5,5-dimethyl-2-(2-nitrobenzylidene)cyclohexane-1,3-dione

2-[(4,4-dimethyl-2,6-dioxocyclohexyl)-(2-nitrophenyl)methyl]-5,5-dimethylcyclohexane-1,3-dione

2-(2-acetylamino-α-hydroxy-benzyl)-5,5-dimethyl-cyclohexane-1,3-dione

3,3,6,6-tetramethyl-9-(2-nitrophenyl)-4,5,7,9-tetrahydro-2H-xanthene-1,8-dione