Antimicrobial azaphilones from the fungus Hypoxylon multiforme.

Four new azaphilones named multiformins A - D together with a known compound 4 : 5:4':5'-tetrahydroxy-1 : 1'-binaphthyl were isolated from the methanolic stromatal extract of the xylariaceous ascomycete Hypoxylon multiforme. Their absolute structures were characterised by 2D-NMR, UV, IR, mass and CD spectroscopy. Multiformins A - D showed strong and apparently non-selective antimicrobial activity.