Nickel(II) complexes of m-ethylphenylxanthate with nitrogen donors and their biological screening

1618-1626A series of five adducts of m-ethylphenylxanthate of nickel(II) [(m-C2H5C6H4OCS2)2Ni] with nitrogen donors have been synthesized in 1:2 molar ratio by the reaction of aqueous solution of NiCl2.6H2O with aqueous solution of sodium salt of m-ethylphenylxanthate. These metal complexes are reacted with nitrogen donors to give donor stabilized complex, [(m-C2H5C6H4OCS2)2(L)2Ni] where, L= 2-, 3-, 4-ethylpyridine and 2-, 3-chloropyridine. The adducts have been characterized by elemental analysis, molar conductance and magnetic susceptibility measurements, IR, electronic, mass spectral studies, thermogravimetric analysis, powder X-ray diffraction, biological studies. The spectral studies have revealed the octahedral coordination of ligands around Ni(II) metal ion. The adducts are found to be paramagnetic and non-ionic in nature. Mass studies show the monomeric nature of the adducts. The complexes have depicted potential antifungal activity against Bipolaris maydis and Rhizoctonia solani. Some of the synthesized Ni(II) xanthate complexes display in vitro cytotoxic efficacy against human cancer cell lines

Nickel(II) complexes of m-ethylphenylxanthate with nitrogen donors and their biological screening

A series of five adducts of m-ethylphenylxanthate of nickel(II) [(m-C2H5C6H4OCS2)2Ni] with nitrogen donors have been synthesized in 1:2 molar ratio by the reaction of aqueous solution of NiCl2.6H2O with aqueous solution of sodium salt of m-ethylphenylxanthate. These metal complexes are reacted with nitrogen donors to give donor stabilized complex, [(m-C2H5C6H4OCS2)2(L)2Ni] where, L= 2-, 3-, 4-ethylpyridine and 2-, 3-chloropyridine. The adducts have been characterized by elemental analysis, molar conductance and magnetic susceptibility measurements, IR, electronic, mass spectral studies, thermogravimetric analysis, powder X-ray diffraction, biological studies. The spectral studies have revealed the octahedral coordination of ligands around Ni(II) metal ion. The adducts are found to be paramagnetic and non-ionic in nature. Mass studies show the monomeric nature of the adducts. The complexes have depicted potential antifungal activity against Bipolaris maydis and Rhizoctonia solani. Some of the synthesized Ni(II) xanthate complexes display in vitro cytotoxic efficacy against human cancer cell lines

Synthesis and Spectroscopic and Biological Activities of Zn(II) Porphyrin with Oxygen Donors

Results of investigation of the physicochemical properties of zinc complexes containing substituted phenols as axial ligand having general formula [X-Zn-t(p-CH3) PP] [where X = different phenolates as axial ligand] in impurity-free organic solvent are presented. The four-coordinated zinc porphyrin accepts one axial ligand in 1 : 1 molar ratio to form five-coordinated complex, which is purified by column chromatography and characterized by physicochemical, biological evaluation and TGA/DTA studies. Absorption spectra show two principal effects: a red shift for phenols bearing substituted electron releasing groups (−CH3, −NH2) and blue shift for phenols bearing electron withdrawing groups (−NO2, −Cl) relative to Zn-t(p-CH3) PP, respectively. 1H NMR spectra show that the protons of the phenol ring axially attached to the central metal ion are merged with the protons of the porphyrin ring. Fluorescence spectra show two fluorescence peaks in the red region with emission ranging from 550 nm to 700 nm. IR spectra confirm the appearance of Zn-NPor and Zn-O vibrational frequencies, respectively. According to the thermal studies, the complexes have a higher thermal stability and the decomposition temperature of these complexes depends on the axial ligation. The respective complexes of X-ZnII-t(p-CH3) PP were found to possess higher antifungal activity (up to 90%) and higher in vitro cytotoxicity against human cancer cells lines

Synthesis and characterization of copper (II) and nickel(II) arylcarboxylate complexes with cyanopyridines

