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21.
A. Babulreddy R. V. Hymavathi Md. Manzoor Hussain G. Narayana Swamy 《Journal of heterocyclic chemistry》2013,50(3):727-733
A new class of methyleneamine‐linked bis‐heterocycles that exhibit antimicrobial activity was synthesized. Bromination of 1 followed by condensation with thiourea gave 3 . The reaction of 3 with propargyl bromide in dry toluene under inert atmosphere led to the formation of 4 . Its subsequent reaction with different nitrile oxides using CuSO4.5H2O–sodiumascorbate system in a 2:1 mixture of water and tert‐butyl alcohol yielded the title compounds 6a , 6b , 6c , 6d , 6e , 6f , 6g , 6h , 6i , 6j , 6k , 6l in good yields. The identities of these compounds were confirmed following elemental analysis, IR, 1H, 13C NMR, and mass spectral studies. All the title compounds exhibited pronounced in vitro antibacterial and antifungal activities. 相似文献
22.
Reaction of 2-pyridylmagnesium chlorides with N,N-dialkyl arylamides afford exclusively 2-(aroyl) pyridines in high yields and purity without the formation of any tertiary alcohol. This method employs easily available raw materials and avoids the use of hazardous lithium reagents and cryogenic conditions. Further, preferential reactivity of this Grignard reagent with N,N-dialkyl arylamides over its carbonitrile counterparts offers a variety of 2-(aroyl) pyridines including the ones containing carbonitrile groups on the aryl ring. 相似文献
23.
RITVA LINDBERG GORAN SUNDHOLM JOHAN SJö BLOM PETRI AHONEN ESKO I. KAUPPINEN 《Journal of Dispersion Science and Technology》2013,34(1-2):715-722
The zeta-potentials of silica, copper, platinum and gold particles have been measured as a function of pH. The isoelectric points were found to be at pH 3.0, 5.8, 3.0 and 3.5, respectively. In the pH range 3.0 to 5.8 copper and silica particles are oppositely charged and accordingly the coating of silica with copper particles could be demonstrated. In the case of gold and platinum the sign of the charge is such that direct adhesion to silica particles cannot be expected and this was also demonstrated in the case of platinum. 相似文献
24.
Raunak Tamrakar Vikas Dubey N. Kumar Swamy Ratnesh Tiwari S. V. N. Pammi P. V. Ramakrishna 《Research on Chemical Intermediates》2013,39(8):3919-3923
The present paper reports thermoluminescence (TL) glow curves of Eu3+-doped Y2O3 phosphor with different ultraviolet (UV) exposure times. The glow peak shows second-order kinetics of Eu3+-doped Y2O3, and corresponding kinetic parameters were evaluated using the peak shape method. Calculations of trap depth were carried out using different methods. The kinetics order, activation energy, and frequency factor were calculated. The recorded glow curve shifts towards higher intensity with longer UV exposure. The heating rate used for recording TL was 3.0 °C s?1. Particle size and structure were verified by X-ray diffraction (XRD) pattern and morphology by scanning electron microscopy (SEM) imaging. 相似文献
25.
Mahender Reddy Marri Swamy PerakaArun Kumar Macharla Naresh MamedaSrujana Kodumuri Narender Nama 《Tetrahedron letters》2014
A new and efficient protocol is described for the one-pot synthesis of benzimidazoles from a variety of aryl alcohols and 1,2-diaminoarenes. The yields were ranging from moderate to excellent. Moreover, the present method is utilizing alcohols instead of aldehydes and the reactions are carried out under solvent- and catalyst-free conditions, offering an environmentally benign process. 相似文献
26.
Divakar Vishwanath Swamy S. Girimanchanaika Dukanya Dukanya Shobith Rangappa Ji-Rui Yang Vijay Pandey Peter E. Lobie Basappa Basappa 《Molecules (Basel, Switzerland)》2022,27(3)
Novel PARP inhibitors with selective mode-of-action have been approved for clinical use. Herein, oxadiazole based ligands that are predicted to target PARP-1 have been synthesized and screened for the loss of cell viability in mammary carcinoma cells, wherein seven compounds were observed to possess significant IC50 values in the range of 1.4 to 25 µM. Furthermore, compound 5u, inhibited the viability of MCF-7 cells with an IC50 value of 1.4µM, when compared to Olaparib (IC50 = 3.2 µM). Compound 5s also decreased cell viability in MCF-7 and MDA-MB-231 cells with IC50 values of 15.3 and 19.2 µM, respectively. Treatment of MCF-7 cells with compounds 5u and 5s produced PARP cleavage, H2AX phosphorylation and CASPASE-3 activation comparable to that observed with Olaparib. Compounds 5u and 5s also decreased foci-formation and 3D Matrigel growth of MCF-7 cells equivalent to or greater than that observed with Olaparib. Finally, in silico analysis demonstrated binding of compound 5s towardsthe catalytic site of PARP-1, indicating that these novel oxadiazoles synthesized herein may serve as exemplars for the development of new therapeutics in cancer. 相似文献
27.
J. Manjunath Swamy Narendra Kamath Anil Kumar Radha Shekar Nuggehally R. Srinivas Fjalar Kristjansson 《Biomedical chromatography : BMC》2010,24(5):528-534
Sensitivity enhancement via summation of multiple MRM transition pairs is gaining popularity in tandem mass spectrometric assays. Numerous validation experiments describing the assays for two model substrates, clopidogrel and ramiprilat, were performed. The quantitation of clopidogrel was achieved by the summation of transition pairs m/z 322.2 to m/z 212.0 and m/z 322.2 to m/z 184.0, while that of ramiprilat was achieved by the summation of transition pairs m/z 389.2 to m/z 206.1 and m/z 389.2 to m/z156.1. The use of summation approach achieved sensitivities of >2 fold for both compounds as compared with the reported single MRM transition pair assays. The validation experiments addressed some important assay development issues, such as: (a) lack of impact of matrix effect; (b) unequivocal verification of the percentage contribution of each MRM transition pair towards sensitivity; (c) sensitivity enhancement factor achieved by summation approach of MRM transition pairs; and (d) accurate prediction of quality control samples using summation approach vs a single MRM transition pair. In summary, the appropriateness of using two MRM transition pairs for quantitation was demonstrated for both clopidogrel and ramiprilat. Additionally, pharmacokinetic application of the MRM transition pair assays using a summation approach was established for the two compounds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
28.
During the last 50 years extensive experimental investigation has been carried out on the chemical effects of ultrasound, but limited work has been reported on modeling. This paper presents a new model in which a numerical calculation of the three-dimensional linear sound pressure field distribution in a commonly used sonoreactor containing three transducers is carried out. In this model the inhomogeneous three-dimensional time-dependent wave equation was solved using the finite difference approach. The modeled results are then compared with the experimentally measured values, and the agreement, in general, is found to be good. Further, our modeling studies have an advantage, since they clearly describe the continuous sound pressure field structure, unlike previously reported results in which some information is missing due to limited intermittent measured points. 相似文献
29.
The mean spherical model (MSM) equation has been solved for the aquare-well potential. Comparison of the MSM results with the simulation results shows the MSM radial distribution function and energy to be satisfactory in the liquid states. 相似文献
30.
van Enk SJ 《Physical review letters》2000,84(4):789; author reply 790