Studies on biologically active heterocycles: Part X - Synthesis of 2-amino-4-[5-(2-chlorophenyl)-1,3,4-oxa/thiadiazol}-2-yl]-6-aryl/substibuted aryl-7-oxo-6,7-dihydrothiazolo[4,5-d]pyrimidine-5(H)-thiones as probable bioactive compounds

A series of new 2-amino-4-[5-{(2-chlorophenyl)-1,3,4-oxadiazolo}-2-yl]-6-ar yl/substituted-aryl-7-oxo-6,7-dihydrothia zolo[4,5-d]pyrimidine-5(H)-thione s 8a-h and 2-amino-4-[5-(2-chlorophenyl)-1,3,4-thiadiazol-2-yl]-6-aryl/subs tituted-aryl-7-oxo-6,7-dihydrothiazolo[4,5-d]pyrimidine5(H)-thiones 9a-h ha ve been synthesized from 3-[5-(2-chlorophenyl)-1,3,4-oxa/thiadiazol-2-yl]-1 -aryl/substituted-arylthiobarbituric acid 6, 7 which in turn are prepared f rom N-aryl/substituted-aryl, N-5-[(2-chlorophenyl)-1,3,4-oxa/thiadiazol-2-y l]thioureas 4, 5 on treatment with malonic acid, acetyl chloride and thiour ea respectively in the presence of chlorine. All the newly synthesized comp ounds have been characterized by their elemental analysis, physical and spe ctroscopic data. These substituted oxa/thiadiazolthiones are screened for t heir fungitoxic and antibacterial properties.