Synthesis and anti-TMV activity of 7-aralkyl-2-phenyl-3-(phthalimidomethyl/2-phenyl-3-ethyl-4-oxo-(3H) quinazolinyl)-1,3,4-thiadiazole [3,2-a]-s-triazine-5(6H, 7H)-thiones

Condensation of 2-amino-5-aralkyl-1,3,4-thiadiazole (1) with benzaldehyde in ethanol furnishes 5-aralkyl-2-benzylideno-imino-1,3,4-thiadiazoles (2). Reaction of (2) with ammonium thiocyanate in dioxan yields 7-aryalkyl-2-phenyl-1,3,4-thiadiazolo [3,2-a]-s-triazine-5-(6H, 7H) thiones (3). Interaction of (3) with N-hydroxy-methyl phthalimide/2-phenyl-3-hydroxy ethyl quinazolin-4-(3H) one results in the formation of 7-aralky-2-phenyl-3-phthalimido-methyl)/2-phenyl-3-ethyl-4-oxo (3H) quinazolinyl)-1,3,4-thiadiazolo [3,2a]-s-triazine-5-[6H, 7H]-thiones (4).