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91.
The asymmetric synthesis of two well-known anti-depressant drugs, fluoxetine and duloxetine has been accomplished in a chemoenzymatic manner. The main highlight of the synthesis is the enantioselective cyanohydrin formation by a plant (R)-HNL (hydroxynitrile lyase). The enantiopure cyanohydrins are then synthetically manipulated into the above two drug molecules and two of their structural analogues, atomoxetine and nisoxetine. 相似文献
92.
93.
Biswarup Das Debashish Goswami Kalyan B. Sinha 《Communications in Mathematical Physics》2014,330(2):435-467
We give a new method for proving the homomorphic property of a quantum stochastic flow satisfying a quantum stochastic differential equation with unbounded coefficients, under some further hypotheses. As an application, we prove a Trotter product formula for quantum stochastic flows and obtain quantum stochastic dilations of a class of quantum dynamical semigroups generalizing results of Goswami et al. (Inst H Poincare Probab Stat 41:505–522, 2005). 相似文献
94.
Aza-Michael adducts are obtained in very good yields by the conjugate addition of aliphatic amines to α,β-unsaturated compounds using molecular iodine as catalyst in dichloromethane at room temperature. Aromatic amines were found to be reactive under reflux in toluene. 相似文献
95.
Vivek K. Gupta Corresponding author Pankaj Bandhoria Mohit Kalyan Manoj Mathews C. V. Yelamaggad 《Liquid crystals》2013,40(6):741-747
The crystal structure of cholesteryl 4‐[4‐(4‐n‐butylphenylethynyl)phenoxy]butanoate [phase sequence: Cr 155°C (46.1?J?g?1) SmA 186.8°C (1.5?J?g?1) TGB‐N* 204.7 (6?J?g?1) I] has been solved from single crystal X‐ray diffraction data. The compound crystallizes in the monoclinic space group P21 with unit cell parameters: a?=?13.129(2), b?=?9.3904(10), c?=?17.4121(8)?Å, β?=?92.790(7)°, Z?=?2. The structure has been solved by direct methods and refined to R?=?0.0606 for 3?250 observed reflections. The bond distances and angles are in good agreement with the corresponding values for compounds containing phenyl and cholesterol moieties. The phenyl rings A and B are planar. The dihedral angle between the least‐squares planes of the two phenyl rings is 28°. The cholesterol moiety has the usual structure: the C and E rings have chair conformations, and the D and F rings adopt half‐chair conformations. The molecules in the unit cell are arranged in an antiparallel manner. The crystal structure is stabilized by an intermolecular C–H…O contact of 2.989(10)?Å. 相似文献
96.
Abstract 3,6-Di-O-methyl-D-glucose, the non-reducing terminal sugar of the phenolic glycolipid-I, elaborated by Mycobacterium leprae, has been synthesized by a simple procedure and in high yield. 3-O-Methyl-D-glucose was converted to the corresponding benzyl glycoside and then tosylated to give benzyl 3-O-methyl-6-O-tosyl-β-D-glucopyranoside. Displacement of tosyl group with sodium methoxide followed by debenzylation afforded 3,6-di-O-methyl-D-glucose in high yield. Condensation of the acetobromo derivative of 3,6-di-O-methyl-D-glucose with 8-ethoxycarbonyloctanol gave 8-ethoxycarbonyloctyl 2,4-di-O-acety 1–3, 6-di-O-methy 1-β-D-glucopyranoside. This was then deacetylated, converted to hydrazide, and finally coupled to bovine serum albumin via the acyl azide intermediate. The neo-glycoprotein containing the 3,6-di-O-methyl-β-D-glucopyranosyl group is useful for serodiagnosis of leprosy. 相似文献
97.
Dr. Kalyan K. Sadhu Prof. Nicolas Winssinger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(25):8182-8189
Reactions templated by cellular nucleic acids are attractive for nucleic acid sensing or responsive systems. Herein we report the use of a photocatalyzed reductive cleavage of an immolative linker to unmask a rhodamine fluorophore, and its application to miRNA imaging. The reaction was found to proceed with a very high turnover (>4000) and provided reliable detection down to 5 pM of template by using γ‐serine‐modified peptide nucleic acid (PNA) probes. The reaction was used for the selective detection of miR‐21 in BT474 cells and miR‐31 in HeLa cells following irradiation for 30 min. The probes were introduced by using reversible permeation with streptolysin‐O (SLO) or a transfection technique. 相似文献
98.
E. Rajanarendar P. Ramesh E. Kalyan Rao A. Siva Rami Reddy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2555-2564
Isoxazolyl chloroacetamides (2) were obtained from 4-amino-3-methyl-5-styrylisoxazoles (1) on reaction with chloroacetyl chloride. Cyclocondensation of 2 with NH4SCN yielded 2([-methyl-5-(E)-2-aryl-1-ethenyl]-4-isoxazolylimino)-1,3-thiazolan-4-ones(3). Mannich reaction of 3 with formaldehyde and secondary amines gave isoxazolyl thiazolidinone Mannich bases (4 and 5). 相似文献
99.
K. Bhattacharjee C. K. Ghosh M. K. Mitra G. C. Das S. Mukherjee Kalyan Kumar Chattopadhyay 《Journal of nanoparticle research》2011,13(2):739-750
Nanocrystalline Ni
x
Zn1−x
Fe2O4 (0 ≤ x ≤ 1) ferrite powders with average particle size 15–20 nm have been successfully prepared at a very low temperature (180 °C)
by a novel auto combustion process using citric acid and ethylenediamine as a coordinating agent and bridging ligand, respectively.
Phase purity of the solid solutions has been confirmed by X-ray diffraction. Morphological characterizations of the prepared
samples were performed by high resolution transmission electron and field emission scanning electron microscopy. Extensive
Fourier transformed infrared spectroscopic characterization has been carried out to identify the plausible mechanism of the
synthesis process. Composition-dependent electrical properties (resistivity and dielectric constant) of the synthesized solid
solution have been investigated. Interestingly, a non-linear variation of dielectric permittivity with respect to composition
has been observed. The room temperature electrical resistivity as well as the dielectric permittivity of Ni0.5Zn0.5Fe2O4 was found to decrease with the decrease of particle size. 相似文献
100.
Large-scale organizations have used social computing platforms for various purposes. This research focuses on how hospitals utilize these platforms to attract potential customers (which represents the “extensivity” of a social computing platform) and generate interests in specific topics (which represents the “intensivity” of a platform). Specifically, we examine the effects of size of a hospital (or “size”) and the time that the social computing platform has been in existence (or “time”) on extensivity and intensivity. Our findings show that time is a significant variable on both dimensions; whereas size affects intensivity under certain conditions. We discuss the implications of these findings, and set the stage for future research. 相似文献