Abstract
Reduction of 5-phenyl-7-substituted aminofurazano (3, 4-d) pyrimidines with sodium borohydride was undertaken. In a sharp contrast with the cases of amino, alkylamino and tosylamino derivatives, the presence of acetyl group on the C7-amino function results in the smooth reduction of the amidine C=N bond to give 7-acetamido-6, 7-dihydro derivative. The presence of benzoyl group led to the formation of 6, 7-dihydro derivative accompanied with loss of benzamide. Analogously, reduction of 5-phenyl-7-ethylthiofurazano (3, 4-d) pyrimidine gave the 6, 7-dihydro derivative.
