Wiktionary
diaminopyrimidine
n. 1 (context organic compound English) Any of four isomeric diamino derivatives of pyrimidine 2 (context medicine English) Any of a class of drugs containing such a moiety
Wikipedia
Diaminopyrimidine
Diaminopyrimidines are a class of organic chemical compounds that include two amine groups on a pyrimidine ring.
They include many dihydrofolate reductase inhibitor drugs (such as pyrimethamine, trimetrexate, and piritrexim and the antibiotics Iclaprim and trimethoprim).
Some have been patented as anti-cancer drugs.