Diaminopyrimidines (DAP) 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 piritreximhttp://aac.asm.org/cgi/content/full/45/12/3293 "Dicyclic and Tricyclic Diaminopyrimidine Derivatives as Potent Inhibitors of Cryptosporidium parvum Dihydrofolate Reductase: Structure-Activity and Structure-Selectivity Correlations" Nelson et al. 2001 and the antibiotics iclaprim and trimethoprim).
Some have been patented as anti-cancer drugs.
See also 2,4-Diaminopyrimidine 4,5-Diaminopyrimidine
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