Abstract Regioselectivity was examined of reactions between nine 3 (5)-aminopyrazoles and 2-acetylcyclopentanone and 2-acetylcyclohexanone under various conditions. A series of cyclopenta [e] pyrazolo-[1, 5-a] pyrimidines was obtained. The highest regioselectivity of the reaction was observed in alcohol at 20° C in the presence of a catalytic quantity of trifl uoroacetic acid. The regiostructure of compounds was established by 1 H and 13 C NMR ...
