Synthesis of 2,4-Diaminoquinazoline and 2,4-Diaminopyrido-[2,3-d]pyrimidine Derivatives

In this work, several 2,4-diaminoquinazoline and 2,4-diaminopyrido[2,3-d]pyrimidine derivatives were designed and synthesized by acylation reaction and ring-closure reaction, using 6-chloro-5-cyanonicotinic acid, 3-cyano-4-fluorobenzoic acid, 4-cyano-3-fluorobenzoic acid and 6-chloro-5-cyanopicolinic acid as starting materials. This method is simple and efficient. For the used acids but 6-chloro-5-cyanopicolinic acid, the reaction yields are above 65%. The structures of terminational compounds were determined by H-1 NMR, C-13 NMR and LC-MS. The antitumor activities of the nitrogen mustard-linked chalcones were evaluated by an MTT assay. The results reveal that some of the title compounds exhibit potent anti-proliferative activities against selected tumor cells. Among which, compounds 4c, 4d, 4e and 4f against K562 and HepG2 were better than 5-fluorouracil.