3,4-dihydroxy-1,2-epoxy-1,2,3,4-tetrahydrobenz(a)anthracene, (1aR-(1aalpha,2alpha,3beta,11calpha))-isomer
3,4-dihydroxy-1,2-epoxy-1,2,3,4-tetrahydrobenz(a)anthracene, (1ar-(1aalpha,2alpha,3beta,11calpha))-isomer