Synthesis of 1,2,4-triazolo and thiadiazolo [3, 2-b]-1,3,4,-oxadiazoles with 6-thiones as possible antifungal agents.
Dept. of Chemistry, University of Gorakhpur, Gorakhpur-273009
A R Misra Dept. of Chemistry, University of Gorakhpur, Gorakhpur-273009
Several 2-aryl-5-phenyl (or unsubstituted)-1,2,4,-triazolo [3,2-b]-1,3,4-oxidiazolo-6-thiones (IIIa-f) and 2- aryl-6-phenyl-imino (or imino)-1,2,4-thiadiazolo [3, 2-b]-1 ,3, 4-oxadiazoles (IVa-f) were readily synthesized by oxidation cyclization of corresponding N-phenyl-N'-(5-aryl-1, 3, 4- oxadiazol-2-yl) thioureas (IIId-f) and N'-(5-aryl-1,3,4-oxadiazol-2-yl) thioureas (III-c) with SOCI2/pyridine and I2/EtOH. The required thioureas (IIIa-f) were prepared by reacting 2-aminooxadiazoles (Ia-c) either by Ar-N = C=S or KSCN. Twelve such compounds have been synthesised and fungitoxicity in vitro determined against Aspergillus niger and Fusarium oxysporium. Standard commercial fungicide Dithane M-45 was also tested under similar conditions for comparing the results,and results have been correlated with the structure feature of the tested compounds.