Abstract
Dried mycelium of laboratory cultures of the type strain of Penicillium atrovenetum has yielded, by solvent extraction, about 15% of its weight of a complex mixture of crude coloring matters, from which about half this weight of a hitherto undescribed pigment, now named atrovenetin, has been isolated in a state of purity. Two other strains of P. atrovenetum also yield atrovenetin. Atrovenetin, C19H18O6, yellow-orange plates, m.p. 295[degree] (decomp.) is a dextrorotatory substance having characteristic color reactions. A number of functional derivatives and degradation products of atrovenetin are described. Atrovenetin is closely related structurally to the coloring matters, herqueinone and norherqueinone, of Penicillium herquei and is identical with deoxynorherqueinone. Atrovenetin, herqueinone and norherqueinone are believed to be derivatives of 9-hydroxyperinaphthen-1-one.