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Co(II), Ni(II), Zn(II), and Cd(II) complexes were synthesized from a Schiff base ligand, benzyl-2-(1-(thiophen-2-yl)propylidene)hydrazine-1-carbodithioate (BTPHC), by conventional as well as microwave irradiation methods. The ligand and its metal complexes were characterized by spectroscopic techniques (FT-IR, UV-vis, mass spectrometry, and 1H NMR) and powder X-ray diffraction. Based on magnetic measurements and spectral data, octahedral environments for Co(II) and Ni(II) complexes and tetrahedral environments for Zn(II) and Cd(II) complexes are proposed. The metal(II) complexes were active toward bacterial and fungal strains. Antidiabetic studies showed that the Cd(II) complex possesses greater potential as an antidiabetic agent than the other metal complexes and the ligand. Antioxidant studies indicate that the Zn(II) and Cd(II) complexes possess high radical scavenging activities. The synthesized ligand and metal(II) complexes were screened for their anticancer properties against two human cancer cell lines MCF-7 and HeLa using an MTT cell viability assay. The Ni(II) complex excelled in halting the proliferation of HeLa and MCF-7 cancer cell lines with IC50 values of 46.63 µM and 80.90 µM, respectively, whereas it displayed insignificant cytotoxicity against the human normal embryonic kidney cell line (HEK293) with IC50 = 300.41 µM. [ABSTRACT FROM AUTHOR]

A new series of palladium(II) and platinum(II) Schiff base complexes have been synthesized by the interaction of ligands N-(2-fluoro benzylidene)isonicotinohydrazone (L¹H) and N-(2-fluorophenylethanone) isonicotinohydrazone (L²H) with PdCl2 and PtCl2. Elemental investigations, melting point determinations, molecular weight determinations, IR, ¹H NMR, and UV-Visible spectral studies were used to describe the structure and bonding pattern of ligands and their metal complexes. These analyses revealed that the ligands coordinate with the metal ions in a monobasic bidentate manner and that the complexes have a square planar geometry. The antimicrobial activities of both the ligands and their palladium(II) and platinum(II) complexes have been tested against various bacterial and fungal strains and showed considerable antifungal and antibacterial characteristics. The in vitro cytotoxic activity of [Pt(L2H)]Cl2 complex was assessed by examining its potential to inhibit cell proliferation against the human HeLa cell line(cervical cancer cell line) using MTT assay and the antioxidant activity of [Pt(L1H)2]Cl2 compound was performed against DPPH. The results showed a dose-dependent cytotoxic and radical scavenging activity thus pointing towards the biological significance of Pt(II) complexes. [ABSTRACT FROM AUTHOR]

This paper includes the synthesis of a Schiff base ligand and its palladium(II) complexes by conventional and green microwave-assisted techniques. They were characterized by conductivity measurements, mass spectrometry, FTIR, electronic spectroscopy, 1H NMR, and X-ray powder diffraction techniques. Based on analytical and spectral data, a square planar geometry was proposed for the metal complexes. The ligand(LH) and its metal complex[Pd(L)2] were screened for antimicrobial activity against pathogenic bacterial(Escherichia coli, Staphylococcus aureus) and fungal(Aspergillus niger, Penicillium chrysogenum) strains. Ciprofloxacin and Ketoconazole were used as standard drugs for antibacterial and antifungal activities respectively. The compounds showed moderate activity. The starting material(PdCl2), ligand(LH), and the metal complex [Pd(L)2] were screened for in vitro cytotoxic activity by MTT assay against cancerous cell lines (HeLa, MCF-7). Cisplatin was used as the standard drug. The metal complex, [Pd(L)2] was also screened for cytotoxic activity against normal cell line(HEK 293) to determine the selectivity index. The values of S.I(3.70-4.58) indicated that the complex [Pd(L)2] was more sensitive towards cancerous cell lines than normal cell line and may be studied further to assess its potential as cytotoxic agent. [ABSTRACT FROM AUTHOR]

