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111.
In the present article, using the Lie group of transformations technique all the invariant solutions of Einstein’s field equations for non-conformally flat perfect fluid spheres of embedding class one have been derived by considering a 5-flat space. The same problem for conformally flat case was tackled by Thakadiyil and Jasim (Int. J. Theor. Phys. 52:3960, 2013) using the same technique but with the lesser number of symmetries and hence could obtain only lesser number of solutions as compared to the number of solutions in this paper. All the solutions thus obtained have been subjected to reality conditions. As far as the authors are aware some of the solutions are new.  相似文献   
112.
Ultrasound was found to synergistically accelerate the condensation of phenol with β‐ketoesters in the presence of BiCl3. In the absence of ultrasound, under the same conditions, the reaction was found to be slow. Thus, the reaction can be carried out in the presence of ultrasound at room temperature (28–30°C), with a considerable reduction of reaction time, with high yield and high purity of coumarins.  相似文献   
113.
In the present article, we have found charged analogues of Henning Knutsen’s interior solutions which join smoothly to the Reissner–Nordstrom metric at the pressure free interface. The solutions are singularity free and analyzed numerically with respect to pressure, energy-density and charge-density in details. The solutions so obtained also present the generalization of A.L. Mehra’s solutions.  相似文献   
114.
Quinoxaline derivatives have been synthesized in excellent yields using an ionic liquid (IL) (viz., 1-n-butylimidazolium tetrafluoroborate) as a reaction medium as well as promoter from various 1,2-diketones and aryl-1,2-diamines. The process is general for the synthesis of quinoxaline derivatives from aromatic as well as aliphatic-1,2-diketones. The advantages of the present method are ambient reaction temperature, simplicity of operation, high yields of products, the recyclability of the IL, and ecofriendly nature of the reaction medium.  相似文献   
115.
A simple, efficient, and green protocol for synthesis of coumarin-3-carboxylic acids is described via Knoevenagel condensation of Meldrum's acid with ortho-hydroxyaryl aldehydes in [Hmim]Tfa ionic liquid, which was found to give better results than other ionic liquids. Furthermore, ionic liquid is easily reused without any appreciable loss in activity.  相似文献   
116.
Heteropoly acid tungstophosphoric acid (H3PW12O40) was found to be an excellent catalyst for the synthesis of symmetrical diaryl sulfoxides. The reaction was carried out in various organic solvents or ionic liquids and under solventfree condition. The reaction exhibited better results in terms of the yield and rate under solventfree condition. The catalyst was efficiently recovered from the reaction mixture and reused. The highlighting features of the present protocol are short reaction times, high yields of the products, ambient conditions, and simple workup.  相似文献   
117.
A simple and reliable method was developed for determining blood concentrations of tramiprosate using reversed‐phase HPLC with evaporative light scattering detection. The optimum evaporator and nebulizer temperatures for ELSD were set at 90 and 60°C respectively. The method was linear for a concentration range of 10–1000 µg/mL when 0.3 mL blood was used. The intra‐assay precision ranged from 1.84 to 5.24%, and the coefficient of variation (CV) for a quality control sample at 10 µg/mL was 5.24% with a bias of −9.50% from the target value. The inter‐assay precision ranged from 2.58 to 5.96%, and the CV for a quality control sample at 10 µg/mL was 5.96% with a bias of −7.50% from the target value. The method described here is suitable for management of tramiprosate in Alzheimer disease therapy. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
118.
Park JH  Bhilare SV  Youn SW 《Organic letters》2011,13(9):2228-2231
An NHC-catalyzed, regio- and stereoselective oxidative cyclization of o-alkynylbenzaldehydes bearing an unactivated alkyne moiety as an internal electrophile has been developed to afford phthalides and isocoumarins. A single organocatalytic system enabled two sequential C-O bond formations to take place in an atom economical manner via highly efficient dual activation. Molecular oxygen in air could be utilized as a source of an oxygen atom for the oxidation of aldehydes to the corresponding benzoic acids under our newly developed reagent system.  相似文献   
119.
120.
Coupling of acetyl acetone with diazotized 3-aminoacetophenone was carried out to give the compound 3. The compound was characterized by IR, 1HNMR, MS and elemental analysis. The X-ray analysis of 3 revels its planar nature with torsion angles between phenyl ring and acetyl group C2–C3–C7–O1 and C2–C3–C7–C8 of 177.8(3)° and ?0.9(4)°, respectively. Small deviations from planarity are evident also by torsion angles N1–N2–C9–C10 and N2–C9–C12–O3 of 176.6(2)° and 2.9(4)°, while the N2–C9–C10–O2 torsion angle with the value of ?165.2(3)° deviates from planarity. Hydrogen-bonded chain formed through C5–H5?O2 is connected with the adjacent antiparallel chain through C11–H11B···π interaction between the methyl group of the acetyl substituent and phenyl ring forming a double-layered chain. N1–N2 shows presence of single bond, showing it to be a hydrazone. Molecular docking study of the title compound with six members from CYP450 family shows encouraging activity.  相似文献   
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