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排序方式: 共有343条查询结果,搜索用时 46 毫秒
1.
Ravula Sharada Nukala Satheesh Kumar Thirukovela Narasimha Swamy Sirassu Narsimha Dasari Gouthami Kurma Srimathi Bandari Srinivas 《Russian Journal of General Chemistry》2022,92(4):702-708
Russian Journal of General Chemistry - In the current study, some new quinoxaline linked 1,3,4-oxadiazole sulfonamide hybrids have been designed, synthesized and characterized by IR, 1H and 13C... 相似文献
2.
Palladium-catalyzed highly regioselective synthesis of benzotriazole appended benzosultams by the tandem-cyclization of functionalized ynamides with benzotriazoles has been accomplished. This transformation involves the formation of both CN and CC bonds in a single step. Donor solvents appear to enhance the yields of the products. The methodology is also applicable for the generation of triazole/tetrazole appended benzosultams. 相似文献
3.
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
4.
S. T.P.V.J. Swamy 《光谱学快报》2013,46(11):833-838
Compton spectrum due to L-shell electrons of thorium has been measured by the coincidence technique, using 279 keV incident gamma photons. The influence of L-shell electron momenta on the distribution of the scattered photons has been studied with reference to the Compton profile due to free electrons and compared with the exact and impulse hydrogenic theoretical models. Significant deviations are found between experimental and theoretical Compton spectra. 相似文献
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7.
Musa A. Said K. C. Kumara Swamy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Hydrolysis of several cyclic aminophosphites are discussed and compared with that of cyclic chloro/ phenoxy phosphites. An X-ray structure of a hydrolysis product, (C6H11NH3)+O?P(O)(H)(2,2′-OC6H4-C6H4OH) has been determined. 相似文献
8.
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
9.
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
10.
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