A One Step Synthesis of New 4-Aminopyrimidine Derivatives: Preparation of Tetrazolo- and s-Triazolopyrimidines

2-Mercapto-4-amino-5-cyano-6-arylpyrimidines (1a, b), 2-hydroxy derivatives 1c, d and 2-methylmercapto derivatives 4 a, b were synthesised via the reaction of either a mixture of malononitrile and aromatic aldehyde or arylidene malononitrile with thiourea, urea and S-methylisothiourea, respectively. 1c, d could also be obtained by the action of hydrogen peroxide on 1a, b or by the action of hydrochloric acid on 4a, b. Compounds 4a, b could also be prepared by the action of methyl iodide on 1a, b. 4a reacted with hydrazine hydrate to give the 2-hydrazino derivative 5 which condensed easily with aromatic aldehydes to give the Schiff’s bases 6 a, b. Compound 5 could be converted into the tetrazolo-and s-triazolopyrimidines 7 and 9 by the action of nitrous acid and carbon disulphide respectively. Structures of the newly synthesised compounds were established by chemical routes and spectral studies