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Papers by Animesh Patra

Research paper thumbnail of Biological Activity of Fluorescent Copper Complex: Synthesis, Crystal Structure, DFT and Protein Binding Study

Journal of Advanced Scientific Research

Synthesis of square planar copper (II) complex with formula [Cu (DMAP)2(NCS)2] (1) (DMAP =N,N-dim... more Synthesis of square planar copper (II) complex with formula [Cu (DMAP)2(NCS)2] (1) (DMAP =N,N-dimethyl-4 aminopyridine) was done and characterized by various spectroscopic and single-crystal X-ray diffraction study. Complex 1 crystallizes in the monoclinic space group, P 21/c, with cell dimensions a = 6.066(2), b = 10.702(4), c = 14.561(5) Å, a = 90 b = 93.11(2) and c = 90. The electron transfer mechanism of copper (II) complex was measured by cyclic voltammetry and indicate copper (II) complex is the Cu(II)/Cu(I) couple. The electronic structure and spectral properties of the complex-1 has been explained by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. In-vitro, human serum albumin (HSA) binding was also carried out using absorption and fluorescence technique, which showed considerable binding affinities of the complex with HSA. Again we report the synthesis of copper complex-HSA microcrystals. The complex has been screened for a...

Research paper thumbnail of Synthesis and characterization of Cadmium (II) complex with tetradentate N2O2- donor Schiff base and biological activity

International Journal of Scientific Research in Biological Sciences, 2019

Transition metal complex of Cd (II) with tetradentate schiff base derived from the condensation o... more Transition metal complex of Cd (II) with tetradentate schiff base derived from the condensation of 4-nitro-1,2diamino benzene and 5-nitro-salicyldehyde (H2L) have been synthesized. The synthesized square planar complex was investigated using elemental analysis (C, H and N), infrared, conductivity and electronic spectroscopic tools. The interactions of cadmium (II) complex examined towards Bovine serum albumin (BSA) with the help of absorption and fluorescence spectroscopic tools. The complex is strongly binds to proteins, then we study the antibacterial activity of the Schiff base and its cadmium complex by agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus).The result indicated that cadmium complex was more activity than ligand due to higher lipophilicity effect.

Research paper thumbnail of Manganese(II) coordination polymer having pyrazine and μ-phenolato bridging: Structure, magnetism and biological studies

Inorganica Chimica Acta, 2016

Abstract The manganese(II) coordination polymer, {[Mn(L)(pyz)]ClO4·2(H2O)}n. (1) has been synthes... more Abstract The manganese(II) coordination polymer, {[Mn(L)(pyz)]ClO4·2(H2O)}n. (1) has been synthesized from a mixture of Mn(ClO4)2·6H2O, Schiff base HL (derived from the condensation of 4-aminoantipyrine and salicylaldehyde) and pyrazine (pyz). Its molecular structure was determined by single crystal X-ray diffraction, which reveals that the polymeric structure consists of simultaneous Mn–Pyz–Mn and Mn–O(phenoate)–Mn bridges between the metal centers. Variable temperature magnetic studies give g = 2.037(4), J = −1.90(4) cm−1, ϑ = 0.5 K values, using a simple dinuclear Mn–Mn model, and indicates that the major exchange pathway is via the two phenoxide bridges and the pyrazine has little influence. The coordination polymer also shows enhanced antibacterial activity compared with the standard antibiotic levofloxacin.

Research paper thumbnail of Nickel(II) complexes of N2S2 donor set ligand and halide/pseudohalides: Synthesis, crystal structure, DNA and bovine/human serum albumin interaction

