4-benzoyltetrahydro-2,3-furadione

ethyl 2-(3-methyl-2-oxocyclohexyl)-2-oxoacetate

N,1-dicyclohexyl-2,4,5-trioxopyrrolidine-3-carboxamide

多孔菌酸

methyl 7-(2,3,5-trioxocyclopentyl)heptanoate