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81.
Nirupam Das Biswajit Dash Meenakshi Dhanawat Sushant Kumar Shrivastava 《Chemical Papers》2012,66(1):67-74
Ten derivatives of N1 substituted/unsubstituted 5-(4-chlorophenyl)-3-(2-thienyl) pyrazoline were synthesised from chalcone-like
intermediate and substituted phenyl hydrazines, hydrazine hydrate, and semi/thiosemicarbazide. The chemical structure of compounds
was confirmed by means of IR, 1H NMR, mass spectroscopy, and elemental analysis. The antidepressant and anticonvulsant activities were investigated by Porsolt’s
behavioural despair test (forced swimming) and maximum electroshock seizure test, respectively. Rota-Rod test was performed
to assess any probable changes in motor coordination induced by the test compounds. Four compounds (IId, IIg, IIi, and IIj) exhibited good activity profile against depression and docking studies confirmed their consensual interaction with monoamine
oxidase A. In addition, compounds IIc and IIe showed protection against MES-induced seizures. 相似文献
82.
Prashant T. Mistry Nimesh R. Kamdar Dhaval D. Haveliwala Saurabh K. Patel 《Journal of heterocyclic chemistry》2012,49(2):349-357
A variety of pyrano[2,3‐d]pyrimidine‐5‐one derivatives 5 , 5a , 5b , 5c , 5d , 5e , 5f , 5g , 5h , 5i , 5j , 6 , 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j have been synthesized from 6‐amino‐4‐(substituted phenyl)‐5‐cyano‐3‐methyl‐1‐phenyl‐1,4‐dihydropyrano[2,3‐c]pyrazole derivatives 4a , 4b , 4c , 4d , 4e , 4f , 4g , 4h , 4i , 4j via cyclization using formic acid and acetic acid. All the newly synthesized compounds have been characterized by IR, 1H NMR, 13C NMR, and elemental analysis. All the synthesized compounds have been screened for antibacterial, antifungal and antitubercular activity. J. Heterocyclic Chem., (2012). 相似文献
83.
Dhruba Gupta C Samanta R Kanungo P Basu Subinit Roy S Kailas A Chatterjee B J Roy K Mahata A Samant A Shrivastava 《Pramana》2001,57(1):209-213
Inclusive cross sections of α particles and tritons from the breakup of 42 MeV 7Li by 12C and 197Au targets are presented and analysed in the framework of the Serber model. Spectral distortions due to the targets and relevant
reaction mechanisms are discussed. 相似文献
84.
Purnima Shrivastava 《PAMM》2007,7(1):2150043-2150044
Simulating the heat conduction in between a solid conducting body immersed in fluid at a given temperature is a difficult task, particularly when the body is tapered in shape and the costs have to be kept low. The body in question is cylindrical, symmetrical about z-axis, tapered in shape and has been heated to a high temperature before being immersed into the fluid. The heat conduction equation in cylindrical polar coordinates with all derivative boundary conditions is attempted to be solved in two ways – first analytically making use of Bessel's function and then by numerical modelling with the help of Finite Difference method, and equations thus formed have been solved through ADI explicit and Implicit (Peaceman Rachford) scheme on microcomputer. The paper is an account of work already done on this and includes further possibilities for general solution with analytical methods and a suitable low-cost numerical solution. Also possible analogy with flow of fluids have been explored. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
85.
The Ramanujan Journal - In Maier and Tenenbaum (Invent Math 76(1):121–128, 1984), Tenenbaum and the first author proved an old conjecture of Paul Erd?s about the propinquity of divisors... 相似文献
86.
Joshua W. M. MacMillan Katherine M. Marczenko Prof. Dr. Erin R. Johnson Prof. Dr. Saurabh S. Chitnis 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17134-17142
The addition of Sb−H bonds to alkynes was reported recently as a new hydroelementation reaction that exclusively yields anti-Markovnikov Z-olefins from terminal acetylenes. We examine four possible mechanisms that are consistent with the observed stereochemical and regiochemical outcomes. A comprehensive analysis of solvent, substituent, isotope, additive, and temperature effects on hydrostibination reaction rates definitively refutes three ionic mechanisms involving closed-shell charged intermediates. Instead the data support a fourth pathway featuring open-shell neutral intermediates. Density-functional theory (DFT) calculations are consistent with this model, predicting an activation barrier that is in agreement with the experimental value (Eyring analysis) and a rate limiting step that is congruent with the experimental kinetic isotope effect. We therefore conclude that hydrostibination of arylacetylenes is initiated by the generation of stibinyl radicals, which then participate in a cycle featuring SbII and SbIII intermediates to yield the observed Z-olefins as products. This mechanistic understanding will enable rational evolution of hydrostibination as a synthetic methodology. 相似文献
87.
A gauge-invariant Rarita-Schwinger theory of a massive spin-3/2 particle interacting with external electromagnetic, gravitational and dilaton fields is obtained by Kaluza-Klein reduction of a massless Rarita-Schwinger theory with graviational interaction. Fermionic gauge invariance serves to determine the background equations of motion. The couplings with external fields obtained by the Kaluza-Klein reduction are shown to lead to the absence of the classical Velo-Zwanziger problem and on quantizing using Dirac's procedure, the field anticommutators are found to be positive definite. 相似文献
88.
Saurabh D Rindani 《Pramana》1995,45(1):263-276
The prospects of experimental detection ofCP violation ate + e ? and\(pp/p\bar p\) colliders are reviewed. After a general discussion on the quantities which can measureCP violation and on the implications of theCPT theorem, various possibilities of measuringCP violation arising outside the standard model are taken up.CP violation in leptonic processes, especially polarization effects ine + e ?→l + l ? are discussed next.CP violation in\(t\overline t \) andW + W ? production and decay is also described. 相似文献
89.
Montmorillonite clay mineral shows remarkable ion exchange, intercalation and swelling properties. It can act as a good host for large organic molecules. Intercalated coordination compounds can be prepared in the interlayer spaces of montmorillonite structure. Cu(II)- and Ni(II)- exchanged montmorillonite sorb 8-hydroxyquinoline (oxine) to form corresponding coordination compounds of the exchanged metal ions. Such compounds have been characterised by means of elemental analysts, infrared spectroscopy, magnetic susceptibility data and X-ray diffraction. These compound show good thermal stability. 相似文献
90.
A procedure is described in which gold(III) is quantitatively extracted with an amidine into chloroform over the acidity range pH 3.0–11.0 M HCl, followed by its selective spectrophotometric determination by interaction of the extract with methylene blue in the pH range 3.0–9.0. The molar absorptivity of the coloured complex formed by extraction with ten different amidines and methylene blue reaction lie in the range 1.1 × 104?6.5 × 104 1 mol?1 cm?1 at λmax (650 nm) in chloroform. The simplest compound, N, N′-diphenylbenzamidine, was chosen for detailed study. The limit of detection is 5 μg Au l?1. The method is free from interferences from the metals that are generally associated with gold. The method is simple, reproducible and applicable to the accurate recovery of gold from low-grade ores containing the metal at levels of > 1.5 μg g?1. 相似文献