Preparation ,Characterization and The Biological Activity Study of A new heterocyclic (Azo-Schiff base) ligand and Their Complexation with {Co,Ni,Cu,Zn(II)}Ions

Abstract

A NEW tetra dentate Schiff base ligand has been synthesized from condensation of compound (1): [(4-((1-H-imidazol-2-yldiazenyl)-1,5-dimethyl-2-phenyl-1Hpyrazol-3(2H)-one)]with compound (2) thio semicarbazaide. The general formula of complexes are [M(L)]Cl 2 Where. M= Co(II) ,Ni (II)and Cu(II)Zn(II) are reported. The geometry structures of ligand and the complexes were determined through Fourier-transform infrared spectroscopy (FT-IR), Mass spectra, X-ray diffraction analysis, Ultra violet-Visible(UV-Vis), Proton nuclear magnetic resonance(1 H NMR) spectral studies, magnetic moment measurement, elemental analysis, and molar conductance. These studies revealed square planar geometries for Ni(II) and Co(II) and Cu(II)complexes, except the Zn(II) complex was a tetrahedral geometry around the central metal ion. Complex formation studies via molar ratio and continuous variation methods were consisted to those found in the solid complexes with a ratio of (M:L) as (1:1). Stability constant of complexes were calculated by spectrophotometric methods. Hyper Chem-8 program has been used to predict geometries structures of compounds in gas phase. The heat of formation (∆H f) and binding energy (∆E b) at 298 K for the metal complexes were calculated by PM 3 method. Biological activity studies of the ligand and their metal complexes against several organisms, bacteria Gram positive G(+ve)staphylococcus aureus and bacteria Gram negative G (-ve)Escherichia coli, klebsiella pneumonic, In addition to fungi like Aspergillus Niger, Rhizoclonia bataicola and Aspergillus flavus , are reported. Compounds exhibited the high activity on the growth of all types microorganisms in this study. This may be attributed to the impact of both the chelate effect of Schiff bases ligand and the role of the metal in these complexes.

Synthesis, Characterization, and X-ray Crystal Structure Analysis of Zinc(II) Complex Based on 2-benzimidazolethiole

“…In the IR spectrum of the ligand (2-BIT), the medium intensity peak at 3153 cm -1 can be related to the stretching vibration of the NH group which is shifted by 97 cm -1 to a higher frequency, is indicative of the formation of (N-H….O) intermolecular hydrogen bonding in the crystallized complex [17,18]. The absence of the stretching vibration of the thiol (SH) group at 2561 cm -1 in the IR spectrum of the complex, confirms that the thione tautomer to be more dominant over thiol Tautomer in the solid complex [19]. The broad medium intensity band for the complex at 3533 cm -1 could be assigned to the ν(O-H) vibration of the methanol molecule that crystallized in the complex [20].…”

Synthesis, Characterization, and Evaluation of Antioxidant and Physical Properties of New Bifunctional Aromatic Monomers Containing Imine and Heterocyclic Rings in The Main Chain.

“…The (C=C) aromatic appears at 1602 cm -1 while the (C-N) vibration absorption band appears at 1350 cm -1 , as noted in Figure 5. The FT-IR of P1C1 showed the disappearance of the imine absorption band at 1639 cm -1 and the appearance of new absorption bands at 1701 cm -1 and another at 1670 cm -1 referring to lactone(O-C=O) and lactam (N-C=O)formation of oxazepane monomer 28 . As oxazepane is a seven-membered heterocyclic compound with an aliphatic part, we notice an absorption band at 2933 cm -1 belongs to aliphatic (C-H) in addition to an aromatic (=C-H) at 3040 cm -1 with a (C=C) vibration at 1325 cm -1 and remaining of two (N-H) vibrations as seen in Figure 6.…”

Studies of spectroanalytical and the biological effectiveness of the Azo compound (J25) prepared from Ethyl p-aminobenzoate

“…used a series of pH value solutionś (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12) to study the acid and base effects of the solutions on the for (J25) [14] and Measure the ionization and protonization constants in the absorption range of 330-470 nm. The pH (2-12) values graphically represent the absorption spectrum of the (8x10-5) M solution of the prepared compounds (Figure 4).…”

“…The compound (J25) has a proton shape and an isopstic point at 385 nm. Its peak absorption is 360 nm in the pH range (4-8), 380 nm in the pH range (9)(10)(11), and 410 nm in the pH range (12). As shown in Figure 4, have drawn the pH absorption curves of the compound (J25) to document its ionisation and protonization constant (J25) at wavelength (360) nm.…”