Journal of Chemical Sciences, 2015

A series of neutral hexacoordinated nickel(II) complexes of formula [Ni II (L)X 2 ] (where L = 3,... more A series of neutral hexacoordinated nickel(II) complexes of formula [Ni II (L)X 2 ] (where L = 3,4bis(2-pyridylmethylthio)toluene with tetradentate N 2 S 2 donor set and X = chloride (1), azide (2), cyanate (3) and isothiocyanate anion (4)) have been synthesized and isolated in pure form. The complexes were characterized by physicochemical and spectroscopic methods along with detailed structural characterization of 1,2 and 3 by single crystal X-ray diffraction analyses. The structural study showed that the nickel(II) ion has a distorted octahedral geometry being chelated by the tetradentate N 2 S 2 ligand and bound to cis-located choride or pseudohalide anions. In dimethylformamide solution the complexes showed quasi-reversible Ni II /Ni III redox couples in cyclic voltammograms with E 1/2 values of +0.723, +0.749, +0.768 and +0.868 V for 1, 2, 3 and 4, respectively. The study of interaction of the complexes with calf thymus DNA, bovine serum albumin (BSA) and human serum albumin (HSA) using spectroscopic and physicochemical tools clearly indicates that the complexes interact with DNA via groove binding mode.

Research paper thumbnail of Synthesis and Characterisation of Copper(II) Complexes with Tridentate NNO Functionalized Ligand: Density Function Theory Study, DNA Binding Mechanism, Optical Properties, and Biological Application

Bioinorganic Chemistry and Applications, 2014

The photo physical properties of two mononuclear pentacoordinated copper(II) complexes formulated... more The photo physical properties of two mononuclear pentacoordinated copper(II) complexes formulated as [Cu(L)(Cl)(H2O)] (1) and [Cu(L)(Br)(H2O)] (2)HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized and characterized by elemental, physicochemical, and spectroscopic methods. The density function theory calculations are used to investigate the electronic structures and the electronic properties of ligand and complex. The interactions of copper(II) complexes towards calf thymus DNA were examined with the help of absorption, viscosity, and fluorescence spectroscopic techniques at pH 7.40. All spectroscopy's result indicates that complexes show good binding activity to calf thymus DNA through groove binding. The optical absorption and fluorescence emission properties of microwires were characterized by fluorescence microscope. From a spectroscopic viewpoint, all compounds strongly emit green light in the solid state. The microscopy investigation suggested ...

Research paper thumbnail of Synthesis of biologically active cadmium (II) complex with tridentate N2O donor Schiff base: DFT study, binding mechanism of serum albumins (bovine, human) and fluorescent nanowires

Journal of Saudi Chemical Society, 2017

The photophysical properties of luminescent tetra-coordinated cadmium (II) complex formulated as ... more The photophysical properties of luminescent tetra-coordinated cadmium (II) complex formulated as [Cd(L)Cl],HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized and characterized by analytical and spectroscopic methods. The density function theory calculations are used to investigate the electronic structures of the ligand and its complex. The interactions of cadmium (II) complex towards bovine serum albumin (BSA) and human serum albumin (HSA) were investigated using absorption and fluorescence spectroscopic techniques at pH 7.4. The quenching constants, binding constants and number of binding sites were determined by fluorescence quenching method. The calculated thermodynamic parameters (DG, DH, and DS) confirmed that the binding reaction is mainly entropy-driven and hydrophobic forces played an important role in the reaction. Here, we proposed a new synthetic procedure for the preparation of BSA and HSA with cadmium complex nanowires. The scanning electron microscopy images show that BSA and HSA with cadmium complex product are wire-like in structure. The complex shows enhanced antibacterial activity compared with the free ligand and standard antibiotic chloramphenicol. Antioxidant studies showed that the complex has significant antioxidant activity against DPPH.

Research paper thumbnail of Nickel(II) complexes with 2-(pyridin-3-ylmethylsulfanyl)phenylamine and halide/pseudohalides: Synthesis, structural characterisation, interaction with CT-DNA and bovine serum albumin, and antibacterial activity

