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101.
Here, we report a new class of highly chemoselective reactions between squarate derivatives and the amino acid cysteine or unprotected peptides with a N-terminus cysteine that proceed most efficiently in entirely aqueous solution at neutral pH. Kinetic and structural studies reveal that the presence of hydrogen bonding in water is primarily responsible for both the high yield and fast rate of the reaction. 相似文献
102.
Summary Metal(II) complexes of 2-acetylthiophene-2-furoylhydrazone (HL) of the types [VO(HL)SO4], [Cu(HL)2Cl2(H2O)], [M(HL)2Cl2] [M=CoII, NiII, or ZnII] and [ML2(H2O)2] [M=CoII, NiII, CuII or ZnII] have been prepared and characterized on the basis of elemental analyses, molar conductance, magnetic susceptibility, visible, e.s.r. and i.r. spectral studies. The bonding and stereochemistry of the complexes are discussed. 相似文献
103.
Preeti Kaushik Ajit Kumar Prashant Kumar Sandeep Kumar Brajendra Kumar Singh 《合成通讯》2020,50(13):2033-2042
AbstractSynthesis of various symmetric and asymmetric 1,4-DHP linked 1,2,3-triazole derivatives from economical and readily available starting materials via a convenient methodology in a single-pot method using CuSO4·5H2O as an efficient catalyst has been reported. The reaction proceeded efficiently under the optimized reaction conditions with excellent functional group compatibility providing the desired products in good yields. The method appears to be an efficient combinatorial strategy for the synthesis of new 1,4-DHP linked triazole derivatives. 相似文献
104.
105.
Bhartiya Sushmita Singh Rashmi Singh Ashish Balal Mohammad Bhardwaj Preeti Kohli D. K. Singh M. K. 《Journal of Solid State Electrochemistry》2022,26(12):2829-2839
Journal of Solid State Electrochemistry - Nitrogen-doped mesoporous carbon aerogel having high surface area and high nitrogen content was synthesized by sol–gel method for supercapacitor... 相似文献
106.
Frontispiece: Glyceride‐Mimetic Prodrugs Incorporating Self‐Immolative Spacers Promote Lymphatic Transport,Avoid First‐Pass Metabolism,and Enhance Oral Bioavailability
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107.
The combined effect of microwave and RF oxygen plasma treatment of SiO2 surface on the hydrogen sensitivity of Pd gate MOS sensor has been studied. Nine different samples of thermally grown SiO2 surface have been taken and treated with oxygen plasma of different microwave power (100 W, 150 W and 200 W respectively) while keeping RF power fixed (20 W) for different durations (5 min, 10 min and 15 min). Pd gate MOS sensors with these plasma treated SiO2 surface as dielectric have been fabricated and tested for different concentrations (500–3500 ppm) of hydrogen at room temperature. It is observed that the sensitivity of the sensor increases for higher duration of plasma exposure and also with microwave power but decreases when the sensor is treated with 200 W microwave power for 10 min and 15 min durations. The sensor treated with oxygen plasma of 200 W microwave power for 5 min duration exhibited the highest hydrogen sensitivity (74.4%). Fixed oxide charge density has also been evaluated as a function of exposure time for varying microwave power. Surface morphology of plasma treated SiO2 surfaces was studied by AFM to have the estimation of porosity. The high sensitivity can be attributed to the fact that oxygen plasma treatment provides the availability of higher number of adsorption sites and modification in the surface state density i.e. surface state density increases for plasma treated sensors. 相似文献
108.
Han Y Cheng K Simon KA Lan Y Sejwal P Luk YY 《Journal of the American Chemical Society》2006,128(42):13913-13920
This work reports a new biocompatible surfactant structure, of which the hydrophilic head group is composed of a folded, stable self-inclusion complex of a ferrocenyl substituted beta-cyclodextrin (betaCD). While multiple intra- or intermolecular complexes can exist for this amphiphile, the molecule folds into a unique intramolecular complex with well-defined conformation, in which part of the aliphatic chain and the ferrocene group are both included in the annular cavity of betaCD. Study of different isosteric covalent linkages indicates that this folded structure is stable against displacement by the presence of other small guest molecules. Furthermore, in contrast to ferrocene-CD conjugates that are without the aliphatic chain, the presence of small guest molecules in solution does not influence at all the induced circular dichroism signal of this amphiphile, indicating a sterically congested, but stable, folded conformation of the inclusion complex. This new amphiphile is surface active and, more importantly, does not denature the membrane protein bacteriorhodopsin. Finally, because this surfactant forms self-assembled aggregates, this work introduces a folded structure into soft matters formed by amphiphiles in water. 相似文献
109.
Sasi Bhushan K. Rao Radhika M. Goswami Preeti G. Kannan S. 《Journal of Radioanalytical and Nuclear Chemistry》2020,323(3):1367-1372
Journal of Radioanalytical and Nuclear Chemistry - Alkali metaborate ions are usually monitored for the isotopic measurement of boron by positive thermal ionization mass spectrometry. Large... 相似文献
110.
A novel synthetic method for the synthesis of 1,2,4-triazoles have been described starting from 1,3,4-thiadiazoles by adsorbing on acidic alumina under microwave irradiations (MWI). 相似文献