New Oblongolides Isolated from the Endophytic Fungus Phomopsis sp. from Melilotus dentata from the Shores of the Baltic Sea

Thirteen new metabolites, namely oblongolides B–M (2–13) and 4-[5-(1-hydroxyethyl)furan-2-yl]-4-oxobutanoic acid (14), together with the six known compounds phomopsolide B (15), alternariol dimethyl ether (16), alternariol monomethyl ether (17), the mycotoxin alternariol (18), ergosterol (19), and 5α,8α-epidioxyergosterol (20) were isolated from the endophytic fungus Phomopsis sp. The new biologically active norsesquiterpene γ-lactones differ in their degree of substitution, saturation, and substituent pattern from the known oblongolide 1. Their structures were determined by means of spectroscopic data including HREIMS, 1H NMR, 13C NMR, 2D NMR (HMQC, HMBC, NOESY) and X-ray single crystal analysis. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)