Polyhedron, 2013

ABSTRACT A new series of hexacoordinated octahedral nickel(II) complexes of 2-(pyridin-3-ylmethyl... more ABSTRACT A new series of hexacoordinated octahedral nickel(II) complexes of 2-(pyridin-3-ylmethylsulfanyl)phenylamine (L) formulated as [Ni(L)(4)(X)(2)] (1-4) [where X = Cl- (1); NCO- (2); N-3(-) (3) and NCS- (4)] has been synthesised and characterised by physicochemical, spectroscopic tools. Details of structural study of complex 1 using single crystal X-ray crystallography showed that distorted tetragonal environment around nickel(II) ion has been satisfied by four pyridinic-N donors of four organic moieties (L) and two chloride ions. All the complexes are redox active and the electrochemical study of the complexes showed only cathodic Ni-II/Ni-I redox couples in the range of -0.61 to -695 V versus Ag/AgCl. Interactions of 1 towards calf thymus-DNA by spectroscopic, viscosity-measurement and electrochemical study and towards bovine serum albumin (BSA) with the help of absorption and fluorescence spectroscopy were examined. Antibacterial activity of the complexes (1-4) studied by agar disc diffusion method showed the comparable inhibition activity of the nickel(II) complexes against some pathogenic bacteria namely Escherichia coli, Vibrio cholerae, Streptococcus pneumonia, Shigella sp. and Bacillus cereus.

Research paper thumbnail of Cyclometalated rhodium(III) complexes bearing dithiocarbamate derivative: Synthesis, characterization, interaction with DNA and biological study

Polyhedron, 2014

Abstract Reaction of three different dithiocarbamates (4-MePipzcdtH, L1H; MorphcdtH, L2H and 4-Bz... more Abstract Reaction of three different dithiocarbamates (4-MePipzcdtH, L1H; MorphcdtH, L2H and 4-BzPipercdtH, L3H) with [Rh(2-C6H4py)2Cl]2.1/4CH2Cl2 afforded a class of rhodium(III) complexes of the type [RhIII(2-C6H4py)2(L)]. The complexes were fully characterized by several spectroscopic tools along with a detailed structural characterization of [Rh(2-C6H4py)2(L1)] (1) by single crystal X-ray diffraction. Structural analysis of 1 showed a distorted octahedron in which both of the 2-phenylpyridyl nitrogens are in axial positions, trans to one another and the sulfur atoms are opposite to the phenyl rings. Electrochemical analysis by cyclic voltammetry reveals irreversible redox behavior of the rhodium centre in 1, 2 and 3. Their DNA binding ability have been also evaluated from the absorption spectral study as well as fluorescence quenching properties, suggesting the intercalative interaction of the complexes with CT-DNA due to the stacking between the aromatic chromophore and the base pairs of DNA. Antibacterial activity of complexes has also been studied by agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus).

Research paper thumbnail of Zinc(II) complexes of 1,3-bis(2-pyridylmethylthio)propane: Anion dependency, crystal structure and DNA binding study

Polyhedron, 2011

Zinc (II) complexes of the formula [Zn (L)(X) 2](where X= Cl−, N3−, NCO− and SCN−(1a–d, respectiv... more Zinc (II) complexes of the formula [Zn (L)(X) 2](where X= Cl−, N3−, NCO− and SCN−(1a–d, respectively)) and {[Zn (L)(ClO4)(H2O)](ClO4)} n (2), were isolated in the pure form on the reaction of 1, 3-bis (2-pyridylmethylthio) propane (L) with different zinc (II) salts. All the ...

Research paper thumbnail of Coordination behavior of symmetrical hexadentate O 2 N 2 S 2 -donor Schiff bases toward zinc (II): synthesis, characterization, and crystal structure

Journal of Coordination Chemistry, 2010

Two series of zinc(II) complexes of two Schiff bases (H2L1 and H2L2) formulated as [Zn(HL1/HL2)]C... more Two series of zinc(II) complexes of two Schiff bases (H2L1 and H2L2) formulated as [Zn(HL1/HL2)]ClO4 (1a and 1b) and [Zn(L1/L2)] (2a and 2b), where H2L1 = 1,8-bis(salicylideneamino )-3,6-dithiaoctane and H2L2 = 1,9-bis(salicylideneamino)-3,7-dithianonane, have been ...

