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151.
A highly diastereoselective synthesis of heritol and heritonin by intramolecular cyclization on a preformed sensitive butenolide functionality is described. 相似文献
152.
Anirban Pal Dnyaneshwar Umrao Bawankule Mahendra Pandurang Darokar Subhash Chandra Gupta Jai Shankar Arya Karuna Shanker Madan Mohan Gupta Narayan Prasad Yadav Suman Preet Singh Khanuja 《Biomedical chromatography : BMC》2011,25(6):641-645
The influence of active fraction isolated from pods of an indigenous plant, Moringa oleifera (MoAF) was studied on the pharmacokinetic profile of the orally administered frontline anti‐tuberculosis drug rifampicin (20 mg/kg b.w.) in Swiss albino mice. The antibiotic rifampicin alone and in combination with MoAF (0.1 mg/kg b.w.) was administered orally and heparanized blood samples were collected from the orbital plexus of mice for plasma separation at 0, 1, 2, 3, 4 and 5 h, post treatment. Plasma rifampicin concentration, pharmacokinetic parameters and drug metabolizing enzyme (cytochrome P‐450) activity were determined. The pharmacokinetic data revealed that MoAF‐treated animals had significantly increased rifampicin plasma concentration, Cmax, Kel, t½(a), t½(el), Ka and AUC as well as inhibited rifampicin‐induced cytochrome P‐450 activity. In conclusion, the result of this study suggested that the bioavailability‐enhancing property of MoAF may help to lower the dosage level and shorten the treatment course of rifampicin. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
153.
A practical total synthesis of antidepressant (±)‐venlafaxine is disclosed. 相似文献
154.
Short and efficient synthesis of rubrolide E from commercially available 4‐methoxyacetophenone, employing ring‐closing metathesis, Knoevenagel condensation, and Reformatsky reactions, are the key steps are described. 相似文献
155.
Subhash Vaghani S. Vasanti Kiran Chaturvedi C. S. Satish S. J. Shankar 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(12):1015-1027
The aim of the present study was to prepare and evaluate microspheres of Eudragit (RS, RL and RSPO) containing an anticancer drug 5-FU. Microspheres were prepared by O/O solvent evaporation method using a acetone/liquid paraffin system. Magnesium stearate was used as the droplet stabilizer and n-hexane was added to harden the microspheres. The prepared microspheres were characterized for their micromeretic properties and entrapment efficiency; as well by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), X-ray powder diffractometry (XRPD), thin layer chromatography (TLC) and scanning electron microscopy (SEM) revealed the crystalline nature of drug in a final state. The in vitro release studies were performed in a Phosphate Buffer Solution (PBS) pH 7.4. The best fit release kinetics was achieved with a Higuchi plot. The yields of preparation and entrapment efficiencies were very high with a larger particle size for all the formulations. Mean particle size, entrapment efficiency and production yield were highly influenced by the type of polymer and polymer concentration. It is concluded from the present investigation that various Eudragit are promising controlled release carriers for 5-FU. 相似文献
156.
Subhash P. Chavan Lalit B. Khairnar Prakash N. ChavanNilesh B. Dumare Dinesh B. KalbhorRajesh G. Gonnade 《Tetrahedron letters》2014
The efficient and practical formal syntheses of both enantiomers of cis 3-hydroxypipecolic acid were accomplished from cis aziridine-2-carboxylate as the common synthetic precursor. The key steps involved are stereo and regioselective aziridine ring opening, reductive cyclization and selective N-debenzylation over O-debenzylation reactions. 相似文献
157.
This paper presents a new model for a special type of traveling salesman problem called the High Multiplicity Asymmetric Traveling Salesman Problem (HMATSP). The formulation adopts a flow-based subtour elimination structure and establishes its validity for this problem.
Also, we present computational results to demonstrate the efficacy of our modeling approach. The model is then incorporated
as a substructure in a formulation for the lot-sizing problem involving parallel machines and sequence-dependent setup costs,
also known as the Chesapeake Problem, and related test problems are solved to optimality for the first time in the literature. 相似文献
158.
Subhash J Bhatt 《Proceedings Mathematical Sciences》1986,95(2):97-107
A probability algebra (A, *, ω) consisting of a*algebraA with a faithful state ω provides a framework for an unbounded noncommutative probability theory. A characterization of symmetric probability algebra is obtained in terms of an unbounded strong commutant of the left regular representation ofA. Existence of coarse-graining is established for states that are absolutely continuous or continuous in the induced topology. Sufficiency of a*subalgebra relative to a family of states is discussed in terms of noncommutative Radon-Nikodym derivatives (a form of Halmos-Savage theorem), and is applied to couple of examples (including the canonical algebra of one degree of freedom for Heisenberg commutation relation) to obtain unbounded analogues of sufficiency results known in probability theory over a von Neumann algebra. 相似文献
159.
We obtain new results for manipulating and searching semi-dynamic planar convex hulls (subject to deletions only), and apply them to derive improved bounds for two problems in geometry and scheduling. The new convex hull results are logarithmic time bounds for set splitting and for finding a tangent when the two convex hulls are not linearly separated. Using these results, we solve the following two problems optimally inO(n logn) time: (1) [matching] givenn red points andn blue points in the plane, find a matching of red and blue points (by line segments) in which no two edges cross, and (2) [scheduling] givenn jobs with due dates, linear penalties for late completion, and a single machine on which to process them, find a schedule of jobs that minimizes the maximum penalty. 相似文献
160.
Subhash Bhatia 《Reaction Kinetics and Catalysis Letters》2005,84(2):295-302
Summary The catalytic cracking activity of mesoporous materials for the production of biofuel from fatty acid mixture is reported. AlMCM-41 synthesized was ion-exchanged with calcium ions and this material showed better hydrothermal stability but was less selective in the yield of gasoline fraction. Aluminium-containing LPMM-41 showed improved hydrothermal stability with the optimum yield of 43 wt.% gasoline fraction in the liquid hydrocarbon fuel product. 相似文献