The molecule is a naphthopyran that is 3,4-dihydro-naphtho[2,3-c]pyran-1-one which is sustituted by a 2-methoxy-2-oxoethyl group at position 3, a methoxy group at position 7, and hydroxy groups at positions 9 and 10 (the 3S enantiomer). It is produced by the fungus Paecilomyces variotii, isolated from the larvae of the mountain pine beetle Dendroctonus ponderosae. The biological precursor of viriditoxin. It has a role as a fungal metabolite. It is a heptaketide, a member of phenols, a methyl ester, a delta-lactone and a naphtho-alpha-pyrone.
methyl 2-[(3S)-9,10-dihydroxy-7-methoxy-1-oxo-3,4-dihydrobenzo[g]isochromen-3-yl]acetate