Synonyms: 4aH-Xanthene-4a-carboxylicacid,7-(1,2,3,4,9,9a-hexahydro-4,8,9a-trihydroxy-3-methyl-9,11-dioxo-1,4a-(epoxymethano)-4aH-xanthen-7-yl)-2,3,4,9-tetrahydro-1,4,8-trihydroxy-3-methyl-9-oxo-,methyl ester, [1S-[1a,3b,4b,4aa,7(3R*,4R*,4aS*),9ab]]-; Ergochrysin B (7CI); 1,4a-(Epoxymethano)-4aH-xanthene,4aH-xanthene-4a-carboxylic acid deriv.; Ergochrome BC(2,2')