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71.
Kulkarni CV Wachter W Iglesias-Salto G Engelskirchen S Ahualli S 《Physical chemistry chemical physics : PCCP》2011,13(8):3004-3021
During the last few years, there has been an extraordinary increase in publications describing the manifold applications of monoolein, one of the most important lipids in the fields of drug delivery, emulsion stabilization and protein crystallization. In this perspective we present a comprehensive review of the phase behavior of this 'magic lipid'. An account of various mesophases formed in the presence of water and a collection of formulae for the calculation of their nano-structural parameters are provided. Effects of chemical and biological molecules including lipids, detergents, salts, sugars, proteins and DNA on the classical behavior are also discussed. Physicochemical triggers such as, temperature, pressure and shearing modulate the phase behavior of monoolein self assemblies that are covered in subsequent sections. Finally the growing applications of monoolein in various fields are also reported. 相似文献
72.
N. Chandrashekhar V. Gayathri N. M. Nanje Gowda 《Magnetic resonance in chemistry : MRC》2009,47(8):666-673
Reactions of rhodium(III) halides with multidentate N,S‐heterocycles, (LH3) 1,3,5‐tris(benzimidazolyl)benzene (L1H3; 1 ), 1,3,5‐tris(N‐methylbenzimidazolyl) benzene (L2H3; 2 ) and 1,3,5‐tris(benzothiazolyl)benzene (L3H3; 3 ), in the molar ratio 1:1 in methanol–chloroform produced mononuclear cyclometallated products of the composition [RhX2(LH2)(H2O)] (X = Cl, Br, I; LH2 = L1H2, L2H2, L3H2). When the metal to ligand ( 1–3 or 1,2,4,5‐tetrakis(benzothiazolyl)benzene [L4H2; 4 ]) molar ratio was 2:1, the reactions yielded binuclear complexes of the compositions [Rh2Cl5(LH2)(H2O)3] (LH2 = L1H2, L2H2, L3H2) and [Rh2X4(L4)(H2O)2] (X = Cl, Br, I). Elemental analysis, IR and 1H nuclear magnetic resonance (NMR) chemical shifts supported the binuclear nature of the complexes. Cyclometallation was detected by conventional 13C NMR spectra that showed a doublet around ~190 ppm. Cyclometallation was also detected by gradient‐enhanced heteronuclear multiple bond correlation (g‐HMBC) experiment that showed cross‐peaks between the cyclometallated carbon and the central benzene ring protons of 1–3 . Cyclometallation was substantiated by two‐dimensional 1H? 1H correlated experiments (gradiant‐correlation spectroscopy and rotating frame Overhauser effect spectroscopy) and 1H? 13C single bond correlated two‐dimensional NMR experiments (gradient‐enhanced heteronuclear single quantum coherence). The 1H? 15N g‐HMBC experiment suggested the coordination of the heterocycles to the metal ion via tertiary nitrogen. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
73.
Rahul K. Suryawanshi Chandrashekhar D. Patil Hemant P. Borase Bipinchandra K. Salunke Satish V. Patil 《Applied biochemistry and biotechnology》2014,173(5):1209-1221
Efficacy of Serratia marcescens for pigment production and biological activity was investigated. Natural substrates like sweet potato, mahua flower extract (Madhuca latifolia L.), and sesam at different concentrations were taken. As a carbon source microorganism favored potato powder was followed by sesam and mannitol, and as nitrogen source casein hydrolysate was followed by yeast and malt extract. The effect of inorganic salts on pigment production was also studied. At final optimized composition of suitable carbon, nitrogen source, and trace materials and at suitable physiological conditions, prodigiosin production was 4.8 g L?1. The isolated pigment showed antimicrobial activity against different pathogenic bacteria and fungi. Extracted pigment was characterized by spectroscopy, Fourier transform infrared (FTIR), and thin layer chromatography (TLC) which confirm production of biological compound prodigiosin. This study suggests that use of sweet potato powder and casein can be a potential alternative bioresource for commercial production of pigment prodigiosin. 相似文献
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76.
Srinivas Gangula Chandrashekhar R. Elati Satish Varma Mudunuru Anitha Nardela Ashok Dongamanti Apurba Bhattacharya 《合成通讯》2013,43(15):2254-2268
Syntheses of all eight enantiomerically pure diastereomers of aprepitant and assignment of absolute configuration at newly generated stereocenters by NMR and x-ray crystallographic analysis were achieved. 相似文献
77.
Indresh Kumar Sravendra Rana Jae Whan Cho Chandrashekhar V. Rode 《Tetrahedron: Asymmetry》2010,21(3):352-355
The synthesis of a new class of hybrid 1,2,3-triazozlo-δ-lactams/lactones has been achieved using the Huisgen [3+2] dipolar cycloaddition ‘click-chemistry’ reaction of various organic azides with an activated alkyne in water, followed by cyclization. 相似文献
78.
An X-ray investigation of pure V2O3 in the temperature region 300 to 700 K has revealed the presence of more than one phase coexisting from ≈450 to at least 700 K. This observation can be correlated with the high temperature resistivity anomaly and with recent nmr studies on this material. 相似文献
79.
Naduvilpurakkal B. Shibin Radhakrishnan Sreekanth Usha K. Aravind Kadavilpparampu M. Afsal Mohammed Narayana V. Chandrashekhar Jayan Joseph Sisir K. Sarkar Devidas B. Naik Charuvila T. Aravindakumar 《Journal of Physical Organic Chemistry》2014,27(6):478-483
Free radical‐induced oxidation reactions of glucosamine naphthalene acetic acid (GNaa) and naphthalene acetic acid (Naa) have been studied using pulse radiolysis. GNaa was synthesized by covalently attaching Naa on glucosamine. Hydroxyl adduct (from the reaction of hydroxyl radicals (●OH) at the naphthalene ring) was identified as the major transient intermediate (suggesting that the ●OH reaction is on the naphthalene ring) and is characterized by its absorption maxima of 340 and 400 nm. Both GNaa and Naa undergo similar reaction pattern. The bimolecular rate constants determined for the reactions are 4.8 × 109 and 8.9 × 109 dm3 mol?1 s?1 for GNaa and Naa respectively. The mechanism of reaction of ●OH with GNaa was further confirmed using steady‐state method. Radical cation of GNaa was detected as an intermediate during the reaction of sulfate radical (SO4●?) with GNaa (k2 = 4.52 × 109 dm3 mol?1 s?1). This radical cation transforms to a ●OH adduct at higher pH. The radical cation of GNaa is comparatively long lived, and a cyclic transition state by neighboring group participation accounts for its stability. The oxy radical anion (O●?) reacts with GNaa (k2 = 1.12 × 109 dm3 mol?1 s?1) mainly by one‐electron transfer mechanism. The reduction potential values of Naa and GNaa were determined using cyclic voltammetric technique, and these are 1.39 V versus NHE for Naa and 1.60 V versus NHE for GNaa. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
80.
A detailed analysis of the infrared reflectivity spectra of the superionic conductors X β-aluminates (X = Na, K, Ag, Rb and Tl) is presented. A Kramers-Kronig analysis and the oscillator fits to the data have yielded the frequencies of the transverse optic and associated longitudinal optic modes. A model which ignores the coupling between the spinel blocks accounts for the number of observed infrared modes as well as the Raman modes. It is shown that even for the modes characteristic of the motions of the disordered X-ions, the wave vector selection rule is still valid. The results are discussed with the available theoretical calculations. 相似文献