Synthesis, charecterization and biological evaluation of some 1, 3 and 4- Thiadiazoles schiff bases

Thiadiazoles and their analogues exhibit a wide variety of biological activities like antibacterial, antifungal, antitubercular, antidiabetic, anti-inflammatory, anti-convulsant, diuretic etc., In the present research work, some new series of 1,3,4- Thiadiazoles Schiffs bases were synthesized from Benzoic acid treated with thiosemicarbazide to form 2-amino-5-phenyl-1,3,4-thiadiazole derivative, the free amine group at the second position of the formed product was modified into various Schiffs bases by treating with different aromatic aldehydes to obtain the desired entity. The purity of the compounds was identified by TLC and purified by recrystallization and column chromatography. The structures were determined by IR, 1H NMR and Mass spectral data. 2-amino-5-phenyl-1, 3, 4-thiadiazole Schiff base analogues were screened for their antibacterial (Escherichia coli ATCC 25922), antifungal (Aspergillus niger ATCC 9029) by disc plate technique and antitubercular activity by use of MABA (Microplate Alamar Blue assay) analytical method on H37Rv strain of Mycobacterium tuberculosis. Based on the results shown by the synthesized compounds, all showed significant antimicrobial and antifungal activity activity. The mechanism of action of the compounds can be implicated for their cell wall disruption by inhibiting the peptidoglycon synthesis as potential antimicrobial agent or inhibiting the synthesis of mycolic acid as potential antitubercular agent.