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181.
Padalkar VS Tathe A Gupta VD Patil VS Phatangare K Sekar N 《Journal of fluorescence》2012,22(1):311-322
Novel 2-(1H-benzimidazol-2-yl)-5-(N,N-diethylamino) phenol, 2-(1,3-benzoxazol-2-yl)-5-(N,N-diethylamino) phenol, 2-(1,3-benzothiazol-2-yl)-5-(N,N-diethylamino) phenol and their derivatives have been synthesized from p-N,N-diethyl amino salicylaldehyde with different substituted o-phenylenediamine or o-aminophenol or o-aminothiophenol and their photo-physical properties were studied. Effects of solvent polarity in the absorption-emission
properties of synthesized compounds were investigated. All these compounds shows excited state intra-molecular proton transfer
pathway having single absorption and dual emission characteristics. The fluorescent compounds were characterised by FT-IR,
1HNMR, 13C NMR and Mass spectral analysis. TGA analysis showed these compounds are thermally stable up to 200 °C. 相似文献
182.
Arvind G. Jangid Ashutosh M. Pudage Santosh S. Joshi Pramod N. Pabrekar Rajesh H. Tale Vikas V. Vaidya 《Biomedical chromatography : BMC》2010,24(7):727-731
A rapid, simple and specific method for estimation of anastrazole in human plasma was validated using letrozole as internal standard. The analyte and internal standard were extracted from plasma using simple solid‐phase extraction. The compound were separated on a reverse‐phase column with an isocratic mobile phase consisting of 0.1% formic acid in water and acetonitrile (12 : 88, v/v) and detected by tandem mass spectrometry in positive ion mode. The ion transitions recorded in multiple reaction monitoring mode were m/z 294.1 → 225.1 for anastrazole and m/z 286.1 → 217.1 for internal standard. Linearity in plasma was observed over the concentration range 0.3–30 ng/mL for anastrazole. The mean recovery for anastrazole was 83.7% with a lower limit of quantification of 0.3 ng/mL. The coefficient of variation of the assay was less than 6.8% and the accuracy was 96.1–102.2%. The validated method was applied to a bioequivalence study of 1 mg anastrazole tablet in healthy human volunteers. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
183.
A novel method for reduction of aromatic and heteroaromatic aldehydes with ammonium formate using Ni-nanoparticles is described. The Ni-nanoparticles act as a green catalyst for selective reduction of the aldehydic group in the presence of other functional groups, viz.: -NO2, -CN and alkenes to give the corresponding alcohols in excellent yields. 相似文献
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186.
On the mechanism of intramolecular nitrogen‐atom hopping in the carbon chain of C6N radical: A Plausible 3c−4e crossover
Long‐Bond
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Linear isomers of C6N radical differ in the position of the nitrogen atom in the carbon chain of C6N. Reaction routes, involving intramolecular nitrogen atom insertion at varying position in the carbon chain of C6N, are analyzed for the isomerisation between linear isomers of C6N. Through an automated and systematic search performed with global reaction route mapping of the potential energy surface, thermal isomerisation pathways for C6N radical are proposed based on the computations carried out at CASSCF/aug‐cc‐pVTZ, and CCSD(T)/6‐311++G(d,p)//B3LYP/6‐311++G(d,p) levels of the theory. Notably, a high lying linear isomer, centrosymmetric with respect to the nitrogen atom, is observed to be stabilized by a unique crossover three center‐four electron π long bond between the carbon atoms that are spatially separated by a nitrogen atom in a natural bond orbital. This long bond is concluded to be responsible for the predicted thermal isomerisation to be more feasible than the dissociation during the isomerisation pathway of a linear isomer of C6N. © 2014 Wiley Periodicals, Inc. 相似文献
187.
Srinivasarao Veedhi Vikas Mishra Sunil Kulkarni Rajasekhar Gorthi 《Journal of Thermal Analysis and Calorimetry》2014,115(1):909-914
Thermal instability is a loss of thermal control which liberates high amount of energy and pressure. An incident took place during drying of an intermediate having amino alcohol functional group in agitated nutsche filter dryer at plant scale. During our investigation using advanced reactive system screening tool (ARSST), thermal decomposition was observed. Onset temperature of decomposition (T o) is at 85 °C, adiabatic temperature rise due to decomposition (ΔT ad) is 215 °C, maximum temperature attained due to decomposition (T max) is 300 °C, maximum self-heat rate (dT/dt)max is 6,215 °C min?1, and maximum rate of pressure rise (dP/dt)max is 1,442 psi min?1 obtained from ARSST experiments. T D24 value is 75 °C which was estimated experimentally. The correlations of these results were utilized to identify the root cause of this incident and necessary control measures were taken accordingly. 相似文献
188.
Akshay Kumar Vivek SharmaJasneet Kaur Vikas KumarSuhel Mahajan Naveen KumarSwapandeep Singh Chimni 《Tetrahedron》2014
A highly enantioselective addition of diphenyl phosphite to ketimines derived from isatins has been developed employing bifunctional thiourea-tertiary amine organocatalysts. A variety of isatins derived ketimines react well with diphenyl phosphite in the presence of Cinchona-derived thiourea (epiCDT) to provide biologically important chiral 3-substituted 3-amino-2-oxindoles (3a–l) in good yield (up to 88%) and good enantioselectivity (up to 97% ee). The three-component version of the reaction through a domino aza-Wittig/phospha-Mannich sequence has successfully been explored. 相似文献
189.
Vikas Dubey Jagjeet Kaur N. S. Suryanarayana K. V. R. Murthy 《Research on Chemical Intermediates》2014,40(2):531-536
This paper reports TL glow curve analysis and evaluation of kinetic parameter for Amarnath stone collected from Amarnath Holy Cave. TL was recorded with different heating rates (3.3, 4, 6.7, 8, and 10 ° s?1). The samples gave good TL peaks at 310, 314, 308, 323, and 327 °C for the different heating rates. The corresponding activation energy (E) values were calculated. The peaks were indicative of second-order kinetics. Samples were characterized by XRD analysis. Inductively coupled plasma activated emission spectroscopic (ICP–AES) analysis was performed to determine percentages of elements in the natural mineral. Results from ICP–AES and XRF (X-ray fluorescence spectroscopy) studies were compared. 相似文献
190.
Jagjeet Kaur Deepti Singh Vikas Dubey N. S. Suryanarayana Yogita Parganiha Pooja Jha 《Research on Chemical Intermediates》2014,40(8):2737-2771
In this review different methods of preparing lanthanum aluminate (LaAlO3) phosphors are discussed. The molten salt method, the combustion method, the sucrose method, and the coprecipitation technique are the best methods for preparing LaAlO3 phosphors with small particle size and high surface area by low-temperature synthesis. LaAlO3 usually has a rhombohedral structure. It has good dielectric properties and, hence, is regarded as an attractive alternative to SiO2 in microelectronic devices. LaAlO3 phosphors have excellent chemical and thermal stability, mechanical durability, and exploitable optical and electronic properties, leading to a wide range of potential applications. LaAlO3 phosphors doped with rare-earth ions have luminescence properties and can, hence, be used in optical display systems. 相似文献