ethyl 2,6-dihydroxy-5-nitropyriMidine-4-carboxylate

ethyl 5-nitro-2,6-dioxo-3H-pyrimidine-4-carboxylate

Ethyl 5-nitroorotate, 2,6-Dioxo-4-(ethoxycarbonyl)-5-nitro-1,2,3,6-tetrahydropyrimidine