Metabolites of the Higher Fungi. Part 33. Grammicin, a novel bicyclic C7H6O4 furanoppyranol from the fungus Xylaria grammica (Mont) Fr.

Abstract

NoGrammicin 1 from Xylaria grammica is identified as 4-hydroxy-4H-furo[2,3-b]pyran-2(7aH)-one by chemical and physical methods. 4-Oxo-4H-pyran-3-acetic acid (¿-pyrone-3-acetic acid) 2 is a co-metabolite and the conversion of 1 into 2 is discussed