2-hydroxy-6,7-dimethoxy-3-(2-nitrophenyl)-1,4-naphthoquinone
2-hydroxy-6,7-dimethoxy-3-phenyl-[1,4]naphthoquinone
6,7-Dimethoxy-3-[1-(2-nitro-phenyl)-meth-(Z)-ylidene]-isochroman-1,4-dione
6,7-Dimethoxy-3-[1-phenyl-meth-(Z)-ylidene]-isochroman-1,4-dione
3-[1-(4,5-Dimethoxy-2-nitro-phenyl)-meth-(Z)-ylidene]-6,7-dimethoxy-isochroman-1,4-dione