Research paper thumbnail of Syntheses, crystal structures, and DNA-binding of some nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propane and pseudohalides

Journal of Coordination Chemistry, 2012

ABSTRACT A series of neutral octahedral nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propa... more ABSTRACT A series of neutral octahedral nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propane (L) and pseudohalide (X), formulated as [NiII(L)X2] (where X = azide (1), cyanate (2), and isothiocyanate (3)), was synthesized. The complexes were characterized by physico-chemical and spectroscopic methods, and 1 and 3 also by single-crystal X-ray diffraction analyses. The structural study shows nickel in a distorted octahedral geometry comprised of the tetradentate NSSN ligand with trans pyridines and monocoordinated pseudohalides in cis positions. In dimethylformamide solution, the complexes had quasi-reversible NiII/NiIII redox couples in cyclic voltammograms with E 1/2 values of +0.732, +0.747, and +0.815 V for 1, 2, and 3, respectively. To examine the biological activities of these complexes, interaction of 3 with calf thymus DNA was studied spectroscopically, showing groove-binding interaction.

Research paper thumbnail of Fluorescent copper(II) complexes: The electron transfer mechanism, interaction with bovine serum albumin (BSA) and antibacterial activity

Journal of Saudi Chemical Society, 2017

Dinuclear copper(II) complexes with formula [Cu 2 (L) 2 (N 3) 2 ] (1) and [Cu 2 (L) 2 (NCS) 2 ] (... more Dinuclear copper(II) complexes with formula [Cu 2 (L) 2 (N 3) 2 ] (1) and [Cu 2 (L) 2 (NCS) 2 ] (2) HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized by controlling the molar ratio of Cu(OAC) 2 AE6H 2 O, HL, sodium azide (1) and ammonium thiocyanate (2). The end on bridges appear exclusively in azide and thiocyanate to copper complexes. The electron transfer mechanism of copper(II) complexes is examined by cyclic voltammetry indicating copper(II) complexes are Cu(II)/Cu(I) couple. The interactions of copper(II) complexes towards bovine serum albumin (BSA) were examined with the help of absorption and fluorescence spectroscopic tools. We report a superficial solution-based route for the synthesis of micro crystals of copper complexes with BSA. The antibacterial activity of the Schiff base and its copper complexes were investigated by the agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus). It has been observed that the antibacterial activity of all complexes is higher than the ligand.

Research paper thumbnail of Biological Activity of Fluorescent Copper Complex: Synthesis, Crystal Structure, DFT and Protein Binding Study

Journal of Advanced Scientific Research

Synthesis of square planar copper (II) complex with formula [Cu (DMAP)2(NCS)2] (1) (DMAP =N,N-dim... more Synthesis of square planar copper (II) complex with formula [Cu (DMAP)2(NCS)2] (1) (DMAP =N,N-dimethyl-4 aminopyridine) was done and characterized by various spectroscopic and single-crystal X-ray diffraction study. Complex 1 crystallizes in the monoclinic space group, P 21/c, with cell dimensions a = 6.066(2), b = 10.702(4), c = 14.561(5) Å, a = 90 b = 93.11(2) and c = 90. The electron transfer mechanism of copper (II) complex was measured by cyclic voltammetry and indicate copper (II) complex is the Cu(II)/Cu(I) couple. The electronic structure and spectral properties of the complex-1 has been explained by density functional theory (DFT) and time dependent density functional theory (TDDFT) calculations. In-vitro, human serum albumin (HSA) binding was also carried out using absorption and fluorescence technique, which showed considerable binding affinities of the complex with HSA. Again we report the synthesis of copper complex-HSA microcrystals. The complex has been screened for a...

Research paper thumbnail of Synthesis and characterization of Cadmium (II) complex with tetradentate N2O2- donor Schiff base and biological activity

International Journal of Scientific Research in Biological Sciences, 2019

Transition metal complex of Cd (II) with tetradentate schiff base derived from the condensation o... more Transition metal complex of Cd (II) with tetradentate schiff base derived from the condensation of 4-nitro-1,2diamino benzene and 5-nitro-salicyldehyde (H2L) have been synthesized. The synthesized square planar complex was investigated using elemental analysis (C, H and N), infrared, conductivity and electronic spectroscopic tools. The interactions of cadmium (II) complex examined towards Bovine serum albumin (BSA) with the help of absorption and fluorescence spectroscopic tools. The complex is strongly binds to proteins, then we study the antibacterial activity of the Schiff base and its cadmium complex by agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus).The result indicated that cadmium complex was more activity than ligand due to higher lipophilicity effect.

