Because antimetabolite drugs structurally resemble DNA basepairs, they can become involved in processes associated withDNA base pairs—that is, the synthesis of nucleic acids and proteins.
Antimetabolites differ sufficiently from DNA base pairs in howthey interfere with this synthesis. Because the antimetabolites arecell cycle–specific and primarily affect cells that actively synthesize DNA, they’re referred to as S phase–specific. Normal cellsthat are reproducing actively, as well as the cancer cells, are affected by the antimetabolites.
These drugs are subclassified according to the metabolite affected and include:
· folic acid analogues
· pyrimidine analogues
· purine analogues.