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A series of Pd(II) and Pt(II) complexes with two N(∩)S donor ligands, 5-chloro-3-(indolin-2-one)benzothiazoline and 6-nitro-3-(indolin-2-one)benzothiazoline, have been synthesized by the reaction of metal chlorides (PdCl2 and PtCl2) with ligands in 1:2 molar ratios. All the synthesized compounds were characterized by elemental analyses, melting point determinations and a combination of electronic, IR, 1H NMR and 13C NMR spectroscopic techniques for structure elucidation. In order to evaluate the effect of metal ions upon chelation, both the ligands and their complexes have been screened for their antimicrobial activity against the various pathogenic bacterial and fungal strains. The metal complexes have shown to be more antimicrobial against the microbial species as compared to free ligands. One of the ligands, 5-chloro-3-(indolin-2-one)benzothiazoline and its corresponding palladium and platinum complexes have been tested for their antifertility activity in male albino rats. The marked reduction in sperm motility and density resulted in infertility by 62-90%. Significant alterations were found in biochemical parameters of reproductive organs in treated animals as compared to control group. It is concluded that all these effects may finally impair the fertility of male rats., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Reactions of 3-acetyl-2,5-dimethylthiophene with thiosemicarbazide and semicarbazide hydrochloride resulted in the formation of new heterocyclic ketimines, 3-acetyl-2,5-dimethylthiophene thiosemicarbazone (C(9)H(13)N(3)OS(2) or L(1)H) and 3-acetyl-2,5- dimethylthiophene semicarbazone (C(9)H(13)N(3)OS or L(2)H), respectively. The Pd(II) and Pt(II) complexes have been synthesized by mixing metal salts in 1:2 molar ratios with these ligands by using microwave as well as conventional heating method for comparison purposes. The authenticity of these ligands and their complexes has been established on the basis of elemental analysis, melting point determinations, molecular weight determinations, IR, (1)H NMR and UV spectral studies. These studies showed that the ligands coordinate to the metal atom in a monobasic bidentate manner and square planar environment around the metal atoms has been proposed to the complexes. Both the ligands and their complexes have been screened for their antimicrobial activities. The antiamoebic activity of both the ligands and their palladium compounds against the protozoan parasite Entamoeba histolytica has been tested., (Copyright 2009 Elsevier B.V. All rights reserved.)

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]

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]

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]

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]