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61.
Girijesh Kumar Verma Gaurav ShuklaAnugula Nagaraju Abhijeet SrivastavaMaya Shankar Singh 《Tetrahedron》2014
An operationally simple and efficient one-pot straightforward method for the construction of 1,3-thiazolidin-4-ones has been developed by cyclocondensation of β-ketothioamides and an in situ generated acid anhydride from α-halocarboxylic acid in the presence of DCC at room temperature. The attractive features of this strategy include metal-free mild reaction conditions, short reaction time, and efficacy of forming consecutive C–S and C–N bonds and one ring in a single synthetic operation. Noteworthy, a Z-stereochemistry was observed for the exocyclic α-oxoketene moiety at 2-position of 1,3-thiazolidine ring. 相似文献
62.
63.
Radha Krishna Singamsetty Satish Kumar Vujjini Nagaraju Manne Brahmeshwara Rao Mandava Venkata Naga Vurimidi Himabindu Apurba Battacharya 《合成通讯》2013,43(24):4452-4459
A noninfringing synthesis of simvastatin 1, starting from lovastatin 2, is presented. This synthesis features the protection of the free hydroxyl group of the lovastatin with 3,4-dihydro-2H-pyran (DHP) and opening of the lactone ring with n-BuNH2 to afford amide 4 as a key intermediate. 相似文献
64.
2,6-Dichloropurine hydrochloride reacts with various types of alcohols using different alumina catalysts and converts into its N-9-alkyl-2-chloro-6-hydroxy-9H-purine products to an extent of 49–74%. The product selectivity depends on the stability of carbocation generated from the alcohol. More stable carbocation formulates both N-7 and N-9-alkyl-2,6-dichloropurine products, whereas the less stable carbocation results in exclusively N-9-alkyl-2-chloro-6-hydroxy-9H-purine. The catalytic activity of alumina prepared using the sol-gel method has larger Brunauer, Emmett, and Teller (BET) surface area and hence shows significantly greater catalytic activity than the commercially available alumina samples. 相似文献
65.
Ashok D. Nagaraju N. Lakshmi B. Vijaya Sarasija M. 《Russian Journal of General Chemistry》2019,89(9):1905-1910
Russian Journal of General Chemistry - In the present study, we report the synthesis of 5-[4-(3-phenyl-4,5-dihydro-1H-pyrazol-5-yl)phenyl]-1H-tetrazole derivatives by the Michael addition of... 相似文献
66.
Experimental study of dc and ac transport properties of CuInSe2/ZnO heterostructure is presented. The current-voltage (I-V) and frequency dependent capacitance (C-f) characteristics of CuInSe2/ZnO heterostructure were investigated in the temperature range 160-393 K. The heterostructure showed non-ideal behavior of I-V characteristics with an ideality factor of 3.0 at room temperature. Temperature dependent dc conductivity studies exhibited Arrhenius type behavior and revealed the presence of trap level. The C−2-V plot measured at frequency 50 kHz had shown non-linear behavior. An increase in capacitance with temperature was observed. The capacitance-frequency characteristics exhibited a transition between low frequency and the high frequency capacitance. As the temperature was lowered the transition occurred at lower frequencies. The frequency and temperature dependent device capacitance had shown a defect state having activation energy of 108 meV. 相似文献
67.
A capillary electrophoresis (CE) method is described for the simultaneous determination of copper and iron after complexation with a readily biodegradable chelating agent, [S,S']-ethylenediaminedisuccinic acid (EDDS), in wood pulp. CE separation was performed in a fused-silica capillary (50 microm i.d.; total length, 65 cm) with an electrolyte containing 25 mM borate buffer and 0.5 mM CTAB at pH 7.0 and an applied voltage of -25 kV. The samples were introduced by applying a 50 mbar pressure for 2 s, and detection of the complexes was monitored at 245 nm. The methodology performance of the methods was evaluated in terms of the linearity, limit of detection (LOD), limit of quantitation (LOQ) and reproducibility. The applicability of the method was demonstrated for the analysis of copper and iron in wood pulp. 相似文献
68.
CuIn1−xAlxSe2 (CIASe) thin films with x=0.25, 0.5 and 0.65 were prepared by four-source elemental evaporation. The structural and optical properties were investigated by X-ray diffraction, scanning electron microscopy, energy dispersive analysis, and optical transmission. The results showed that these films contain chalcopyrite structure with preferred orientation along (112) direction. The morphology, grain distribution and composition of CIASe films were studied and compared for different Al content. The optical studies revealed that the films were highly absorbing and the energy band gap calculated from transmission spectra for x=0.25, 0.5 and 0.65 were 1.2, 1.51 and 1.73 eV, respectively. The variation of Al content in the CIASe composition offered a very effective change in the optical band gap. 相似文献
69.
SK Hussain Balla Putrakumar Ponnala Bhanuchander Ginjupalli Srinivasarao Nekkala Nagaraju Koppadi Kumara Swamy Komandur V R Chary 《Catalysis Surveys from Asia》2022,26(2):104-114
Catalysis Surveys from Asia - Catalytic production of ethyl levulinate by alcoholysis of furfuryl alcohol with ethanol was investigated over H-mordenite supported Sn catalyst under atmospheric N2... 相似文献
70.
Manjunath Krishnappa Dr. Virgínia S. Souza Dr. Nagaraju Ganganagappa Dr. Jackson D. Scholten Prof. Sérgio R. Teixeira Prof. Jairton Dupont Dr. Ramakrishnappa Thippeswamy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(49):17624-17630
Hydrolysis of TiCl4 in a diether‐functionalized imidazolium ionic liquid (IL), namely 1‐methyl‐3‐[2‐(2‐methoxy(ethoxy)ethyl]imidazolium methane sulfonate (M(MEE)I ? CH3SO3), results in a heterostructured organic/inorganic and sponge‐like porous TiO2 material. The thermal treatment (300 °C) followed by calcination (500 °C) affords highly porous TiO2. The characterization of the obtained samples (with and without IL, before and after calcination) by XRD, SEM, and TEM reveals TiO2 anatase crystalline phases and irregular‐shaped particles with different porous structures. These hierarchical‐structured mesoporous TiO2 nanomaterials were employed as efficient photocatalysts in the water‐splitting process, yielding up to 1304 μmol g?1 on hydrogen production. 相似文献