Synthesis, Characterization, and Antimicrobial Evaluation of Thiadiazole Derivatives Derived from 2-Amino-5-Thio-1,3,4-Thiadiazole

This manuscript introduces a series of novel Schiff base and heterocyc-licring compounds, focusing on derivatives of 1,3-oxazepine and thiazo-lidinone.The derivative (2-Hydroxy-N-(5-mercapto-[1,3,4] thiadiazol-2-yl)-2-phenyl-acetamide was created by reacting ethyl mandelate ester[M1] and 2-amino-5-thio-1,3,4-thiadiazole compound to produce new compound [M2] and after that, compound [M2] was reacted with hydrazine hydrate 99% in dry DMF solvent, yielding the compound (N-(5-Hydrazino-[1,3,4]thiadiazol-2-yl)-2-hydroxy-2-phenyl-acetamide [M3]. In contrast , the Schiff base compound [M4] were synthesized by reacting compound [M3] with aromatic heterocyclic aldehyde (furan-2-carbaldehyde) in the presence of glacial acetic acid as a catalyst, and then Schiff base [M4] was reacted with maleic anhydride in dry benzene as a solvent to produce (1,3-Oxazepine) derivative [M5]. Additionally, the thiazolidinone derivative [M6] was synthesized through the reaction of equimolar amounts of (N-[5-(N'-Furan-2-yl-methylene-hydrazino)-[1,3,4]thiadiazol-2-yl]-2-hydroxy-2-phenyl-acetamide [M4] with thioacetic acid compound in chloroform as a solvent. The structural formula of all derivatives was confirmed by FT-IR and (1HNMR, 13CNMR) spectroscopy. The synthesized derivatives [M1-M6] were screened for their evaluated for antibacterial activity against S. aureus, S. epidermidis, E. coli, Klebsiella sp., and the fungus Candida albicans. Dimethyl sulfoxide (DMSO) was used as the solvent. Also, the ampicillin compound was used as the standard drug for comparison.