767-770The coper(II) and nickel(II) arylcarboxylates react with 2-, 3- and 4-cyanopyridines (CNPy) in an organic medium to give solid complexes having general formula [M(O2CR)2L] and [M(O2CR) 2L2]. R=<i style="mso-bidi-font-style: normal">o-CIC6H4- , o-<span style="mso-bidi-font-style: italic">OCH3 C<span style="mso-bidi-font-style: italic">6H4- and m-OCH<span style="mso-bidi-font-style: italic">3C6H4-; L=2-, 3- and 4-CNPy). All the complexes with Cu(II) arylcarboxylates are of 1:1 stoichiometry irrespective of the amount of ligand added and have been shown by physicochemical methods to be binuclear, containing bidentate bridging carboxylate group. Ni(II) arylcarboxylate complexes are mononuclear having bidentate chelating carboxylate group. Cyanopyridine moiety functions as a monodentate ligand coordinating through pyridine nitrogen atom. </span

Studies of cobalt (II) arylcarboxylates complexes with 3-and 4- cyanopyridines

291-294Cobalt (II) arylcarboxylates react with 3-and 4-cyanopyridines (CNPy) in ethanol to give solid complexes of the type [Co(O2CR) 2L] 2 (R=o- or m-<span style="font-size:14.0pt;font-family:Arial; mso-bidi-font-style:italic">Cl. C6<span style="font-size:14.0pt;font-family:HiddenHorzOCR; mso-bidi-font-family:HiddenHorzOCR">H4;  L = 3- or 4-CNPy) and [Co(O2CR) 2L] 2  (R= - C6<span style="font-size:14.0pt; font-family:HiddenHorzOCR;mso-bidi-font-family:HiddenHorzOCR">H5 p-<span style="font-size:14.0pt;font-family: Arial;mso-bidi-font-style:italic">CH3 C6<span style="font-size:14.0pt; font-family:HiddenHorzOCR;mso-bidi-font-family:HiddenHorzOCR">H4, o- or m-NO2 C6<span style="font-size:14.0pt; font-family:HiddenHorzOCR;mso-bidi-font-family:HiddenHorzOCR">H4 ; L=3- or 4-CNPy). The complexes have been characterized and are found to be binuclear with bidendate bridging carboxylate group and mononuclear octahedral species with bidentate chelating carboxylate groups respectively. Cyanopyridine moiety functions as a monodentate ligand coordinating through pyridine nitrogen atom.</span

Synthesis and bioactivity of oxovanadium(IV)tetra(4-methoxyphenyl)porphyrinsalicylates

Abstract Herein, we report the synthesis of metal complexes of vanadium with heterocyclic tetradentate ligand. Four N atoms of the heterocyclic porphyrin ring occupy the equatorial position and O atom of salicylic acid occupies the axial position in the complex. The thermal and chemical stability of the complexes were assessed by thermogravimetric analysis (TGA). The electrochemical behavior of the designed complexes is also studied using cyclic voltammetry. These complexes were then further evaluated for in vitro anticancer effects, anti-oxidant and behavior during acute toxicity of the synthesized porphyrin ligands and their oxovanadium(IV) complexes. The interaction of these metal complexes with radical scavenger 2,2-diphenyl-1-picrylhydrazyl (DPPH), encouraged us to study the anti-oxidant behavior of such complexes. The complex (SSA)VO(TMP) i.e. oxovanadium(IV)tetra(4-methoxyphenyl)porphyrinsulphosalicylate showed in vitro cytotoxic activity against glioblastoma (T986). It would be pertinent to mention here that the complex also did not exhibit any adverse toxicological symptoms and mortality in the target animal at the limit test dose level of 2000 mg/kg body weight

Synthesis and Spectroscopic Studies of Axially Ligated Zn(II)5,10,15,20-meso-tetra(p-chlorophenyl)porphyrin with Oxygen and Nitrogen Donors

Reaction of 5,10,15,20-meso-tetra(p-chlorophenyl)porphyrin[H2(p-Cl)pp] with zinc(II)acetate(Zn(OAc)2) and phenols results in the formation of corresponding axially ligated zinc(II)-meso-tetra(p-chlorophenyl)porphyrin (X-Zn-t(p-Cl)PP) (X = phenolates and pyridinates). The four-coordinated zinc porphyrin accepts one axial ligand in 1 : 1 molar ratio to form five-coordinated complex, which is purified by column chromatography and characterized by IR spectra, 1H NMR, electronic absorption spectra, elemental analysis, mass spectroscopy, and TGA/DTA studies. IR spectra confirms the appearance of Zn– at 500–400 cm−1, Zn– at 650–570 cm−1 and Zn–O at 650–350 cm−1. 1H NMR spectra show that the protons of the Phenolic ring axially attached to the central metal ion are merged with the protons of the tetraphenyl rings of the porphyrin moiety. Absorption spectra reveal that complexes are accompanied by blue shift (hypsochromic shift) for phenolates and red shift (bathchromic shift) for pyridinates in comparison with the basic Zporphyrin emission bands. Mass Spectra determine the m/z ratio. The percentage of each element is confirmed by elemental analysis. According to the thermal studies, the complexes have a higher thermal stability and the decomposition temperature of these complexes depends on the axial ligation. The invitro antifungal activity of the complexes synthesized above had been done by disc diffusion method against the pathogen “Fusarium spp.,” which shows that with the increase in the concentration of the complexes, the colony diameter decreases and hence percent inhibition increases

