New Chlorine-Containing Depsidones From the Lichen Phyllopsora corallina var. ochroxantha

Abstract

The depsidones phyllopsorin (2-chloro-4,6-diformyl-3-hydroxy-8-methoxy- 1,9-dimethyl-11H-dibenzo[ b,e ][1,4]dioxepin-11-one (3), chlorophyllopsorin (2,7-dichloro-4,6-diformyl-3-hydroxy-8-methoxy-1,9- dimethyl-11H-dibenzo[ b,e ][1,4]dioxepin-11-one) (4), methyl 2,7- dichloro-psoromate (methyl 2,7-dichloro-4-formyl-3-hydroxy-8-methoxy- 1,9-dimethyl-11-oxo-11H-dibenzo[ b,e ][1,4]dioxepin-6-carboxylate) (5) and methyl 2,7-dichloronorpsoromate (methyl 2,7-dichloro-4-formyl-3,8- dihydroxy-1,9-dimethyl-11-oxo-11H-dibenzo[ b,e ][1,4]dioxepin-6-carb- oxylate ) (6) have been isolated from the lichen Phyllopsora corallina var. ochroxantha. The structures of these metabolites have been established from the spectroscopic properties, degradative studies and by partial synthesis.