Alternariol 9-O-methyl ether

Abstract

The title compound (AME; systematic name: 3,7-dihydroxy-9-methoxy-1-methyl-6H-benzo[c]chromen-6-one), C15H12O5, was isolated from an endophytic fungi Alternaria sp., from Catharanthus roseus (common name: Madagascar periwinkle). There is an intramolecular O—H...O hydrogen bond in the essentially planar molecule (r.m.s. deviation 0.02 Å). In the crystal, the molecule forms an O—H...O hydrogen bond with its centrosymmetric counterpart with four bridging interactions (two O—H...O and two C—H...O). The almost planar sheets of the dimeric units thus formed are stacked along b axis via C—H...π and π–π contacts [with C...C short contacts between aromatic moieties of 3.324 (3), 3.296 (3) and 3.374 (3) Å].