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41.
Naiem Ahmad Wani Vivek Kumar Gupta Rajni Kant Subrayashastry Aravinda Rajkishor Rai 《Acta Crystallographica. Section C, Structural Chemistry》2013,69(10):1170-1172
2‐{1‐[(Pyrazin‐2‐ylformamido)methyl]cyclohexyl}acetic acid (Pyr‐Gpn‐OH), C14H19N3O3, is an N‐protected derivative of gabapentin (Gpn). The compound crystallizes in the triclinic space group P and the molecular conformation is stabilized by intramolecular five‐ (C5) and seven‐membered (C7) hydrogen‐bonded rings. The packing of the molecules reveals intermolecular O—H...O and C—H...N hydrogen bonds, together with π–π interactions. 相似文献
42.
V. Balasubramaniyan P. Balasubramaniyan M. J. Wani 《Journal of Chemical Sciences》1991,103(5):621-629
Maleimides (2a−j) react with thiourea in refluxing ethanol to yield the corresponding N-aryl α-(2,3,4,5-tetrahydro-4-oxo-l,3-thiazole-5-yl)
acetamides (6a−j) in 72–85%. The spectral and analytical data are consistent with the assigned structures for6a−j. Under similar conditions, isomalemides (3a−b and3d−f) furnish the corresponding6a−b and6d−f in 76–86%. While maleanilic acid (4a) itself failed to react with thiourea,4b−ē,4i and4j yielded a mixture of the corresponding6b−ē,6i and6j in 2–50% and fumaranilic acids (7b−ē,7i and7j) in 50–80%. Methyl maleanilates (5b,5d−f and5i) gave6b,6d−f and6i in 78–85%. The reaction course of Raney nickel desulphurisation of6a−b,6d,6f and mass spectral fragmentation of6b support the assigned structures.
Part XXI 1991 Org. Prep. Proc. Inter. (in press) 相似文献
43.
R. Z. Sayyed S. S. Shaikh S. J. Wani Md Tabish Rehman Mohammad F. Al Ajmi Shafiul Haque Hesham Ali El Enshasy 《Molecules (Basel, Switzerland)》2021,26(9)
The present study was aimed to evaluate the suitability of agro-wastes and crude vegetable oils for the cost-effective production of poly-β-hydroxybutyrate (PHB), to evaluate growth kinetics and PHB production in Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 with these carbon substrates and to study the biodegradation of PHB accumulated by these cultures. Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1 accumulates higher amounts of PHB corn (79.90% of dry cell mass) and rice straw (66.22% of dry cell mass) medium respectively. The kinetic model suggests that the Pseudomonas sp. RZS1 follows the Monod model more closely than A. faecalis RZS4. Both the cultures degrade their PHB extract under the influence of PHB depolymerase. Corn waste and rice straw appear as the best and cost-effective substrates for the sustainable production of PHB from Alcaligenes faecalis RZS4 and Pseudomonas sp. RZS1. The biopolymer accumulated by these organisms is biodegradable in nature. The agro-wastes and crude vegetable oils are good and low-cost sources of nutrients for the growth and production of PHB and other metabolites. Their use would lower the production cost of PHB and the low-cost production will reduce the sailing price of PHB-based products. This would promote the large-scale commercialization and popularization of PHB as an ecofriendly bioplastic/biopolymer. 相似文献
44.
Among the perovskites, the rare earth manganites find application in several electrochemical devices because of their enhanced thermodynamic stability. In this paper, we present the results obtained on the preparation and characterization of La0.95MnO3+δ and Sm0.95MnO3+δ which were prepared by the solid state and sol–gel methods. XRD characterization of the manganites indicated that the crystal structure depends on the method of preparation and heat treatments. The ratio of Mn3+ to Mn4+ in these samples also depended on the method of preparation and heat treatments, as indicated by thermogravimetric (TG) and temperature programmed reduction (TPR) studies in Ar + 5% H2 atmosphere. The standard molar enthalpy of formation, which is a measure of the thermodynamic stability of these compounds were determined using an isoperibol calorimeter. 相似文献
45.
