Browsing by Author "Animesh K. Ghose"

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Biamperometric Determination of Dysprosium and Samarium with 4-(2-Pyridylazo)resorcinol in the Presence of Octylphenolpoly(ethylene glycol) ether (Triton X-100)
(Indian Chemical Society, 1996) Devesh Srivastava; Animesh K. Ghose
The optimum conditions for the separation of Dy and Sm as PAR complexes in the micelles of Triton X-100 are described and a method for their biamperometric determination has been proposed. The determinations were carried out at pH 5.68 and 9.2 for Dy and Sm respectively.
Complexes of some trace metal ions with 5-fluorouracil
(1987) Udai P. Singh; Ranjana Ghose; Animesh K. Ghose
The preparation of 5-fluorouracil complexes with Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and Cd(II) are reported. The new complexes have been characterised by elemental analysis, solid-state infrared, electronic spectra and magnetic measurements. These measurements suggest that the ligand is bonded to the metal ions through the carbonyl group, behaving as a mono- dentate ligand. On the basis of the ν(OH)bending frequencies and the insolubility of the complexes in common organic solvents, polymeric structures have been proposed for the complexes, with bridging through OH groups. Mn(II), Zn(II) and Cd(II) form four-coordinated complexes, while six coordination numbers have been suggested for Co(II), Ni(II) and Cu(II). © 1987.
Crystal and Molecular Structure of 5‐Fluorocytosine‐Cobalt (II) Complex
(1992) Udai P. Singh; Animesh K. Ghose
[No abstract available]
Metal Ion Interactions with Nucleic Acid Base Pairs in Solution - A Potentiometric Study
(Indian Chemical Society, 1996) Sudha Singh; Animesh K. Ghose
The formation of bio-ligand chelates of some divalent transition metal ions, viz. MnII, CoII, NiII, CuII, ZnII and CdII with adenine as primary ligand (A) and 5-fluorouracil as the secondary ligand (L) has been carried out pH-metrically at 25° and at a constant ionic strength, μ = 0.1 M (NaNO3). The stability constants of binary MA and ternary MAL complexes, where M = MnII, CoII, NiII, CuII, ZnII and CdII, A = adenine and L = 5-fluorouracil, have been determined using a modified Irving-Rossotti technique and found to follow the Irving-Williams trend. In all the cases, CoII has minimum and CuII has maximum stability and all the mixed ligand complexes have been found to be less stable than the binary metal5-fluorouracil complexes except CnII and CdII, while it is more stable than metal-adenine binary complexes.
Simple and mixed complexes of cobalt(II) and cobalt(III) ions
(Kluwer Academic Publishers, 1988) Mandalika S. Sastry; Ranjana Ghose; Animesh K. Ghose
Bivalent and trivalent cobalt complexes with 1-(2-pyridylazo)-2-naphthol (PAN), PAN+1, 10-phenanthroline and PAN+2, 2′-bipyridyl were prepared and characterized by physico-chemical and magnetic measurements. The spectral studies suggest that PAN behaves as a bidentate ligand and is coordinated to metal ions through oxygen and (pyridine) nitrogen, whereas 1, 10-phenanthroline and 2, 2′-bipyridyl are coordinated through (pyridine) nitrogen. The tentative ν(M-O) and ν(M-N) band assignments in the lower i.r. region, and magnetic moment data favour four coordination for the complexes studied. © 1988 Chapman and Hall Ltd.
Synthesis and spectroscopic studies of simple and mixed complexes of nickel(ii)and zinc(ii)with an azo dye
(1994) Mandalika S. Sastry; Udai P. Singh; Animesh K. Ghose
New simple and mixed complexes of 1-(2-pyridylazo)-2-naphthol (PAN) and 1,10-phenanthroline (phen) or 2,2'-bipyridyl (bipy) with nickel(II) and zinc(II) were synthesized and characterized by elemental analyses, conductivity, infrared, electronic spectra, room temperature magnetic measurements, and X-ray diffraction studies. The I.R. data suggest the coordination of PAN through oxygen and (pyridine) nitrogen, whereas phen and bipy coordinate through the pyridine nitrogens. The UV-Vis. spectra along with magnetic measurements favor a tetrahedral geometry for the complexes. The podwer X-ray diffraction studies indicate tetragonal symmetry for all these complexes except for Ni(II)-PAN-phen, which has orthorhombic symmetry. © 1994, Taylor & Francis Group, LLC. All rights reserved.
