Mukesh Kumar Biyala

Coordination behavior and biopotency of N and S/O donor ligands with their palladium(II) and platinum(II) complexes

Some metal complexes of Schiff bases have been prepared by the interactions of palladium(II) and platinum(II) chloride with 5-chloro-1,3-dihydro-3-[2-(phenyl)-ethylidene]-2H-indol-2-one-hydrazinecarbothioamide(L1H) and 5-chloro-1,3-dihydro-3-[2-(phenyl)-ethylidene]-2H-indol-2-one-hydrazinecarboxamide(L2H), in bimolar ratios. All the new compounds have been characterized by elemental analyses, conductance measurements, molecular weight determinations, IR and 1H NMR spectral studies. The spectral data are consistent with a square planar geometry around Pd(II) and Pt(II) in which the ligands act as neutral bidentate and monobasic bidentate ligands, coordinating through the nitrogen and sulfur/oxygen atoms. Free ligands and their metal complexes were screened for their antimicrobial activity on different species of pathogenic fungi and bacteria and their biopotency has been discussed.

Structural studies with antimicrobial and antifertility activity of a monofunctional bidentate ligand with its boron(III), palladium(II), and platinum(II) complexes

The reaction of the sulfur donor Schiff base ligand, 7-nitro-3-(indolin-2-one) hydrazinecarbo-thioamide, with phenyldihydroxyboron in benzene, palladium(II)chloride, and platinum(II) chloride, in ethanol, gave the mononuclear tetracoordinated and hexacoordinated complexes. The Schiff base ligand coordinated to the boron atom in 1:1 and 1:2 molar ratios and to the palladium and platinum metals in only 1:2 molar ratios in the presence of an acidic and basic medium. Tentative structural conclusions are drawn for reaction products based upon elemental analysis, electrical conductance, and spectral (electronic, infrared, 1 H NMR, 13 C NMR, and 11 B NMR) data. The antifertility activity of the ligand and its nonmetal/metal complexes are discussed with a comparative study in an effective manner.

Important Properties of Sulfur–Bonded Organoboron (III) Complexes with Biologically Potent Ligands

Abstract Important properties of sulfur/oxygen and nitrogen bonded organoboron (III) complexes with biologically potent ligands viz., semicarbazone, thiosemicarbazone, and dithiocarbazate 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 ( 1 H, 13 C, and 11 B) 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.

Coordination chemistry of palladium(II) and platinum(II) complexes with bioactive Schiff bases: Synthetic, spectral, and biocidal aspects

The Schiff bases, 5-nitro-indol-2,3-dionehydrazinecarboxamide (HSCZ1) and 7-nitro-indol-2,3- dionehydrazinecarboxamide (HSCZ2), have been synthesized by the condensation of 5-nitro-indol-2,3-dione and 7-nitro-1H-indol-2,3-dione with semicarbazide hydrochloride, respectively. The palladium(II) and platinum( II) complexes have been prepared by mixing palladium chloride and platinum chloride in 1: 2 molar ratios with monobasic bidentate Schiff bases. The ligands and complexes of palladium and platinum have been characterized by elemental analyses, melting point determinations, conductance measurements, molecular weight determinations, and IR, 1H NMR, and UV spectral studies. These studies showed that the ligands coordinate to the metal atoms in a monobasic bidentate mode, coordinating through oxygen and nitrogen donor systems. Thus, a tetracoordinated environment around the metal atom has been proposed. Both the ligands and their complexes have been screened for their biological activity on several pathogenic fungi and bacteria and were found to possess appreciable fungicidal and bactericidal properties. Plant growth regulating activity of one of the ligands and its complexes has also been recorded on gram plant, and results have been discussed.

Biologically Potent Azomethine Complexes of Palladium(II) and Platinum(II)

The sulfur-nitrogen donor ligand, 1-acetylferrocenehydrazinecarbothioamide (L 1 H) and oxygen-nitrogen donor ligand, 1-acetylferrocenehydrazinecarboxamide (L 2 H) 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, 1 H 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.