Alternariol 9-O-methyl ether dimethyl sulfoxide monosolvate

R factor = 0.032; wR factor = 0.093; data-to-parameter ratio = 10.6. The title compound (systematic name: 3,7-dihydroxy-9-meth-oxy-1-methyl-6H-benzo[c]chromen-6-one dimethyl sulfoxide monosolvate), C15H12O5C2H6OS, was isolated from an unidentified endophytic fungus (belonging to class Ascomy-cetes) of Taxus sp. In the crystal, both the alternariol 9-O-methyl ether (AME) and the dimethyl sulfoxide (DMSO) molecules exhibit crystallographic mirror symmetry. One of the hydroxy groups makes bifurcated hydrogen bonds, viz. an intramolecular bond with the carbonyl group and an inter-molecular bond with the carbonyl group in an inversion-related AME molecule. In the crystal, the AME molecules are organized into stacks parallel with the b axis by – interactions between centrosymmetrically related molecules [the distance between the centroid of the central ring and the centroid of the methoxy-substituted benzene ring in the next molecule of the stack is 3.6184 (5) Å]. Pairs of DMSO molecules, linked via centrosymmetric C—H O contacts, are inserted into the voids created by the AME molecules, making O—H O and C—H O contacts with the hosts. Related literature For the bioactivity of AME and its precursor alternariol, see: Aly et al. (2008); Brugger et al. (2006); Pfeiffer et al. (2007); Miller et al. (2012). For their occurrence as contaminants in food and beverages, see: Lau et al. (2003). For the related crystal strucutre of alternariol, see: Dasari et al. (2012)