Synthesis and characterization of new 1,3,4-thiadiazole derivatives: study of their antibacterial activity and CT-DNA binding.

1,3,4-Thiadiazole molecules (1-4) were synthesized by the reaction of phenylthiosemicarbazide and methoxy cinnamic acid molecules in the presence of phosphorus oxychloride, and characterized with UV, FT-IR, 13 C-NMR, and 1 H-NMR methods. DFT calculations (b3lyp/6-311++G(d,p)) were performed to investigate the structures' geometry and physiochemical properties. Their antibacterial activity was screened for various bacteria strains such as Enterobacter aerogenes , Escherichia coli ATCC 13048, Salmonella kentucky , Pseudomonas aeruginosa , Klebsiella pneumoniae , Proteus and Gram positive such as Staphylococcus aureus ATCC 25923, Listeria monocytogenes ATCC 7644, Enterococcus faecium , Enterococcus durans , Staphylococcus aureus ATCC, Serratia marcescens , Staphylococcus hominis , Staphylococcus epidermidis , alfa Streptococcus haemolyticus , Enterococcus faecium and found to have an inhibitory effect on Klebsiella pneumoniae and Staphylococcus hominis , while molecules 1, 3 and 4 had an inhibitory effect on Staphylococcus epidermidis and alpha Streptococcus haemolyticus . The experimental results were supported by the docking study using the Kinase ThiM from Klebsiella pneumoniae . All the investigated compounds showed an inhibitory effect for the Staphylococcus epidermidis protein. In addition, the mechanism of the 1-4 molecule interaction with calf thymus-DNA (CT-DNA) was investigated by UV-vis spectroscopic methods.