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Trifluoromethyl tetrazole was made according to the procedure published in Tetrahedron Letters 38(7):1257-1260. A mixture of tetrachlorosilane (5 mmol) and sodium azide (15 mmol) in dry acetonitrile (10 ml) and trifluoromethyl acetamide (5 mmol) was refluxed and stirred with the exclusion of moisture. The reaction mixture was poured into ice cold sodium carbonate solution and extracted with chloroform (3×20ml). The solvent was distilled off under reduced pressure to yield trifluoromethyl tetrazole (MS: MH—=136.7) which was used without further purification. Trifluromethyl tetrazole (1 mmol), Cs2CO3 (1.3 mmol) and 1-(2,4-dichlorophenyl)-2-chloroethan-1-one (1 mmol) were refluxed in DMF(2 ml) overnight. The reaction mixture was cooled and concentrated in vacuo, and then extracted into ethyl acetate and dried over sodium sulfate. The extract was further purified by column chromatography on silica gel to yield 1-(2,4-dichlorophenyl)-2-[5-(trifluoromethyl)(1,2,3,4-tetraazolyl)]ethan-1-one. 1 mmol of 1-(2,4-dichlorophenyl)-2-[5-(trifluoromethyl)(1,2,3,4-tetraazolyl)]ethan-1-one was heated to 80° C. in neat DMF-DMA for six hours. The reaction mixture was concentrated in vacuo and purified by trituration with diethyl ether. 1 mmol of the above enaminone, 1 mmol of amino {2-[(6-amino-5-nitro(2-pyridyl))amino]ethyl}carboxamidine hydrochloride and 3 mmol of Cs2CO3 were dissolved in DMF and heated to 90° C. for fourteen hours. The reaction mixture was concentrated in vacuo and extracted into ethyl acetate and the residue after solvent evaporation was purified by column chromatography eluting with 5-10% methanol in methylene chloride to yield {2-[(6-amino-5-nitro(2-pyridyl))amino]ethyl}{4-(2,4-dichlorophenyl)-5-[5-(trifluoromethyl)(1,2,3,4-tetraazolyl)]pyrimidin-2-yl}amine as a yellow powder after lyophilization.

1. customwas used without further purification
2. temperatureThe reaction mixture was cooled
3. concentrationconcentrated in vacuo
4. extractionextracted into ethyl acetate
5. dry with materialdried over sodium sulfate
6. customThe extract was further purified by column chromatography on silica gel