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31.
Murthy I. S. Sreenivasulu R. Alluraiah G. Ramesh Raju R. 《Russian Journal of General Chemistry》2019,89(8):1718-1723
Russian Journal of General Chemistry - A series of novel 1,2-isoxazole-pyridobenzimidazole is synthesized. Structures of the products are supported by 1H and 13C NMR, and mass spectra. All... 相似文献
32.
33.
Harsha K. Tripathy S. V. Nair Manju Rama Murthy Bestha Vinay Kiran Sreekanth Dittakavi Ramesh Mullangi 《Biomedical chromatography : BMC》2022,36(8):e5387
In this study, we report the development and validation of an LC–tandem mass spectrometry method for the simultaneous quantitation of bendamustine and copanlisib in mouse plasma as per the US FDA regulatory guidelines. The sample processing involves extraction of bendamustine and copanlisib along with internal standard (IS; warfarin) from 50 μL mouse plasma using a liquid–liquid extraction method. The chromatographic separation of bendamustine, copanlisib and the IS was achieved on an Atlantis dC18 column using an isocratic mobile phase (5 mM ammonium acetate:methanol, 20:80 v/v). Bendamustine, copanlisib and the IS eluted at 0.88, 1.39 and 0.74 min, respectively, with a total run time of 2.5 min. The calibration curve ranged from 3.99–2996 and 4.33–3248 ng/mL for bendamustine and copanlisib, respectively. Inter- and intra-day precision and accuracy, stability in processed samples and upon storage, dilution integrity and incurred sample reanalysis were investigated for both the analytes. The intra- and inter-day precisions were in the ranges of 2.01%–5.05% and 2.74%–6.13% and 1.98%–7.64 and 8.62%–9.04% for bendamustine and copanlisib, respectively. Stability studies showed that both analytes were stable on bench top for 6 h, in auto-sampler for 24 and at −80°C for 30 days. The validated method was successfully applied to a pharmacokinetic study in mice. 相似文献
34.
D. K. Padma S. K. Vijayalakshmi A. R. Vasudeva Murthy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(2):129-130
Abstract Solid complexes of thiophosphoryl fluoride and thiophosphoryl chloride with dimethyl sulphoxide (DMSO) have been prepared and characterized. 相似文献
35.
Abstract Computer simulation studies of the energy distribution of transmitted ions such as alpha-particles, He-, and B-ions through crystalline silicon, using the enhanced binary-collision cascade simulator MARLOWE, will be reviewed. The enhancement includes an additional electronic-energy loss (EEL) model which takes into account explicitly both the target electron density variation via the structure factors and the electron density of the projectile. Investigations of the stopping power for He ions and protons in silicon, at intermediate- and high-energies, based on the adapted EEL model and a velocity-dependent effective charge will be presented. The overall agreement between the calculated and experimentally determined stopping power data and the simulated and measured transmission spectra will be demonstrated. Effects of energy-loss straggling, core-electron contribution to the energy loss at high-energies and charge-state effects at low energies on the transmission spectra will also be discussed. 相似文献
36.
Harika Patnala Hanna S. Abbo Krishna Murthy Potla 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):1035-1039
AbstractAn efficient and eco-friendly protocol has been accomplished for a series of novel α-diaminophosphonates by a one-pot, three-component system via Kabachnik-Fields reaction of 4,4′-methylenedianiline, a variety of aryl/heteroaryl aldehydes and diphenylphosphite employing polyethylene glycol (PEG-400) as a green solvent at 80?°C. All products were obtained in good to excellent yields (80–95%). The identity of the new synthesized compounds was confirmed by IR, 1H, 13C, and 31P NMR, LC-MS and elemental analysis. In vivo anti-viral activity was evaluated against tobacco mosaic virus (TMV). Compounds 4b, 4c, 4j and 4k exhibited the highest anti-viral activities against tobacco mosaic virus (TMV) when compared with the standard drug ningnanmycin. 相似文献
37.
Ramu Surakanti Sumalatha Sanivarapu Chiranjeevi Thulluri Pravin S. Iyer Raghuram S. Tangirala Rambabu Gundla Dr. Uma Addepally Y. L. N. Murthy Lakshmi Velide Dr. Subhabrata Sen 《化学:亚洲杂志》2013,8(6):1168-1176
An elegant reagent‐controlled strategy has been developed for the generation of a diverse range of biologically active scaffolds from a chiral bicyclic lactam. Reduction of the chiral lactam with LAH or alkylation with LHMDS to trigger different cyclization reactions have been shown to generate privileged scaffolds, such as pyrrolidines, indolines, and cyclotryptamines. Their amenability to substitution allows us to create various compound libraries by using these scaffolds. In silico studies were used to estimate the drug‐like properties of these compounds. Selected compounds were subjected to anticancer screening by using three different cell lines. In addition, all these compounds were subjected to antibacterial screening to gauge the spectrum of biological activity that was conferred by our DOS methodology. Gratifyingly, with no additional iterative cycles, our method directly generated anticancer compounds with potency at low nanomolar concentrations, as represented by spiroindoline 14 . 相似文献
38.
Konkala Karnakar Katla Ramesh Sabbavarapu Narayana Murthy Yadavalli Venkata Durga Nageswar 《Helvetica chimica acta》2013,96(12):2276-2281
The first example of the stereoselective synthesis of (Z)‐ and (E)‐allyl aryl sulfides and selenides from Baylis? Hillman acetates under neutral conditions in H2O by supramolecular catalysis involving β‐cyclodextrin is reported. β‐Cyclodextrin can be recovered and reused. The reaction is very efficient in providing allyl aryl sulfides and selenides in good‐to‐excellent yields with clean reaction profiles under mild reaction conditions. 相似文献
39.
An efficient, economically viable process has been developed for large‐scale preparation of donepezil HCl (1), an anti‐Alzheimer's agent. The process involves the condensation of 5,6‐dimethoxy‐1‐indanone (3) and 1‐benzyl‐4‐piperidinecarboxaldehyde (4) in the presence of alkalimetal carbonates at elevated temperature to yield 1‐benzyl‐4‐[(5,6‐dimethoxy‐1‐indanone)‐2‐yidenyl] methyl piperidine (2), the key intermediate in the synthesis of donepezil. Hydrogenation of 2 yields donepezil. 相似文献
40.
The synthesis and characterization of five homologous series of symmetrical compounds composed of banana-shaped molecules containing a biphenyl moiety are reported. All these compounds are non-Schiff's bases and are esters. The effects of lateral substituents such as fluoro, methyl and ethyl in the side arms of these molecules are examined. These substituents have a strong influence in reducing the clearing temperatures. Banana phases such as B1, B2 and B6 were observed in the above series of compounds. The mesophases were characterized by a combination of polarizing optical microscopy, differential scanning calorimetry, X-ray diffraction and electro-optic studies. 相似文献