C4H4N2O2 Urasil Pyrimidine-2,4(1H,3H)-dione 2-oxy-4-oxy pyrimidine

C4H4N2O2 
Urasil 
Pyrimiden-2(1H,3H)-dione 
2-oxy-4-oxy pyrimidene
Uracil Uracil-3D-vdW C5H5N5O Guanine C4H5N3O Cytosine C5H6N2O2 Thymine C5H5N5 Adenine Organic Chemistry