All
 D03 Heterocyclic Compounds D006571 +
 D03.383 Heterocyclic Compounds, 1-Ring D006573 +
 D03.383.742 Pyrimidines D011743 +
 D03.383.742.698 Pyrimidinones D011744 +
 D03.383.742.698.875 Uracil D014498 +
 D03.383.742.698.875.237 Bromouracil D001976 
 D03.383.742.698.875.404 Fluorouracil D005472 +
 D03.383.742.698.875.480 Hydroxyphenylazouracil D006906 
 D03.383.742.698.875.660 Orotic Acid D009963 
 D03.383.742.698.875.700 Pentoxyl D010432 
 D03.383.742.698.875.842 Thiouracil D013889 +
 D03.383.742.698.875.899 Thymine D013941 
 D03.383.742.698.875.949 Uracil Mustard D014499