A series of mononuclear organoantimony(III) and organoarsenic(III) complexes of bidentate Schiff base [2-(2- fluorophenyl)methylene]hydrazinecarbothioamide (LH) have been synthesized by the reaction of Ph3Sb and Ph3As with ligand in 1:1 and 1:2 molar ratios. All the synthesized compounds were characterized by elemental analyses, melting point determinations and a combination of electronic, IR, ¹H NMR, 13C NMR and X-ray diffraction studies. These studies have shown that the ligand coordinated to the antimony and arsenic in a monobasic bidentate manner through sulfur and nitrogen donor system. Thus, a tetra-coordinated and a penta-coordinated environment around the antimony and arsenic atom have been proposed for 1:1 and 1:2 complexes, respectively. All the complexes and parent ligand have been screened for their antimicrobial activity on several pathogenic fungi and bacteria and are found to possess appreciable fungicidal and bactericidal properties. Further, the ligand and its corresponding metal complexes have been tested for their DNA cleavage activity by the gel electrophoresis and the results revealed that the complexes are better cleaving agents than ligand. [ABSTRACT FROM AUTHOR]

New cytotoxic mononuclear Pt(II) coordination complexes of ligands {hydrazinecarboxamide (L1H) and hydrazinecarbothioamide (L2H) of 2-hydroxy-1-naphthaldehyde} have been synthesized. Free ligands, their metal complexes, and metal nanoparticles have been characterized based on elemental analysis, melting point, and molecular weight determinations, magnetic measurements, SEM, IR, 1H NMR, and UV–Visible spectra. Square planar geometry has been proposed to the complexes. The ligands and their complexes exhibit antimicrobial effects against various strains of bacteria and fungi. Platinum(II) nanoparticles were prepared by using green technique. The gel electrophoresis clearly exhibits that the metal complexes along with the ligands show cleavage activity on DNA of Escherichia coli (ATCC 25922). The newly synthesized complexes manifested significant in vitro cytotoxicity against human MCF-7 breast adenocarcinoma cancer cell line with cell death mainly caused by apoptosis. Further, nanoparticles of Pt complex exhibited MCF-7 cell multiplication through induction of apoptotic cell death. [ABSTRACT FROM AUTHOR]

A series of Zn(II) and Co(II) complexes have been synthesized by template condensation of bis(benzil)-4-chloro-1,2-phenylenediamine and bis(benzil)-4-fluoro-1,2-phenylenediamine, respectively, with 4-chloro-1,2-phenylenediamine and 4-fluoro-1,2-phenylenediamine in the presence of transition metal chlorides. The complexes have been characterized by physicochemical and spectroscopic techniques. Based on these studies, an octahedral geometry has been proposed around the metal ions. The newly synthesized ligands and their metal complexes have been screened for antimicrobial and anticancer activities. The in vitro cytotoxicity towards the HeLa cell line has been evaluated by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. [ABSTRACT FROM AUTHOR]

New Schiff bases 5-iodo-indol-2,3-dionehydrazinecarboxamide (L¹H) and 5-iodo-indol-2,3-dionehydrazinecarbothioamide (L²H) and their organotin(IV) complexes have been synthesized. The biologically potent ligands interacted with the Sn(IV) metal ion in 1:1 and 1:2 molar ratios, respectively, in dry methanol. Tentative structural conclusions of organotin(IV) complexes are described with the support of elemental analyses, melting points, and molecular weight determinations, infrared, nuclear magnetic resonance (¹H, 13C, and 119Sn), and ultraviolet-visible light spectroscopic studies. The spectroscopic data showed that the ligands are monobasic bidentate, coordinating through nitrogen and sulfur/oxygen atoms. Thus, suitable trigonal bipyramidal geometry and octahedral geometry have been suggested for the 1:1, and 1:2 metal complexes, respectively. The ligands and their complexes have been tested against various microbes for their in vitro antimicrobial activities. All complexes exhibit good antibacterial activity against the two bacterial species Escherichia coli and Staphylococcus aureus and remarkable antifungal activity against the two fungi Fusarium semitectum and Aspergillus flavus with respect to their corresponding ligands. The DNA cleavage efficiency of the ligands and the complexes has also been examined and discussed using gel electrophoresis technique, which showed the cleavage of DNA by all the metal complexes and ligands. [ABSTRACT FROM AUTHOR]

A new class of unsymmetrical palladium(II) macrocyclic complexes have been synthesized by template condensation reaction of the precursor, 2-[4-fluro-2-(2-oxo-1,2-diphenyl-ethylideneamino)-phenylimino]-1,2-diphenyl-ethanone (ML1) with appropriate diamines 1,2- diaminoethane, 1,3- diaminopropane, 1,4- diaminobutane, 1,5- diaminopentane and 1,6- diaminohexane, respectively in the presence of PdCl2.The reactions were carried out in 1:1:1 molar ratio. The precursor and its complexes have been characterized on the basis of elemental analyses, molecular weight determinations, conductance and magnetic susceptibility measurements and spectral studies including IR,1H-NMR,electronic,mass, spectra and X-ray powder diffraction studies.Based on analytical and spectral data, a four coordinated square planar geometry has been assigned for Pd(II) macrocyclic complexes. The redox properties of the complexes were extensively investigated by electrochemical method using cyclic voltammetry (CV). Thein vitroantimicrobial activity of Pd(II) macrocyclic complexes was studied and compared with that of free ligand. These complexes were also screened for their nematicidal and pesticidal activities. [ABSTRACT FROM AUTHOR]

