ethyl 4-cyclopropyl-2,4-dioxobutanoate

N,N'-bis[2-(2-hydroxyethylamino)ethyl]oxamide

1-phenylheptane-1,3,4,6-tetrone

dimethyl 3,4-dihydroxyfuran-2,5-dicarboxylate

1,4-dihydrobenzo[g]quinoxaline-2,3-dione