Synthesis and condensation reactions of some new azole derivatives and investigation of antimicrobial activities

In the present study, first of all, 5-(pyridin-4-yl)-1,3,4-oxadiazol-2-thiol (35) was synthesised as reported in the literature and then converted to the corresponding 5-(pyridin-4-yl)-3-alkyl-1,3,4-oxadiazol-2(3H)-thion (95 and 96) by the treatment with suitable amines. The synthesis of 2-{[4-amino-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-yl]sulfanyl}-N'-(arilmethyliden)acetohidrazides (99-101) was performed starting from 4-amino-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-thiol (32) via the formation of ester (97) and hydrazide (98). Other type Schiff bases, 4-(arylmethylidenamino)-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-thiol (102-104) were obtained from the condensation between 32 and several aromatic aldehydes. The condensation of 4-phenyl-5-(pyridin-4-yl)-4H-1,2,4-triazol-3-thiol (28) with 3,4-dichloronitrobenzene in basic media afforded 4-{5-[(2-chloro-4-nitrophenyl)sulfanyl]-4-phenyl-4H-1,2,4-triazol-3-yl}pyridin (105). The reduction of two nitro groups of 105 to amino groups was performed by the treatment of 105 with hidrazin hydrate in the presence of Pd-C as catalyst. The structures of synthesized compounds were confirmed on the basis of spectroscopic techniques. New synthesis compounds were screened for their antimicrobial activities in the Rize University, department of Biology.