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71.
Seema Pant Priyanka Sharma Umesh C. Pant 《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2974-2983
Six 5-substituted-2-aminobenzenethiols have been reacted with 3-(2-chlorophenyl)-1-(4-chlorophenyl)-2-propenone and 3-(2-chlorophenyl)-1-(2-thienyl)-2-propenone in dry ethanol saturated with dry HCl gas, to obtain twelve new compounds, 8-substituted-2-(2-chlorophenyl)-4-(4-chlorophenyl/2-thienyl)-2,5-dihydro-1,5-benzothiazepines in satisfactory yields. The structures of the final products have been assigned by elemental microanalyses data for elements, C, H, and N and by IR, 1 H NMR, and mass spectroscopies. The synthesized compounds have been evaluated for their relative antimicrobial activity against the gram-positive bacteria, Staphylococcus aureus, gram-negative bacteria, Pseudomonas aeruginosa and the fungus, Candida albicans. The compounds have been found to show little antibacterial activity, but interestingly, showed significant antifungal activity. 相似文献
72.
A “One Pot,” Environmentally Friendly,Multicomponent Synthesis of 2‐Amino‐5‐cyano‐4‐[(2‐aryl)‐1H‐indol‐3‐yl]‐6‐hydroxypyrimidines and Their Antimicrobial Activity 下载免费PDF全文
Ragini Gupta Anshu Jain Yogita Madan Ekta Menghani 《Journal of heterocyclic chemistry》2014,51(5):1395-1403
A series of multifunctional 2‐amino‐5‐cyano‐4‐[(2‐aryl)‐1H‐indol‐3‐yl]‐6‐hydroxypyrimidines ( 4a , 4b , 4c , 4d , 4e , 4f ) was synthesized by multicomponent reaction of 3‐formylindole ( 1 ), cyanoethylacetate ( 2 ), and guanidine hydrochloride ( 3 ) with NaOH by using green chemical techniques, viz. microwave irradiation and grindstone technology. The same reactants when refluxed in ethanol also gave titled compounds ( 4a , 4b , 4c , 4d , 4e , 4f ). Compared with conventional procedure, the reaction can be carried out under milder conditions, requiring a shorter reaction time and giving higher yields following the green chemistry methodology. All the synthesized compounds have been characterized on the basis of elemental analyses and spectral data (IR, 1H NMR, 13C NMR, and mass). All synthesized compounds were also evaluated for their antimicrobial activity against nine pathogenic bacteria, antifungal activity against Rhizopus stolonifer, Aspergillus flavus, and Fusarium oxysporum and antibacterial activity against Escherichia coli and Pseudomonas aeruginosa at different concentrations. Most of the compounds showed mild to moderate activity. 相似文献
73.
T. Rajeshwari S. Rajesh B. R. Kerur S. Anilkumar Narayani Krishnan Amar D. Pant 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):61-65
The activity of the terrestrial primordial radionuclides 226Ra, 232Th and 40K are measured for Bidar soil samples. The collected soil samples are analyzed using HPGe detector based on high resolution gamma spectrometric system. The activity of the three radionuclides 226Ra, 232Th and 40K were found to be in the range of BDL–47.68, 7.65–59.08 and BDL–260.65 Bq kg?1 respectively. The mean gamma absorbed dose rate in air above 1 m from ground is estimated to be 34.47 nGy h?1. Annual effective dose equivalent and the radium equivalent activity were within the limits in the present study and it is found that the activity of the radionuclides are comparable with the worldwide literature values. Also the external hazard indices for the soil samples of Bidar district were within the limit of unity. 相似文献
74.
The nonlinear optical properties of coumarin 343 (C343) dye-attached TiO2 nanoparticles in the size range 5–8 nm adsorbed at the interface of water/1,2-dichloroethane have been studied by using the
surface second harmonic generation technique. No second harmonic (SH) response was observed from the bare TiO2 nanoparticles adsorbed at the interface, however, a strong SH response was measured from the dye molecules attached at the
surfaces of the nanoparticles. The increase in the SH intensity with the increase of TiO2 nanoparticle concentration in the aqueous solution of C343 is mainly due to the pre-alignment of the dye molecules at the
surfaces of nanoparticles and is partly due to the third-order polarization contribution of the nanoparticles to the observed
total SH response. 相似文献
75.
Journal of Fluorescence - The methyl orange [C14H14N3SO3Na], an azo dye exhibited strong emission and large Stokes shift in various solvents, and the largest shift (Δλ = 125.51nm or... 相似文献
76.
77.
78.
Asha A. Kembhavi Anuradha Kulkarni Aditi Pant 《Applied biochemistry and biotechnology》1993,38(1-2):83-92
The proteolytic activity produced by aBacillus subtilis isolated from a hot spring was investigated. Maximum protease production was obtained after 38 h of fermentation. Effects of various carbon and nitrogen sources indicate the requirement of starch and bacteriological peptone to be the best inducers for maximum protease production. Requirement for phosphorus was very evident, and the protease was secreted over a wide range of pH 5–11. The partially purified enzyme was stable at 60°C for 30 min. Calcium ions were effective in stabilizing the enzyme, especially at higher temperature. The enzyme was extremely salt tolerant and retained 100% activity in 5M NaCl over 96 h. The molecular weight of the purified enzymes as determined by SDS-PAGE was 28,000. The enzyme was completely inactivated by PMSF, but little affected by urea, sodium dodecyl sulfate, and sodium tripoly phosphate. 相似文献
79.
R K Choudhury D M Nadkarni V S Ambekar B V Dinesh A Saxena M S Samant D C Biswas L M Pant 《Pramana》1995,44(2):177-182
The32S +27Al reaction was studied to investigate the deep inelastic collisions at a bombarding energy of 130 MeV which is well above
the Coulomb barrier. The energy distributions of the binary decay products of 6⩽Z⩽10 were determined using a large area position sensitive ionization chamber. The average kinetic energies of the reaction
products indicate that the exit shapes correspond to highly stretched scission configurations in the deep-inelastic processes. 相似文献
80.
H. C. Pant S. Sharma T. P. S. Nathan T. Desai 《Applied Physics A: Materials Science & Processing》1980,23(2):183-187
Optical energy balance in plasmas produced by irradiating solid targets by highpower laser pulses, has been experimentally
determined. The total light scattered has been measured as a function of the laser intensity and the irratiated spot diameter.
It has been found that the net light absorption does not depend on the laser intensity alone, but is also affected by the
irradiated spot area. It has also been observed that diffuse back reflection becomes a dominant loss mechanism at high incident
flux and small irradiated spot area. 相似文献