title: Structural, spectral, thermal and biological studies on (E)-2-(1-(4-hydroxyphenyl)ethylidene)-N-(pyridin-2-yl)hydrazinecarbothioamide and its metal complexes.
abstract: Schiff base complexes of Mn(II), Co(II), Ni(II), Cu(II), Cd(II), Hg(II) and U(VI)O2 with (E)-2-(1-(4-hydroxyphenyl)ethylidene)-N-(pyridin-2-yl)hydrazinecarbothioamide (H2PHAT) were synthesized and characterized by different physicochemical methods, elemental analysis, (UV-vis, IR and (1)H NMR spectra) and thermal analysis (TG and DTG) techniques. Spectral data showed that H2PHAT behaves as a NS bidentate ligand through both thione sulphur or thiol sulphur and the nitrogen of the pyridine ring or azomethine nitrogen, NSN tridentate ligand through both thione sulphur or thiol sulphur, the nitrogen of the pyridine ring and azomethine nitrogen. ESR spectrum data for Cu(II) solid complex confirms the square planar state is the most fitted one for the coordinated structure. The kinetic parameters were determined for each thermal degradation stage of the complexes using Coats-Redfern and Horowitz-Metzger methods. From modeling studies, the bond length, bond angle, HOMO, LUMO and dipole moment had been calculated to confirm the geometry of the ligand and their investigated complexes. The biological activity was tested against DNA showing that Cd(II), U(VI)O2, Ni(II) and Mn(II) complexes had powerful and complete degradation effect. Also, the ligand and its complexes were screened against Bacillus thuringiensis as Gram-positive bacteria and Pseudomonas aeuroginosa as Gram-negative bacteria using the inhibitory zone diameter.
authors.affiliation: Department of Toxic and Narcotic Drug, Forensic Medicine, Mansoura Laboratory, Medicolegal Organization, Ministry of Justice, Egypt.
authors.forename: T A
authors.initials: TA
authors.lastname: Yousef
authors.affiliation: Department of Chemistry, Faculty of Science, Mansoura University, Mansoura, Egypt. Electronic address: gaelreash@mans.edu.eg.
authors.forename: G M
authors.initials: GM
authors.lastname: Abu El-Reash
authors.affiliation: Department of Chemistry, Faculty of Arts and Science, Northern Border University, Saudi Arabia.
authors.forename: E R
authors.initials: ER
authors.lastname: El-Rakhawy
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D001419:Bacteria / Q000187:drug effects; D001424:Bacterial Infections / Q000188:drug therapy; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology; D004055:Differential Thermal Analysis; D006801:Humans; D019216:Metals, Heavy / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D008958:Models, Molecular; D013057:Spectrum Analysis; D013818:Thermogravimetry; D013882:Thiosemicarbazones / Q000138:chemical synthesis / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D056831:Coordination Complexes; D019216:Metals, Heavy; D013882:Thiosemicarbazones
keywords: Antibacterial; DNA; Molecular modelling; Thermal analysis; Thiosemicarbazone complexes