The present study is structured to address the development of green microwave processes in the manufacture of a new series of biologically potent (N∧O) donor Schiff bases and their Cr(iii) complexes. These have been characterized by elemental analysis, melting point and molecular weight determinations, IR, UV-vis and EPR spectral analysis, and X-ray powder diffraction studies. The bioefficient compounds have been synthesized by thermal as well as microwave assisted methods. The azomethine ligands 1-(2-pyridyl) ethanone isonicotinoyl hydrazone (L1H) and 1-(2-naphthyl) ethanone isonicotinoyl hydrazone (L2H) have been synthesized by the condensation of 1-(2-pyridyl) ethanone and 1-(2-naphthyl) ethanone with isonicotinic acid hydrazide in a 1 : 1 molar ratio, using ethanol as a solvent. The Cr(iii) complexes have been prepared by mixing CrCl3·6H2O in 1 : 1 and 1 : 2 molar ratios with ligands L1H and L2H in methanol. The synthesized ligands and their new metal complexes have been screened in vitro for antimicrobial activity and in vivo for antifertility activity on male albino rats. The spectral data suggested a hexa-coordinated environment around the central metal ion. Physicochemical studies of the ligands and their Cr(iii) complexes aided the construction of their proposed structures. [ABSTRACT FROM AUTHOR]

A new series of Cr(III) macrocyclic complexes have been synthesized by template condensation of ligands 2-[4-chloro-2-(2-oxo-1,2-diphenyl-ethylideneamino)-phenylimino]-1,2-diphenyl-ethanone (ML1) and 2-[4-fluro-2-(2-oxo-1,2-diphenyl-ethylideneamino)-phenylimino]-1,2-diphenyl-ethanone (ML2) respectively, with appropriate diamines i.e. 1,2-phenylenediamine, 4- chloro 1,2-phenylenediamine and 4-fluro- 1,2-phenylenediamine in the presence of CrCl3.6H2O. The ligands and their complexes have been characterized on the basis of elemental analyses, molecular weight determinations, conductance and magnetic susceptibility measurements and spectral studies including IR, ESR, electronic spectra and X-ray powder diffraction studies. On the basis of these studies, a six-coordinated octahedral geometry has been proposed for all these complexes. The newly synthesized ligands and their complexes have been screened for their antimicrobial, nematicidal and pesticidal activities. The results are indeed positive. [ABSTRACT FROM AUTHOR]

Coordination and biocidal aspects of lanthanide(III) complexes with 3-formyl-4-chlorocoumarin hydrazinecarbothioamide (L1H) and 3-formyl-4-chlorocoumarin hydrazinecarboxamide (L2H) are described with the support of elemental analyses, molecular weight, melting point, and molar conductance determinations along with the IR, 1H NMR, EPR, UV spectral, and X-ray powder diffraction studies. The spectral data suggest that the ligands are monobasic bidentate, coordinating through nitrogen and sulfur/oxygen. The isolated products are colored solids, soluble in DMSO, DMF, and methanol. All the complexes are monomeric, as indicated by their molecular weight determinations. Conductivity measurements in dry DMF show them to be non-electrolytes. The antimicrobial, DNA cleavage, pesticidal, and nematicidal activities were examined and are discussed. [ABSTRACT FROM PUBLISHER]

The new ligands 3-(2-methyl-2,3-dihydro-benzthiazo-2-yl)-chromen-2one (AcBzH) and N′-[1-2-oxo-2H-chrome-3yl-ethylidene]-hydrazinecarbodithionic acid benzyl ester (AcBDTZH) were prepared by the reaction of 3-acetyl- 2H-chromen-2-one with 2-aminothiophenol and S-benzyl dithiocarbazate, respectively. The germanium(IV) complexes have been prepared by reacting Ph3GeCl and Me3GeCl in 1:1 molar ratio with these monofunctional bidentate AcBzH and AcBDTZH ligands by using microwave as well as conventional heating methods for comparison purposes. All the synthesized compounds were characterized by elemental analyses, melting point, IR, 1H-NMR 13C-NMR, mass and X-ray powder diffraction techniques. These studies showed that the ligands coordinated to the germanium atom in a monobasic bidentate manner and trigonal bipyramidal environment around the germanium atom have been established for the complexes. To evaluate the effect of metal ion upon chelation, both ligands and their complexes have been screened for their antimicrobial activity against the various pathogenic bacterial and fungal strains. The metal complexes have shown antimicrobial activity as compared to the free ligands. The pesticidal activity and DNA cleavage activity of both ligands and their metal complexes have been tested and discussed. [ABSTRACT FROM AUTHOR]