Research paper thumbnail of Manganese(II) coordination polymer having pyrazine and μ-phenolato bridging: Structure, magnetism and biological studies

Inorganica Chimica Acta, 2016

Abstract The manganese(II) coordination polymer, {[Mn(L)(pyz)]ClO4·2(H2O)}n. (1) has been synthes... more Abstract The manganese(II) coordination polymer, {[Mn(L)(pyz)]ClO4·2(H2O)}n. (1) has been synthesized from a mixture of Mn(ClO4)2·6H2O, Schiff base HL (derived from the condensation of 4-aminoantipyrine and salicylaldehyde) and pyrazine (pyz). Its molecular structure was determined by single crystal X-ray diffraction, which reveals that the polymeric structure consists of simultaneous Mn–Pyz–Mn and Mn–O(phenoate)–Mn bridges between the metal centers. Variable temperature magnetic studies give g = 2.037(4), J = −1.90(4) cm−1, ϑ = 0.5 K values, using a simple dinuclear Mn–Mn model, and indicates that the major exchange pathway is via the two phenoxide bridges and the pyrazine has little influence. The coordination polymer also shows enhanced antibacterial activity compared with the standard antibiotic levofloxacin.

Research paper thumbnail of Nickel(II) complexes of N2S2 donor set ligand and halide/pseudohalides: Synthesis, crystal structure, DNA and bovine/human serum albumin interaction

Journal of Chemical Sciences, 2015

A series of neutral hexacoordinated nickel(II) complexes of formula [Ni II (L)X 2 ] (where L = 3,... more A series of neutral hexacoordinated nickel(II) complexes of formula [Ni II (L)X 2 ] (where L = 3,4bis(2-pyridylmethylthio)toluene with tetradentate N 2 S 2 donor set and X = chloride (1), azide (2), cyanate (3) and isothiocyanate anion (4)) have been synthesized and isolated in pure form. The complexes were characterized by physicochemical and spectroscopic methods along with detailed structural characterization of 1,2 and 3 by single crystal X-ray diffraction analyses. The structural study showed that the nickel(II) ion has a distorted octahedral geometry being chelated by the tetradentate N 2 S 2 ligand and bound to cis-located choride or pseudohalide anions. In dimethylformamide solution the complexes showed quasi-reversible Ni II /Ni III redox couples in cyclic voltammograms with E 1/2 values of +0.723, +0.749, +0.768 and +0.868 V for 1, 2, 3 and 4, respectively. The study of interaction of the complexes with calf thymus DNA, bovine serum albumin (BSA) and human serum albumin (HSA) using spectroscopic and physicochemical tools clearly indicates that the complexes interact with DNA via groove binding mode.

Research paper thumbnail of Synthesis and Characterisation of Copper(II) Complexes with Tridentate NNO Functionalized Ligand: Density Function Theory Study, DNA Binding Mechanism, Optical Properties, and Biological Application

Bioinorganic Chemistry and Applications, 2014

The photo physical properties of two mononuclear pentacoordinated copper(II) complexes formulated... more The photo physical properties of two mononuclear pentacoordinated copper(II) complexes formulated as [Cu(L)(Cl)(H2O)] (1) and [Cu(L)(Br)(H2O)] (2)HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized and characterized by elemental, physicochemical, and spectroscopic methods. The density function theory calculations are used to investigate the electronic structures and the electronic properties of ligand and complex. The interactions of copper(II) complexes towards calf thymus DNA were examined with the help of absorption, viscosity, and fluorescence spectroscopic techniques at pH 7.40. All spectroscopy's result indicates that complexes show good binding activity to calf thymus DNA through groove binding. The optical absorption and fluorescence emission properties of microwires were characterized by fluorescence microscope. From a spectroscopic viewpoint, all compounds strongly emit green light in the solid state. The microscopy investigation suggested ...

