ethyl 2-(2,4-dioxo-1,3-oxazin-6-yl)acetate

6-(4-nitrophenyl)-1,3-oxazine-2,4-dione

1,3-二甲基-5,5-二苯基-2,4-咪唑烷二酮

1,3-二甲基-2,4,5,6(1H,3H)-嘧啶四酮 5-肟

4,5-二羟-1,3-二甲基-2-咪唑烷酮