Microwave-assisted synthesis and spectroscopic studies of trimethyl and triphenyl germanium(IV) chelates derived from the reactions of organogermanium chlorides with the sodium salt of a biologically active nitrogen donor ligand are described. The resulting products have been isolated and characterized by elemental analyses, molecular weight determinations and conductance measurements, Systronics-Vadodara, India. On the basis of electronic, infrared, 1H and 13C NMR spectral studies, trigonal bipyramidal geometry has been suggested for the resulting complexes. The biologically active ligand and its corresponding complexes have been examined with regard to antifungal and antibacterial activity against pathogenic fungi and bacteria, and the results are rather encouraging. Both the compounds have also been found to act as nematicides by reducing the number of nematodes ( Meloidogyne incognita). [ABSTRACT FROM AUTHOR]

Heterocyclic ketimines, 1-(2-furanyl)ethanonehydrazincarbothioamide (L1H), 1-(2-furanyl)ethanone- hydrazincarboxamide (L2H), 1-(2-thienyl)ethanone hydrazincarbothioamide (L3H) and 1-(2-thienyl) ethanonehydrazincarboxamide (L4H), were prepared by the condensation of thiosemicarbazide and semicarbazide hydrochloride (in the presence of sodium acetate) in ethanol with the respective ketones by using microwave as well as conventional methods. Chromium(III) complexes have been prepared by mixing CrCl3·6H2O in 1:1 and 1:2 molar ratios with monobasic bidentate ketimines. The authenticity of the ligands and their complexes has been established by elemental analyses, melting point determinations, molecular weight determinations, EPR, infrared and UV spectral and X-ray powder diffraction studies. These studies showed that the ligands coordinated to the metal atom in a monobasic bidentate mode, coordinating through the nitrogen and sulfur/oxygen donor system. Thus, an octahedral environment around the metal atoms has been proposed. The growth-inhibiting potential of the ligands and complexes has been assessed against a variety of fungal and bacterial strains. [ABSTRACT FROM AUTHOR]

Two isoniazid Schiff bases, N-isonicotinamido-2-furanketimine (INH-F1) and N-isonicotinamido-5-methyl-2-furanketimine (INH-F2), possessing potential N and O coordination sites have been prepared by the reaction of isoniazid with 2-acetylfuran and 2-acetyl-5-methylfuran, respectively. Complexes of Pd(II) and Pt(II) have been prepared and characterized by elemental analyses, melting point determinations and electronic, infrared, 1H NMR, 13C NMR spectral studies, and X-ray powder diffraction studies. In all the complexes, the monobasic bidentate nature of the ligand is evident. Antibacterial and antifungal studies of these compounds against various pathogenic bacterial and fungal strains have been carried out. Both the ligands and their metal chelates were active against all the microbial strains investigated. However, the chelates were found to be more active than the ligands. The antimycobacterial activity of the ligands and their metal complexes has been evaluated against Mycobacterium smegmatis, which showed clear enhancement in this activity upon metal complexation with Schiff bases. [ABSTRACT FROM AUTHOR]

New chromium(III) complexes are synthesized by classical thermal and microwave (MW)-irradiated techniques. The Schiff bases 2-acetylfuran-S-benzyldithiocarbazate (L1H), 2-acetylthiophene-S-benzyldithiocarbazate (L2H), 2-acetylpyridine-S-benzyldithiocarbazate (L3H), and 2-acetylnaphthalene-S-benzyldithiocarbazate (L4H) were prepared by condensation of -S-benzyldithiocarbazate in ethanol with the respective ketones by using MW as well as conventional methods. The chromium(III) complexes have been prepared by mixing CrCl3 · 6H2O in 1 : 1 and 1 : 2 molar ratios with monofunctional bidentate ketimines. The structure of the ligands and their transition metal complexes were confirmed by elemental analysis, melting point determinations, molecular weight determinations, infrared (IR), electronic and electron paramagnetic resonance (EPR) spectral, and X-ray powder diffraction studies. On the basis of these studies it is clear that the ligands coordinated to the metal atom in a monobasic bidentate mode by S∩N donors. Thus, an octahedral environment around the chromium(III) has been proposed. The growth inhibiting potential of the ligands and complexes has been assessed against a variety of fungal and bacterial strains. [ABSTRACT FROM AUTHOR]

