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161.
162.
163.
K. Venkateswarlu 《Proceedings Mathematical Sciences》1940,12(5):453-461
164.
D. Kumar Reddy V. Shekhar T. Srikhanth Reddy S. Purushotham Reddy Y. Venkateswarlu 《Tetrahedron: Asymmetry》2009,20(20):2315-2319
A simple and highly efficient stereoselective synthetic route has been developed for the synthesis of (R)-rugulactone, a 6-arylalkyl-5,6-dihydro-2H-pyran-2-one, from readily available substrates such as 1,3-propanediol and 3-phenyl-1-propanal employing Keck’s asymmetric allylation and cross metathesis as key steps. 相似文献
165.
2,4,6‐Trichloro‐1,3,5‐triazine (TCT, cyanuric chloride) was found to mediate the regio‐ and stereoselective ring opening of epoxides in H2O in the presence of morpholine at room temperature to afford the corresponding β‐chlorohydrins in excellent yields (Table). The transformation is very simple, fast, efficient, and ecologically beneficial. 相似文献
166.
The Kantowski-Sachs cosmological solutions of massive strings have been studied in the presence of zero-mass scalar field coupled with bulk viscosity. It is assumed that the coefficient of bulk viscosity is a power function of energy density of massive strings. Further we have considered the cosmological parameter as a function of cosmic time. We obtained the general solution of the field equations in polynomial and exponential forms respectively. The behaviors of these models are also discussed in the presence as well as in the absence of bulk. 相似文献
167.
Olivine-structured LiMnPO4 nanoparticles were prepared by microwave-assisted solvothermal method. The as obtained LiMnPO4 sample was characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and impedance spectroscopy techniques. The XRD pattern confirms the formation of LiMnPO4 phase with an orthorhombic structure. The electrical conductivity of the sample at room temperature is found to be 1.2654?×?10?7 S cm?1. Dielectric spectra show an increase in dielectric constant with increase of temperature. The dielectric loss spectra reveal the predomination of DC conduction in the sample. The modulus studies indicate the non-Debye nature of the sample which corresponds to the distribution of elements in the sample. Galvanostatic battery testing showed that LiMnPO4 nanoparticles displayed good cycleability in 30 cycles. 相似文献
168.
Bioanalysis of tolvaptan,a novel AVP‐V2 receptor antagonist in human plasma by a novel LC‐ESI‐MS/MS method: a pharmacokinetic application in healthy South Indian male subjects 下载免费PDF全文
Venkata Ramu Derangula Nageswara Rao Pilli Babu Rao Bhukya Chalapathi Rao Pulipati Vinayender Adireddy Venkateswarlu Ponneri 《Biomedical chromatography : BMC》2014,28(3):332-340
A simple, rapid and sensitive liquid chromatography/electrospray ionization tandem mass spectrometry (LC‐ESI‐MS/MS) assay method is proposed for the determination of tolvaptan in human plasma samples using tolvaptan d7 as internal standard (IS). Analyte and the IS were extracted from 100 μL of human plasma via simple liquid–liquid extraction. The chromatographic separation was achieved on a C18 column using a mixture of methanol and 0.1% formic acid buffer (80:20, v/v) as the mobile phase at a flow rate of 1.0 mL/min. The calibration curve obtained was linear (r2 ≥ 0.99) over the concentration range of 0.05–501 ng/mL. Method validation was performed as per US Food and Drug Administration guidelines and the results met the acceptance criteria. The intra‐day and inter‐day precision (coefficient of variation) and accuracy results in three validation batches across five concentration levels were well within the acceptance limits. A run time of 2.0 min for each sample made it possible to analyze more samples in a short time, thus increasing the productivity. The proposed method was successfully applied to a pharmacokinetic study of 15 mg and 60 mg tolvaptan tablet formulation in healthy South Indian male subjects under fasting condition. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
169.
Vinayender Adireddy Nageswara Rao Pilli Venkata Ramu Derangula Shobha Rani Satla Chinna Veera Badraiah Ganguri Venkateswarlu Ponneri 《Biomedical chromatography : BMC》2013,27(8):1062-1069
This paper describes a simple, rapid and sensitive liquid chromatography/tandem mass spectrometry assay for the determination of aliskiren in human plasma using nevirapine as an internal standard. Analyte and the internal standard were extracted from 100 μL of human plasma via liquid–liquid extraction using tert‐butyl methyl ether. The chromatographic separation was achieved on a C18 column using a mixture of acetonitrile and 0.1% formic acid (90:10, v/v) as the mobile phase at a flow rate of 0.9 mL/min. The calibration curve obtained was linear (r2 ≥ 0.99) over the concentration range of 0.10–1013 ng/mL. Method validation was performed as per US Food and Drug Administration guidelines and the results met the acceptance criteria. A run time of 2.2 min for each sample made it possible to analyze a greater number of samples in a short time, thus increasing the productivity. The proposed method was found to be applicable to clinical studies. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
170.
Singanaboina Rajaram Udugu Ramulu Dasari Ramesh Peddikotla Prabhakar Yenamandra Venkateswarlu 《Helvetica chimica acta》2013,96(11):2115-2123
An efficient stereoselective total synthesis of the bioactive 14‐membered natural macrocyclic bislactone 4‐ketoclonostachydiol is described. The strategy involves a Jacobsen's hydrolytic kinetic resolution (HKR), epoxide opening, MacMillan α‐hydroxylation, Horner? Wadsworth? Emmons olefination, a Grignard reaction, and Hoveyda? Grubbs‐II‐catalyzed ring‐closing metathesis (RCM) as key steps. 相似文献