Mycophenolic derivatives from Eupenicillium parvum.

A new compound, euparvic acid (1, C(14)H(16)O(6)), and the known compounds 5,7-dihydroxy-4-methylphthalide (2), 6-(3-carboxybutyl)-7-hydroxy-5-methoxy-4-methylphthalan-1-one (3), 6-(5-carboxy-3-methylpent-2-enyl)-7-hydroxy-5-methoxy-4-methylphthalan-1-one (4), and 6-(5-carboxy-4-hydroxy-3-methylpent-2-enyl)-7-hydroxy-5-methoxy-4-methylphthalan-1-one (5) were isolated from the EtOAc extract of Eupenicillium parvum. The structure of 1 was determined by interpretation of MS and homo- and heteronuclear 2D NMR spectroscopic data and confirmed by X-ray crystallography. The absolute configuration of 5 was determined via MPA ester derivatization.