ANTIMICROBIAL TETRAHYDROANTHRAQUINONES FROM A STRAIN OF ALTERNARIA-SOLANI

Culture liquid and mycelia of a strain of Alternaria solani, which was isolated from a diseased Lycopersicon esculentum, afforded new tetrah ydroanthraquinones, altersolanols D, E and F, together with altersolan ols A, B and C. The structures of altersolanols D-F were shown to be t a,7-pentahydroxy-1,2,3,4-tetrahydroanthraquinone, eta,5-pentahydroxy-1 ,2,3,4-tetrahydroanthraquinone and ta,7-pentahydroxy-1,2,3,4-tetrahydr oanthraquinone, respectively, on the basis of chemical and spectroscop ic evidence. Altersolanols A-C and E showed antimicrobial activity aga inst Staphylococcus aureus, Bacillus subtilis, Micrococcus luteus and Pseudomonas aeruginosa, while altersolanols D and F did not show any a ctivity.