A simple and efficient method have been used for the synthesis of 3-Substituted derivatives of 4-Cyano-5-imino-3-methylthio-9-nitro-2H-1,2,4-triazipino [3,4-b] [1,3] benzothiazole have been prepared through one Step Multicomponent reaction by heating a mixture of 2-hydrazino-6-nitro benzothiazole (I) and bis methylthio methylene malononitrile (II) independently with aromatic amines / phenols / heterylamines / compounds containing active methylene group respectively in the presence of dimethyl formamide and catalytic amount of anhydrous potassium carbonate. All these newly synthesized compounds were screened for antifungal activity.