Department of Chemistry, Shibli National P.G. College, Azamgarh, UP (INDIA)

2-Bromo-6-methyl cyclohexanone on boiling with thiourea gave 2-amino-4-methyl-4,5,6,7-tetrahydrobenzothiazole (I), which inturn were treated with mixture of NH4SCN and aroyl halides in acetone followed by addition of 2-amino-5-phenyl-1,3,4-thiadiazole gives N1-aroyl-N3- (4,5,6,7)-tetrahydrobenzothiazole-2-yl-thioureas (IIa-j) compounds (IIa-j) further reacted with a mixture of POCl3 and PCl5 to yield 5-aryl-4,5,6,7- tetrahydrobenzothiazolo [3,2-a] [1,3,5]-triazine-3-thione (IIIa-j). Antifungal activity of the prepared compounds have been compared with Dithane M-45 against Puccinia recondita and Ustilagonuda var. maydis and the results correlated with their structural features.