Selective Cyclization of 4-Amino-6-Metyl-3-Propargyl Mercapto-1,2,4-Triazin-5-One and 4-Amino-5-Metyl-3-Propargyl Mercapto-1,2,4-Triazol by a Green Hetropolyacid Catalyzed

3 Abstract: Cyclization of 4-amino-6-metyl-3-propargyl mercapto-1,2,4-triazin-5-one and 4-amino-5-metyl-3- propargyl mercapto-1,2,4-triazol derivatives 3 and 4 in the presence of Keggin heteropolyacids, H PW O , 3 12 40