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排序方式: 共有514条查询结果,搜索用时 15 毫秒
1.
Kumar B. Ravi Kumar A. Kishore Reddy B. Srinivas Shashikala K. Laxminarayana E. 《Russian Journal of Organic Chemistry》2022,58(4):580-583
Russian Journal of Organic Chemistry - tert-Butyl 4-[(E)-but-1-en-3-yn-1-yl]-3-{[tert-butyl(dimethyl)silyl]oxy}-1H-indole-1-carboxylate has been synthesized with a good yield and selectivity... 相似文献
2.
Shaik A. Rao A. T. Venkatarao D. V. Rao S. V. M. Mohan Kishore P. V. V. N. 《Russian Journal of Organic Chemistry》2020,56(12):2179-2187
Russian Journal of Organic Chemistry - A series of novel 1,2,4-triazole nonsteroidal anti-inflammatory drugs (NSAIDs) derived from etodolac were designed and synthesized. The synthesized compounds... 相似文献
3.
Sensitive method for the determination of paricalcitol by liquid chromatography and mass spectrometry and its application to a clinical pharmacokinetic study 下载免费PDF全文
Kishore Kumar Hotha Ramesh Mullangi Ravindranath Lakshmanarao Krishnarao Swapan Roychowdhury 《Biomedical chromatography : BMC》2015,29(3):452-458
A highly sensitive, specific and rapid LC‐ESI‐MS/MS method has been developed and validated for the quantification of paricalcitol (PAR) in human plasma (500 μL) using paricalcitol‐d6 (PAR‐d6) as an internal standard (IS) as per regulatory guidelines. A liquid–liquid extraction method was used to extract the analyte and IS from human plasma. Chromatography was achieved on Zorbax SB C18 column using an isocratic mobile phase in a gradient flow. The total chromatographic run time was 6.0 min and the elution of PAR and PAR‐d6 occurred at ~2.6 min. A linear response function was established for the range of concentrations 10–500 pg/mL in human plasma. The intra‐ and inter‐day accuracy and precision values for PAR met the acceptance criteria. The validated assay was applied to quantitate PAR concentrations in human plasma following oral administration of 4 µg capsules to humans. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
4.
Synthesis of Small‐Sized,Porous, and Low‐Toxic Magnetite Nanoparticles by Thin POSS Silica Coating 下载免费PDF全文
Dr. Swee Kuan Yen D. Prathyusha Varma Wei Mei Guo Dr. Vincent H. B. Ho Dr. Vimalan Vijayaragavan Dr. Parasuraman Padmanabhan Prof. Kishore Bhakoo Prof. Subramanian Tamil Selvan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(10):3914-3918
In this communication, we report the synthesis of small‐sized (<10 nm), water‐soluble, magnetic nanoparticles (MNPs) coated with polyhedral oligomeric silsesquioxanes (POSS), which contain either polyethylene glycol (PEG) or octa(tetramethylammonium) (OctaTMA) as functional groups. The POSS‐coated MNPs exhibit superparamagnetic behavior with saturation magnetic moments (51–53 emu g?1) comparable to silica‐coated MNPs. They also provide good colloidal stability at different pH and salt concentrations, and low cytotoxicity to MCF‐7 human breast epithelial cells. The relaxivity data and magnetic resonance (MR) phantom images demonstrate the potential application of these MNPs in bioimaging. 相似文献
5.
Dr. Kishore Natte Dr. Helfried Neumann Prof. Dr. Matthias Beller Dr. Rajenahally V. Jagadeesh 《Angewandte Chemie (International ed. in English)》2017,56(23):6384-6394
Methanol is used as a common solvent, cost-effective reagent, and sustainable feedstock for value-added chemicals, pharmaceuticals, and materials. Among the various applications, the utilization of methanol as a C1 source for the formation of carbon–carbon, carbon–nitrogen, and carbon–oxygen bonds continues to be important in organic synthesis and drug discovery. In particular, the synthesis of C-, N-, and O-methylated products is of central interest because these motifs are found in a large number of natural products as well as fine and bulk chemicals. In this Minireview, we summarize the utilization of methanol as a C1 source in methylation, methoxylation, formylation, methoxycarbonylation, and oxidative methyl ester formation reactions. 相似文献
6.
Jigar Panchal Sonika Jain Pankaj Kumar Jain Dharma Kishore Jaya Dwivedi 《Journal of heterocyclic chemistry》2021,58(11):2049-2066
The greener methodology to synthesize s-triazine derivatives (also known as TCT) is described, including synthesis through microwave, ultrasound, and solvent-free conditions. This review mainly focuses on reactions of TCT (2,4,6-trichloro-1,3,5-triazine) with various substituents having amine and hydroxy functionalities to give corresponding triazine derivatives under a greener approach. The results of reactions indicate that, unlike classical methods, green methods result in better yields of the product, through a rapid reaction, under mild reaction conditions, and by easy workup procedures. 相似文献
7.
Kumar A. Kishore Sunitha V. Ramesh G. Jeshma K. 《Russian Journal of General Chemistry》2021,91(12):2546-2553
Russian Journal of General Chemistry - A series of novel 1,2,3-triazoles (8a–8m) were synthesized using click chemistry in excellent yields and were characterized by IR, NMR, MASS... 相似文献
8.
Dr. Lin He Dr. Kishore Natte Dr. Jabor Rabeah Dr. Christoph Taeschler Dr. Helfried Neumann Prof. Dr. Angelika Brückner Prof. Dr. Matthias Beller 《Angewandte Chemie (International ed. in English)》2015,54(14):4320-4324
Fluorinated organic compounds are gaining increasing interest for life science applications. The replacement of hydrogen in arenes or heteroarenes by a perfluoroalkyl group has a profound influence on the physical and biological properties of such building blocks. Here, an operationally simple protocol for the direct C? H perfluoroalkylation of (hetero)arenes with RfI or RfBr has been developed, using a robust supported platinum catalyst. The ready availability of the starting materials, the excellent substrate tolerance, and the reusability of the catalyst make this method attractive for the synthesis of a variety of perfluoroalkyl‐substituted aromatic compounds. Preliminary mechanistic studies revealed the formation of radicals to be crucial in the reaction system. 相似文献
9.
10.
Highly Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles in the Presence of Diazabicycloundecene 下载免费PDF全文
New highly efficient method for the cyclization of acylamidoximes in the presence of diazabicycloundecene was developed and incorporated into a general and practical one‐pot synthesis of 1,2,4‐oxadiazoles (11 examples, 85–97% yields). 相似文献