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161.
In vitro antimicrobial and antioxidant evaluation of rare earth metal Schiff base complexes derived from threonine
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Lekha Logu Kanmani Raja Kamatchi Hariharan Rajmohan Sathish Manohar Rajagopal Gurusamy Easwaramoorthi Deivanayagam 《应用有机金属化学》2015,29(2):90-95
Six novel Ln(III) Schiff base complexes were synthesized using rare earth metals with threonine and 5‐bromosalicylaldehyde, namely Pr(III), Sm(III), Gd(III), Tb(III), Er(III) and Yb(III) Schiff bases. These complexes were characterized using elemental analysis, molar conductivity, Fourier transform infrared and UV–visible spectroscopies, and thermogravimetry–differential thermal analysis. The general formula of the complexes is [Ln(L)(NO3)2(H2O)].NO3 (L = Schiff base ligand). The spectroscopic data reveal that the Schiff base ligand behaves as a tridentate ligand with ONO donor atoms sequencing towards the central metal ion. An investigation of fluorescence properties of the Sm(III), Er(III) and Tb(III) complexes shows that the Ln(III) ions can be sensitized efficiently by the ligand to some extent. Antimicrobial activity testing indicates that all six complexes exhibit antibacterial and antifungal ability against microbes with broad antimicrobial spectra. In addition, the antioxidant properties of the complexes were also screened. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
162.
S. Thangavelu 《Analysis Mathematica》1990,16(4):303-315
В РАБОтЕ пОлУЧЕНы УсИ лЕНИь РЕжУльтАтОВ МА РкЕттА О сУММИРУЕМОстИ МОДИФ ИцИРОВАННых РАжлОжЕНИИ лАгЕРРА. У стАНОВлЕНО, ЧтОα=1/6 Ест ь кРИтИЧЕскИИ ИНДЕкс Д ль сУММИРУЕМОстИ пО ЧЕжАРО. ДОкАжАНО, Чт О пРИα=1/6 сРЕДНИЕ ЧЕжАР О схОДьтсь пОЧтИ ВсУДУ. пОлУЧЕН тАкжЕ АНАлОг тЕОРЕМы ФЕИЕРА-лЕБЕгА. 相似文献
163.
Dhivyasundar Sundar Lakshmanan Karuppasamy Lakshmanan Gurusamy Cheng-Hua Liu Jerry J. Wu 《Current Opinion in Green and Sustainable Chemistry》2022
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164.
K. Subramanian P. Senthil Kumar P. Jeyapal N. Venkatesh 《European Polymer Journal》2005,41(4):853-861
A hitherto uninvestigated ligno-cellulosic seed fibre from the plant Wrightia Tinctoria has been chosen for the current study to unravel its physical properties, and potentialities in textile applications. Both raw and partially delignified fibres were tested for their morphological and structural features by X-ray diffraction, optical microscope and FT-IR spectra, thermal properties by thermogravimetry and differential scanning calorimetry and fibre fineness properties. The non-spinnable brittle virgin fibre becomes spinnable after partial delignification due to the decreased fibre rigidity imparted by lignin. Knitted fabrics were made successfully with (20%) and without cotton blending. 相似文献
165.
Complexes of 1-(3-hydroxy-2-naphthyl)-5-(p-X-phenyl)pent-4-ene-1, 3-diones (HXNP) (X = H, Cl, Me or OMe) with divalent metal ions, having the formula M(HXNP)2 (M = Cu, Ni or Co) and M(HXNP)2 · nB (n = 0,2: B = H2O or Py), have been prepared and characterized by elemental analyses, i.r., electronic, 1H-n.m.r. and e.s.r. spectroscopies and by magnetic susceptibility measurements. Spectral assignments show the metal ions to be coordinated through both carbonyl oxygen atoms and the effect of conjugation of the ligand structure (d–* interaction) is strong enough to stabilize the metal ligand bond. The observed hyperfine splitting constants and magnetic moments suggest that the copper complexes are monomers with a slightly distorted planar structure, having more covalent in plane -bonding. The magnetic and spectral properties of the dihydrates and dipyridinates of the cobalt and nickel complexes are commensurate with monomeric high-spin octahedral geometries; polymerization takes place on dehydration–depyridination of nickel(II) complexes. Oxovanadyl complexes of these -diketones have also been prepared; the ligand-to-metal ratio is 2:1 with square pyramidal geometry. The e.s.r. spectra of the complexes show the presence of one unpaired electron in the dxy orbital and the hyperfine splitting constants are sensitive to a change in solvent. The effect of bases on the redox behaviour of copper(II) complexes owing to geometry change is discussed. 相似文献
166.
167.
K.C. Kumara Swamy Sudha Kumaraswamy K. Senthil Kumar C. Muthiah 《Tetrahedron letters》2005,46(19):3347-3351
New α-aminophosphonates of the type (OCH2CMe2CH2O)P(O)CH(NHCO2R)(R′) [6a-i, 7a-e, and 8a-c] have been synthesized in high yields by a three-component reaction using (OCH2CMe2CH2O)PCl (3), benzamide (or urethane or benzyl carbamate), and an aldehyde without using any catalyst under solvent-free conditions. This route can be readily adapted for bis-aminophosphonates as well as optically active binaphthoxy α-aminophosphonates; it also tolerates the phenolic -OH group as shown by the synthesis of hydroxy functionalized aminophosphonates. Partial hydrolysis of compounds 7a-d leads to products in which the phosphorinane ring is cleaved first. Compounds (OCH2CMe2CH2O)P(O)CH[NHC(O)Ph](9-anthryl) (6f) and optically pure (R,S)-(−)-(C20H12O2)P(O)CH(NHCO2Et)(Ph) (14a) were characterized by X-ray crystallography. 相似文献
168.
Lellouche JP Perlman N Joseph A Govindaraji S Buzhansky L Yakir A Bruce I 《Chemical communications (Cambridge, England)》2004,(5):560-561
Magnetically responsive COOH-polydicarbazole-magnetite nanocomposites have been prepared by chemical oxidation of three COOH-dicarbazole monomers and - in the presence of magnetite nanoparticles. These functionalized nanoparticles have been tested for DNA hybridization experiments. 相似文献
169.
170.
Gurusamy Manivannan Pichai Maruthamuthu 《Journal of polymer science. Part A, Polymer chemistry》1986,24(12):3393-3398
The kinetics of polymerization of acrylonitrile initiated by peroxomonosulphate (PMS) has been carried out in the temperature range 45–60°C at constant ionic strength of 0.50 mol dm?3 under deaerated conditions. The rate of polymerization Rp has been investigated at various concentrations of monomer and initiator. The effects of [monomer], [initiator], [H+], ionic strength, temperature, and reducing agents (organic and inorganic substrates) on the rate of polymerization have been observed. Activation energy was found to be 15.2 kcal mol?1. 相似文献