Synthesis and fungicidal activity of 3,6,9-triaryl-2-thioxothiazolo[4,5-d][1,3,4]oxadiazolo[2,3-b]pyrimidine and 3,10-diaryl-2-thioxothiazolo[4,5-d]-pyrimido [2,1-b] pyrimidines

Several 3,6,9-triaryl-2-thioxothiazolo[4,5-d][1,3,4]oxadiazolo[2,3-b] pyrim idines 4 and 3,10-diaryl-2-thioxodiazolo[4,5-d] pyrimido[2,1-b]pyrimidines 6 have been synthesised from the Michael adducts 3-aryl-5[{(5'-phenyl-1',3' ,4'-oxadiazol-2'-yl)amino}-(aryl)]-methyl-2-thioxo-4-thiazoiidinone 3 and 3 -aryl-5[(2-pyrimidylamino)aryl]methyl-2-thioxo-4-thiazolidinone 5, respecti vely which in turn have been prepared by the reaction of arylidenorhodanine s 2 with 2-amino-5-aryl-1,3,4-oxadiazoles and 2-amino pyrimidine, respectiv ely via Michael addition. The antifungal activity of the title compounds ha ve been screened against Aspergillus niger and Penicillium citrinum. The re sults have been compared with standard fungicide Carbendazim under similar conditions.