Unusual bioactive 4-oxo-2-alkenoic fatty acids from Hygrophorus eburneus

Abstract

From fruit bodies of the basidiomycete Hygrophorus eburneus (Bull.: Fr.) Fr. (Tricholomataceae) eight fatty acids (C16, C18) with γ-oxocrotonate partial structure could be isolated. Initial tests demonstrate their bactericidal and fungicidal activity. The structures of (2E, 9E)-4-oxooctadeca-2,9,17-trienoic acid (1), (2E, 11Z)-4-oxooctadeca-2,11,17- trienoic acid (2), (E)-4-oxohexadeca-2,15-dienoic acid (3), (E)-4-oxooctadeca-2, 17-dienoic acid (4), (2E, 9E)-4-oxooctadeca-2,9-dienoic acid (5), (2E, 11Z)-4-oxooctadeca-2,11-dienoic acid (6), (E)-4-oxohexadec-2-enoic acid (7), and (E)-4-oxooctadec-2-enoic acid (8) were elucidated on the basis of their spectroscopic data.