Synthesis of Some Pyridothienopyrazolopyrimidopyrimidine and Mercaptomethylpyrazolopyrimidine Derivatives

Mercaptomethylpyrazolopyrimidine (2) was synthesized and reacted with ethyl chloroacetate to afford ethyl pyrazolpyrimidinylmethylmercapto acetate (3), which in turn was converted into the corresponding carbohydrazide 4. Carbohydrazide 4 reacts with a variety of reagents to give different pyrazolopyrimidines (5-12). Chloromethyl-pyrazolopyrimidine (1) reacts with chloropyridine to give compound 13, which was subjected in a series of reactions to give new compounds 14-20.