Research paper thumbnail of Synthesis of biologically active cadmium (II) complex with tridentate N2O donor Schiff base: DFT study, binding mechanism of serum albumins (bovine, human) and fluorescent nanowires

Journal of Saudi Chemical Society, 2017

The photophysical properties of luminescent tetra-coordinated cadmium (II) complex formulated as ... more The photophysical properties of luminescent tetra-coordinated cadmium (II) complex formulated as [Cd(L)Cl],HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized and characterized by analytical and spectroscopic methods. The density function theory calculations are used to investigate the electronic structures of the ligand and its complex. The interactions of cadmium (II) complex towards bovine serum albumin (BSA) and human serum albumin (HSA) were investigated using absorption and fluorescence spectroscopic techniques at pH 7.4. The quenching constants, binding constants and number of binding sites were determined by fluorescence quenching method. The calculated thermodynamic parameters (DG, DH, and DS) confirmed that the binding reaction is mainly entropy-driven and hydrophobic forces played an important role in the reaction. Here, we proposed a new synthetic procedure for the preparation of BSA and HSA with cadmium complex nanowires. The scanning electron microscopy images show that BSA and HSA with cadmium complex product are wire-like in structure. The complex shows enhanced antibacterial activity compared with the free ligand and standard antibiotic chloramphenicol. Antioxidant studies showed that the complex has significant antioxidant activity against DPPH.

Research paper thumbnail of Nickel(II) complexes with 2-(pyridin-3-ylmethylsulfanyl)phenylamine and halide/pseudohalides: Synthesis, structural characterisation, interaction with CT-DNA and bovine serum albumin, and antibacterial activity

Polyhedron, 2013

ABSTRACT A new series of hexacoordinated octahedral nickel(II) complexes of 2-(pyridin-3-ylmethyl... more ABSTRACT A new series of hexacoordinated octahedral nickel(II) complexes of 2-(pyridin-3-ylmethylsulfanyl)phenylamine (L) formulated as [Ni(L)(4)(X)(2)] (1-4) [where X = Cl- (1); NCO- (2); N-3(-) (3) and NCS- (4)] has been synthesised and characterised by physicochemical, spectroscopic tools. Details of structural study of complex 1 using single crystal X-ray crystallography showed that distorted tetragonal environment around nickel(II) ion has been satisfied by four pyridinic-N donors of four organic moieties (L) and two chloride ions. All the complexes are redox active and the electrochemical study of the complexes showed only cathodic Ni-II/Ni-I redox couples in the range of -0.61 to -695 V versus Ag/AgCl. Interactions of 1 towards calf thymus-DNA by spectroscopic, viscosity-measurement and electrochemical study and towards bovine serum albumin (BSA) with the help of absorption and fluorescence spectroscopy were examined. Antibacterial activity of the complexes (1-4) studied by agar disc diffusion method showed the comparable inhibition activity of the nickel(II) complexes against some pathogenic bacteria namely Escherichia coli, Vibrio cholerae, Streptococcus pneumonia, Shigella sp. and Bacillus cereus.

Research paper thumbnail of Cyclometalated rhodium(III) complexes bearing dithiocarbamate derivative: Synthesis, characterization, interaction with DNA and biological study

Polyhedron, 2014

Abstract Reaction of three different dithiocarbamates (4-MePipzcdtH, L1H; MorphcdtH, L2H and 4-Bz... more Abstract Reaction of three different dithiocarbamates (4-MePipzcdtH, L1H; MorphcdtH, L2H and 4-BzPipercdtH, L3H) with [Rh(2-C6H4py)2Cl]2.1/4CH2Cl2 afforded a class of rhodium(III) complexes of the type [RhIII(2-C6H4py)2(L)]. The complexes were fully characterized by several spectroscopic tools along with a detailed structural characterization of [Rh(2-C6H4py)2(L1)] (1) by single crystal X-ray diffraction. Structural analysis of 1 showed a distorted octahedron in which both of the 2-phenylpyridyl nitrogens are in axial positions, trans to one another and the sulfur atoms are opposite to the phenyl rings. Electrochemical analysis by cyclic voltammetry reveals irreversible redox behavior of the rhodium centre in 1, 2 and 3. Their DNA binding ability have been also evaluated from the absorption spectral study as well as fluorescence quenching properties, suggesting the intercalative interaction of the complexes with CT-DNA due to the stacking between the aromatic chromophore and the base pairs of DNA. Antibacterial activity of complexes has also been studied by agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus).