The formation of a colored charge-transfer (CT) complex between atorvastatin calcium (ATR-Ca) as a n-electron donor and 2, 3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as a π-electron acceptor was investigated, for the first time. The spectral characteristics of the CT complex have been described, and the reaction mechanism has been proved by computational molecular modeling. The reaction was employed in the development of a novel microwell-based spectrophotometric assay for determination of ATR-Ca in its pharmaceutical formulations. The proposed assay was carried out in 96-microwell plates. The absorbance of the colored-CT complex was measured at 460 nm by microwell-plate absorbance reader. The optimum conditions of the reaction and the analytical procedures of the assay were established. Under the optimum conditions, linear relationship with good correlation coefficient (0.9995) was found between the absorbance and the concentration of ATR-Ca in the range of 10-150 μg/well. The limits of detection and quantitation were 5.3 and 15.8 μg/well, respectively. No interference was observed from the additives that are present in the pharmaceutical formulation or from the drugs that are co-formulated with ATR-Ca in its combined formulations. The assay was successfully applied to the analysis of ATR-Ca in its pharmaceutical dosage forms with good accuracy and precision. The assay described herein has great practical value in the routine analysis of ATR-Ca in quality control laboratories, as it has high throughput property, consumes minimum volume of organic solvent thus it offers the reduction in the exposures of the analysts to the toxic effects of organic solvents, and reduction in the analysis cost by 50-fold. Although the proposed assay was validated for ATR-Ca, however, the same methodology could be used for any electron-donating analyte for which a CT reaction can be performed. 相似文献
46.
Density transition based self-focusing of cosh-Gaussian laser beam in plasma with linear absorption has been studied. The field distribution in the plasma is expressed in terms of beam width parameter, decentered parameter, and linear absorption coefficient. The differential equation for the beam width parameter is solved by following Wentzel—Kramers—Brillouin (WKB) and paraxial approximation through parabolic wave equation approach. The behaviour of beam width parameter with dimensionless distance of propagation is studied at optimum values of plasma density, decentered parameter and with different absorption levels in the medium. The results reveal that these parameters can affect the self-focusing significantly. 相似文献
47.
A new DMF complex of U(SO4)2, i.e., U(SO4)2·2.2 DMF, was prepared and characterized using chemical analysis, X-ray powder diffraction studies, IR and measurement of magnetic susceptibility variation with temperature in the temperature range 77–300 K. Pyrolysis of the solvate was studied by means of TG under two different experimental conditions, and the actual thermal degradation path was deduced using a microthermobalance. 相似文献
48.
Using optical techniques, a study was carried out of the etch patterns produced, by diluted oxalic acid and sodium hydroxide solution, at 30°C. Point bottomed and flat bottomed rectangular etch pits nucleated at the sites of dislocations parallel to ‘C’ axis of the crystal are observed. Mostly they are isolated, and randomly distributed. Further, on prolonged etching they penetrate deeper and their eccentricity can be attributed to the inclined nature of dislocations. 相似文献
49.
Jayachithra Ramakrishna Pillai Adil Farooq Wali Godfred Antony Menezes Muneeb U. Rehman Tanveer A. Wani Azher Arafah Seema Zargar Tahir Maqbool Mir 《Molecules (Basel, Switzerland)》2022,27(5)
Physalis angulata L. belongs to the family Solanaceae and is distributed throughout the tropical and subtropical regions. Physalis angulata leaf and fruit extracts were assessed for in vitro anticancer, antioxidant activity, and total phenolic and flavonoid content. The GC-MS technique investigated the chemical composition and structure of bioactive chemicals reported in extracts. The anticancer activity results revealed a decrease in the percentage of anticancer cells’ viability in a concentration- and time-dependent way. We also noticed morphological alterations in the cells, which we believe are related to Physalis angulata extracts. Under light microscopy, we observed that as the concentration of ethanolic extract (fruit and leaves) treated HeLa cells increased, the number of cells began to decrease. 相似文献
50.
Roohi Mohi-ud-din Reyaz Hassan Mir Taha Umair Wani Khalaf F. Alsharif Waqas Alam Ashraf Albrakati Luciano Saso Haroon Khan 《Molecules (Basel, Switzerland)》2022,27(8)
Cancer is a major health problem across the globe, and is expeditiously growing at a faster rate worldwide. The endoplasmic reticulum (ER) is a membranous cell organelle having inextricable links in cellular homeostasis. Altering ER homeostasis initiates various signaling events known as the unfolded protein response (UPR). The basic purpose of the UPR is to reinstate the homeostasis; however, a continuous UPR can stimulate pathways of cell death, such as apoptosis. As a result, there is great perturbation to target particular signaling pathways of ER stress. Flavonoids have gained significant interest as a potential anticancer agent because of their considerable role in causing cytotoxicity of the cancerous cells. Luteolin, a flavonoid isolated from natural products, is a promising phytochemical used in the treatment of cancer. The current study is designed to review the different endoplasmic reticulum stress pathways involved in the cancer, mechanistic insights of luteolin as an anticancer agent in modulating ER stress, and the available luteolin patent formulations were also highlighted. The patents were selected on the basis of pre-clinical and/or clinical trials, and established antitumor effects using patent databases of FPO IP and Espacenet. The patented formulation of luteolin studied so far has shown promising anticancer potential against different cancer cell lines. However, further research is still required to determine the molecular targets of such bioactive molecules so that they can be used as anticancer drugs. 相似文献