The synthetic, spectroscopic, and biological studies of some new palladium(II) and platinum(II) complexes derived from biologically active sulfur donor ligands 1H-indol-2,3-dione benzothiazoline (Bzt1H) and 5-nitro-1H-indol-2,3-dione benzothiazoline (Bzt2H) have been described. The reactions were carried out in 1:2 molar ratios. The authenticity of the benzothiazolines and their complexes has been established on the basis of elemental analyses; molecular weight determinations; and IR, 1H NMR, 13C NMR, and UV spectral studies. Based on IR and 1H NMR spectral studies, a square-planar structure has been assigned to these complexes. Studies were conducted to assess the comparative growth inhibiting potential of the synthesized complexes against the benzothiazolines for a variety of fungal and bacterial strains. The studies demonstrate that the ligands and complexes possess antimicrobial properties. Further, it was noted that the growth-inhibiting potential of the complexes is greater than the parent benzothiazolines. [ABSTRACT FROM AUTHOR]

Macrocyclic complexes of bivalent tin were synthesized by the template condensation method using benzildihydrazone with malonic, succinic, glutaric, adipic and phthalic acids. The reaction proceeded smoothly to completion. These macrocyclic complexes were characterized by elemental analyses, molecular weight determinations, infrared and 1H-NMR spectral analyses. The elemental analyses are consistent with the formation of complexes [Sn(Macn)Cl2] where n=1-5 and Mac represents a macrocyclic ligand moiety. All the complexes are stable in open atmosphere. The spectral studies confirmed the proposed framework of new macrocyclic complexes and indicated an octahedral geometry around the central metal atom. The complexes were screened in vitro against a number of pathogenic fungi and bacteria to assess their growth inhibiting potential. The antifertility activity is also discussed with positive findings. [ABSTRACT FROM AUTHOR]

The sulfur-nitrogen donor ligand, 1-acetylferrocenehydrazinecarbothioamide (L1H) and oxygen-nitrogen donor ligand, 1-acetylferrocenehydrazinecarboxamide (L2H) have been synthesized by condensation of 1-acetylferrocene with corresponding hydrazinecarbothioamide and hydrazinecarboxamide, respectively. The structure determination of palladium(II) and platinum(II) complexes was performed by elemental analysis, melting point determinations, conductivity measurements, molecular weight determinations, IR, 1H NMR and UV spectral studies. Based on these studies the square planar environment around the metal atoms has been proposed. Studies were also conducted to assess the comparative growth- inhibiting potential of the synthesized complexes and the azomethines against a variety of fungal and bacterial strains. [ABSTRACT FROM AUTHOR]

Hexacoordinated organotin and organosilicon derivatives have been prepared and characterized by analytical and spectroscopic techniques including UV, IR, 1H NMR, and 13C NMR spectra. The ligands used in the present account were derived by the condensation of thiosemicarbazide and 1H-Indol-2,3-dione, 1,3-dihydro-3-[2-(4-fluorophenyl)-2-oxo-ethylidene]-2H-indol-2-one, and 1,3-dihydro-3-[2-(4-fluoro-3-methyl-phenyl)-2-oxo-ethylidene]-2H-indol-2-one under microwave irradiation as well as by conventional heating. Newly synthesized complexes with their corresponding ligands were tested for their antifungal and antibacterial activities. The aim of the present study is to synthesize some novel ecofriendly fungicides and bactericides that have important pharmacodynamic significance. [ABSTRACT FROM AUTHOR]

Important properties of sulfur / oxygen and nitrogen bonded organoboron (III) complexes with biologically patent ligands vis., semicarbazone, thiosemicarbazone, and dithiocarbazone having the donor groups ONX and NS have been studied. The unimolar and bimolar reactions of phenylboronic acid with monobasic bidentate and dibasic tridentate ligands result in the formation of colored solids which have been characterized by the elemental analysis, molecular weight determinations, and conductance measurements. the UV, IR, and NMR (¹H, 13C, and 11B) spectral studies indicate tetracoordinated geometry for the resulting complexes. Both the ligands and their complexes have been screened for their fungicidal and bactericidal activities, and the results indicate that they exhibit significant antimicrobial properties. [ABSTRACT FROM AUTHOR]