<b>Synthesis, characterization, antibacterial and antifungal studies of some transition and rare earth metal complexes of N-benzylidene-2-hydroxybenzohydrazide</b>

Abstract

The solid complexes of Cu(II), Co(II), Mn(II), La(III) and Ce(III) were prepared from bidentate Schiff base, N-benzylidene-2-hydroxybenzohydrazide. The Schiff base ligand was synthesized from 2hyhdroxybenzohydrazide and benzaldehyde. These metal complexes were characterized by molar conductivity, magnetic susceptibility, thermal analysis, X-ray diffraction, FTIR, 1 H-NMR, UV-Vis and mass spectroscopy. The analytical data of these metal complexes showed metal:ligand ratio of 1:2. The physico-chemical study supports the presence of square planar geometry around Cu(II) and octahedral geometry around Mn(II), Co(II), La(III) and Ce(III) ions. The IR spectral data reveal that the ligand behaves as bidentate with ON donor atom sequence towards central metal ion. The molar conductance values of metal complexes suggest their non-electrolyte nature. The X-ray diffraction data suggest monoclinic crystal system for these complexes. Thermal behavior (TG/DTA) and kinetic parameters calculated by Coats-Redfern method are suggestive of more ordered activated state in complex formation. The ligand and their metal complexes were screened for antibacterial activity against Staphylococcus aureus and Escherichia coli and fungicidal activity against Aspergillus niger and Trichoderma.

Synthesis, characterization and bioactivity ¬¬¬¬Zn2+, Cu2+, Ni2+, Co2+, Mn2+, Fe3+, Ru3+, VO2+ and UO22+ complexes of 2-hydroxy-5-((4-nitrophenyl)diazenyl)benzylidene)-2-(p-tolyl- amino)acetohydrazide

“…The  eff values showed that the (2-8) and (10)(11)(12) complexes are paramagnetic. The Cu 2+ complexes (2)(3)(4)(5) show  eff values in the 1.70-1.75 BM range which are compatible with one unpaired electron Cu 2+ in octahedral environmental [24]. Ni 2+ complex (6) shows  eff value 2.85 BM which is compatible with two unpaired electrons system of octahedral Ni 2+ complex [42].…”

“…Metal complexes, (3-4), (7)(8) and (10)(11)(12)(13) 2 with a suitable amount of a ligand ethanolic solution in molar ratio (1 metal : 2 ligand) in the presence of 2 mL of triethylamine. The reaction mixture was then refluxed for 3 hours.…”

“…The formed precipitates were filtered off, washed with ethanol, then with diethyl ether and dehydrated under vacuum over anhydrous CaCl 2 . The same method was used to prepare complexes; (2), (5-6) and (9) but in molar ratio (1 metal : 1 ligand) using the following salts; Cu(CH 3 COO) 2 …”

“…They have engaged significant interest to chemist and medical researchers for several decades, in order to their various biological and pharmaceutically implementations. hydrazone compounds and their transition metal complexes possess obvious biologically and pharmaceutically liveliness in medical chemistry, such as antimicrobial [1], antibacterial [2], antifungal [2], anticancer [3], antitumor [4], anticandidal [3], antitubercular [5], analgesic, anti-inflammatory [6], anticonvulsant [7], and leishmanicidal activities [8]. The derivatives N-2-(4-benzylpiperidinpiperazin-1-yl)acylhydrazone were tested in the treatment of Alzheimer diseases which have inhibition ability of acetylcholinesterase, butyryl cholinesterase and assemblage of amyloid beta peptides [9].…”

“…The derivatives N-2-(4-benzylpiperidinpiperazin-1-yl)acylhydrazone were tested in the treatment of Alzheimer diseases which have inhibition ability of acetylcholinesterase, butyryl cholinesterase and assemblage of amyloid beta peptides [9]. N-[(2,4-dihydroxyphenyl)methylidene]-2-(3,4-dimethyl-5,5-dioxidopyrazolo [4,3-c] [1,2]benzothiazin-1-(4H)-yl)acetohydrazide have anti-arthritic activity [10]. Cu 2+ , Co 2+ and Ni 2+ complexes N-[1-(pyridin-2-yl)ethylidene] acetohydrazide thiocyanato-bridged zig-zag polymers have inhibition effects on the outgrowth of human carcinoma cells of lung, hepatocellular and colorectal [11].…”