Electrochemical and Spectroscopic Characterization of Aluminium(III)-para-methyl-meso-tetraphenylporphyrin Complexes Containing Substituted Salicylates as Axial Ligands

A series of aluminium(III)-p-methyl-meso-tetraphenylporphyrin (p-CH3TPP-Al(III)) containing axially coordinated salicylate anion [p-CH3TPP-Al-X)], where X = salicylate (SA), 4-chlorosalicylate (4-CSA), 5-chlorosalicylate (5-CSA), 5-flourosalicylate (5-FSA), 4-aminosalicylate (4-ASA), 5-aminosalicylate (5-ASA), 5-nitrosalicylate (5-NSA), and 5-sulfosalicylate (5-SSA), have been synthesized and characterized by various spectroscopic techniques including ultraviolet-visible (UV-vis), infrared (IR) spectroscopy, proton nuclear magnetic resonance (1H NMR) spectroscopy, 13C NMR, and elemental analysis. A detailed study of electrochemistry of all the synthesized compounds has been done to compare their oxidation and reduction mechanisms and to explain the effect of axial coordination on their redox properties

Synthesis and spectroscopic studies of axially ligated aluminium(III)-p-methyl-meso-tetraphenylporphyrins

529-534Treatment of p-methyl-meso-tetraphenylporphyrin (p-CH3TPP) with aluminium(III) acetylacetonate (Al(acac)3) and phenol affords the corresponding axially ligated aluminium(III)-p-methyl-meso-tetraphenylporphyrin (Al(III)-p-CH3TPP). The separation and isolation of these derivatives have been achieved through chromatographic methods. The free base porphyrin and its axially ligated Al(III) derivatives are characterized by various spectroscopic techniques. 1H NMR spectra shows that the protons of the phenolic rings axially attached to the central metal ion are merged with the protons of the tetraphenyl ring of the porphyrin. The visible spectrum of axially ligated Al(III)p-methyl-meso-tetraphenylporphyrins show two bands, i.e., Q-bands. In axially ligated Al(III) derivatives, B and Q-bands exhibit a red shift on increasing the polarity of the solvent. The emission bands of axially ligated compounds are blue-shifted compared to free-base porphyrin but in the presence of an electron-accepting group axially attached to Al(III), the emission spectra is marginally red-shifted compared to other porphyrin compounds

Synthesis and Spectroscopic Characterization of Some New Axially Ligated Indium(III) Macrocyclic Complexes and Their Biological Activities

The synthesis and spectroscopic characterization of new axially ligated indium(III) porphyrin complexes were reported. Chloroindium(III) porphyrin (TPPIn-Cl) was obtained in good yield by treating the corresponding free base with indium trichloride. The action of the different phenols on chloroderivatives (TPPIn-Cl) led to the corresponding phenolato complexes (TPPIn-X). These derivatives were characterized on the basis of mass spectrometry, 1H-NMR, IR, and UV-visible data. The separation and isolation of these derivatives have been achieved through chromatography. The spectral properties of free base porphyrin and its corresponding metallated and axially ligated indium(III) porphyrin compounds were compared with each other. A detailed analysis of UV-Vis, 1H-NMR, and IR suggested the transformation from free base porphyrin to indium(III) porphyrin. Besides, 13C-NMR and fluorescence spectra were also reported and interpreted. The stability of these derivatives has also been studied through thermogravimetry. The complexes were also screened for anticancerous activities. Among all the complexes, 4-MePhO-InTPP shows highest anticancerous activity. The title complexe, TPPIn-X (where X = different phenolates), represents a five-coordinate indium(III) porphyrin complex in a square-pyramidal geometry with the phenolate anion as the axial ligand