod., in press.