Synthesis, characterization, and antitumor activity of 5-iodouracil complexes
(1991) Udai P. Singh; Badri N. Singh; Animesh K. Ghose; Rakesh K. Singh; Ajit Sodhi
Complexes of 5-iodouracil (5IU) with Mn(II), Co(II), Cu(II), Zn(II), and Cd(II) ions have been prepared, characterized, and subjected to a screening system for evaluation of antitumor activity against Sarcoma-180 (S-180) and L 929 tumor cells. The complexes were characterized by their elemental analysis, infrared spectra, electronic spectra, magnetic measurements, and powder x-ray diffraction. The antitumor activity results indicate that some complexes have good antitumor activity both in vivo and in vitro against S-180 and L 929 tumor cells. © 1991.
The effect of histidine on the structure and antitumor activity of metal-5-halouracil complexes
(1989) Udai P. Singh; Ranjana Ghose; Animesh K. Ghose; Ajit Sodhi; Sukh Mahendra Singh; Rakesh K. Singh
The ternary complexes of Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and Cd(II) ions with 5-halouracils, viz., 5-fluorouracil (SFU), 5-chlorouracil (5ClU), and 5-bromouracil (5BrU) and the biologically important ligand L-histidine (HISD) have been synthesized and characterized by elemental analysis, conductance measurements, infrared spectra, electronic spectra, and magnetic moment (room temperature) measurements. On the basis of these studies, the structures of the complexes have been proposed. All these ternary complexes were screened for their antitumor activity against Dalton's lymphoma in C3H/He mice. It was found that only Mn(II)-5BrU-HISD, Co(II)-5BrU-HISD, Cu(II)-SCIU-HISD Cu(II)-5BrU-HISD, Zn(II)-5FU-HISD, and Zn(II)-5BrU-HISD complexes have significant antitumor activity with T/C > 125 % (where T and C represent mean lifespan of treated mice and control mice respectively). The Mn(II)-5FU-HISD, Co(II)-5FU-HISD, Co(II)-5CIU-HISD, Ni(II)-5CIU-HISD, Ni(II)-5BrU-HISD, and Zn(II)-5CIU-HISD complexes are also effective antitumor agents, with T/C > 115 %. The complexes that showed effective antitumor action in vivo were also found to inhibit 3H-thymidine incorporation (DNA replication) in Dalton's lymphoma cells in vitro. © 1989.
Transition metal complexes of 5-chlorouracil
(Kluwer Academic Publishers, 1988) Udai P. Singh; Ranjana Ghose; Animesh K. Ghose
Complexes of 5-chlorouracil (5-ClU) (1) with 3d metal ions were characterized by elemental analysis, various spectroscopic methods (i.r., u.v. spectroscopy) and magnetic susceptibility measurements. The spectral evidence suggest that 5-ClU behaves as bidentate ligand in NiII, CuII, ZnII, and CdII compounds, coordinating through its one carbonyl oxygen and one nitrogen whereas with MnII and CoII it coordinates through the carbonyl oxygen only. The insolubility of the new complexes in organic solvents suggests that these are polymeric except for the CoII complex which is soluble in pyridine. There is probable OH bridging in the MnII and CuII complexes and the 5-ClU may bridge in the rest. © 1988 Chapman and Hall Ltd.
X‐ray diffraction studies on 5‐chlorouracil complexes with cobalt(II) and nickel (II)
(1989) Udai P. Singh; Ranjana Ghose; Animesh K. Ghose
[No abstract available]
X‐ray diffraction studies on metal complexes of 5‐nitrouracil
(1995) Udai P. Singh; Badri N. Singh; Mandalika S. Sastry; Animesh K. Ghose
[No abstract available]
X‐Ray Diffraction Studies on Oxovanadium (IV) Complex with 5‐Bromouracil
(1991) Udai P. Singh; Animesh K. Ghose
[No abstract available]