ChemInform Abstract: Synthesis of Arylamino‐Substituted Pyrazolo[3,4‐d][1,2,4]triazolo[4,3‐a]pyrimidinones (IV), Pyrazolo[4,3‐e][1,2,4]triazolo[4,3‐a]pyrimidinones (VI), and Their Thermal Isomerization.

Abstract

Synthesis of Arylamino-Substituted Pyrazolo[3,4-d][1,2,4]triazolo[4,3-a]pyrimidinones (IV), Pyrazolo[4,3-e][1,2,4]triazolo[4,3-a]pyrimidinones (VI), and Their Thermal Isomerization. -Reaction of thiosemicarbazides (III) with Me-I/AcONagives regioselectively the linearly fused products (IV) while reaction of compounds (III) with DCC gives predominantly the angularly fused products (VI). Heating of these cyclization products above their melting products gives the rearrangement products (V). -(VAS'KEVICH*, R. I.; BENTYA, A. V.; STANINETS, V. I.; Russ.