Research paper thumbnail of Zinc(II) complexes of 1,3-bis(2-pyridylmethylthio)propane: Anion dependency, crystal structure and DNA binding study

Polyhedron, 2011

Zinc (II) complexes of the formula [Zn (L)(X) 2](where X= Cl−, N3−, NCO− and SCN−(1a–d, respectiv... more Zinc (II) complexes of the formula [Zn (L)(X) 2](where X= Cl−, N3−, NCO− and SCN−(1a–d, respectively)) and {[Zn (L)(ClO4)(H2O)](ClO4)} n (2), were isolated in the pure form on the reaction of 1, 3-bis (2-pyridylmethylthio) propane (L) with different zinc (II) salts. All the ...

Research paper thumbnail of Coordination behavior of symmetrical hexadentate O 2 N 2 S 2 -donor Schiff bases toward zinc (II): synthesis, characterization, and crystal structure

Journal of Coordination Chemistry, 2010

Two series of zinc(II) complexes of two Schiff bases (H2L1 and H2L2) formulated as [Zn(HL1/HL2)]C... more Two series of zinc(II) complexes of two Schiff bases (H2L1 and H2L2) formulated as [Zn(HL1/HL2)]ClO4 (1a and 1b) and [Zn(L1/L2)] (2a and 2b), where H2L1 = 1,8-bis(salicylideneamino )-3,6-dithiaoctane and H2L2 = 1,9-bis(salicylideneamino)-3,7-dithianonane, have been ...

Research paper thumbnail of Syntheses, crystal structures, and DNA-binding of some nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propane and pseudohalides

Journal of Coordination Chemistry, 2012

ABSTRACT A series of neutral octahedral nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propa... more ABSTRACT A series of neutral octahedral nickel(II) complexes of 1,3-bis(2-pyridylmethylthio)propane (L) and pseudohalide (X), formulated as [NiII(L)X2] (where X = azide (1), cyanate (2), and isothiocyanate (3)), was synthesized. The complexes were characterized by physico-chemical and spectroscopic methods, and 1 and 3 also by single-crystal X-ray diffraction analyses. The structural study shows nickel in a distorted octahedral geometry comprised of the tetradentate NSSN ligand with trans pyridines and monocoordinated pseudohalides in cis positions. In dimethylformamide solution, the complexes had quasi-reversible NiII/NiIII redox couples in cyclic voltammograms with E 1/2 values of +0.732, +0.747, and +0.815 V for 1, 2, and 3, respectively. To examine the biological activities of these complexes, interaction of 3 with calf thymus DNA was studied spectroscopically, showing groove-binding interaction.

Research paper thumbnail of Fluorescent copper(II) complexes: The electron transfer mechanism, interaction with bovine serum albumin (BSA) and antibacterial activity

Journal of Saudi Chemical Society, 2017

Dinuclear copper(II) complexes with formula [Cu 2 (L) 2 (N 3) 2 ] (1) and [Cu 2 (L) 2 (NCS) 2 ] (... more Dinuclear copper(II) complexes with formula [Cu 2 (L) 2 (N 3) 2 ] (1) and [Cu 2 (L) 2 (NCS) 2 ] (2) HL = (1-[(3-methyl-pyridine-2-ylimino)-methyl]-naphthalen-2-ol) were synthesized by controlling the molar ratio of Cu(OAC) 2 AE6H 2 O, HL, sodium azide (1) and ammonium thiocyanate (2). The end on bridges appear exclusively in azide and thiocyanate to copper complexes. The electron transfer mechanism of copper(II) complexes is examined by cyclic voltammetry indicating copper(II) complexes are Cu(II)/Cu(I) couple. The interactions of copper(II) complexes towards bovine serum albumin (BSA) were examined with the help of absorption and fluorescence spectroscopic tools. We report a superficial solution-based route for the synthesis of micro crystals of copper complexes with BSA. The antibacterial activity of the Schiff base and its copper complexes were investigated by the agar disc diffusion method against some species of pathogenic bacteria (Escherichia coli, Vibrio cholerae, Streptococcus pneumonia and Bacillus cereus). It has been observed that the antibacterial activity of all complexes is higher than the ligand.