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81.
S.V. Kessar Y.P. Cupta T.V. Singh A. Sood A.K. Nanda K.R. Agnihotri 《Tetrahedron letters》1982,23(35):3619-3620
Photolysis of N-deuteriomethyl dihydroberberine salt (1b) gave 1-o-toluyl-3,4-dihydroisoquinoline (5b) with a deuterium atom incorporation; a mechanism involving a 1,7-hydrogen shift step is proposed. The keto-imine (5a) on irradiation followed by reduction furnished 11,12-dimethoxy tetrahydroberberine (9a). 相似文献
82.
Thin films of nanoporous tin oxide with a 3D face-centered orthorhombic nanostructure have been synthesized by self-assembly that is controlled by post-coating thermal treatment under controlled humidity. In contrast to the conventional evaporation-induced self-assembly (EISA), the films here have no ordered nanostructure after dip-coating. However, the initial coatings are formed under conditions that inhibit significant hydrolysis and condensation for extended periods. This allows the use of postsynthesis thermal vapor treatments to completely control the formation of the nanostructure. With EO106-PO70-EO106 (Pluronic F127) triblock copolymer as the template, highly ordered nanostructures were generated by exposing the disordered films to a stream of water vapor at elevated temperature, which rehydrates the films and allows the formation of the thermodynamically favored phase. Further exposure to water vapor drives the condensation reaction through the elimination of HCl. The X-ray diffraction pattern from the nanostructure was indexed in the space group Fmmm as determined by analysis of 2D small-angle X-ray scattering patterns at various angles of incidence. The nanostructure is then stabilized and made nanoporous by extended controlled thermal treatments. After self-assembly and template removal, the films are thermally stable up to 600 degrees C and retain an ordered, face-centered orthorhombic nanostructure. 相似文献
83.
84.
Shivani Sharma Ramdas S. Pathare Antim K. Maurya Bhagyashree Goswami Vijai K. Agnihotri Devesh M. Sawant Ram T. Pardasani 《Tetrahedron letters》2017,58(40):3823-3826
A metal-/oxidant-free sustainable protocol for the synthesis of 3-sulfenylindoles based on electrophilic cyclization of 2-alkynylanilines has been developed under microwave irradiation. Herein, catalytic amount of iodine and stoichiometric amount of sulfonyl hydrazides were employed as catalyst and electrophiles respectively to induce the 5-endo-dig cyclization of 2-alkynylanilines. This strategy allows a wide substrate scope, demonstrates good functional group tolerance, utilizes easily available reagents and overcome multistep synthesis. 相似文献
85.
Phenolic and flavonoid contents in leaf extracts of Bergenialigulata have been analysed for their contribution in antimicrobial and antioxidant activities. The extracts were prepared in three solvents (separately) following maceration and soxhelt methods. The antimicrobial activity was tested using disc diffusion assay against a range of microorganisms along with the determination of minimum inhibitory concentration (MIC), while the antioxidant activity was tested following DPPH assay. Leaf extracts exhibited antimicrobial activity against all the three groups of microorganisms; results coincided with respective MIC. In general, the methanol extracts prepared through maceration favoured the determination of antimicrobial and antioxidant activities. Maximum values for phenolic and flavonoid contents were obtained in macerated methanol and ethyl acetate extracts, respectively. The statistical correlations exhibited the extent of the contribution of phenolic and flavonoid contents in antimicrobial and antioxidant activities and also indicated the involvement of other plant metabolites. 相似文献
86.
K edge and its EXAFS for the Co++ ion in some double salts have been recorded. The white line is the only feature that is found to be characteristic of the double salts. 相似文献
87.
Thiourea Based Dipodal Receptor Development for Electrochemical Detection of Br− Ion in an Aqueous Medium 下载免费PDF全文
Narinder Singh Beant Kaur Billing Jasminder Singh Prabhat K. Agnihotri 《Electroanalysis》2016,28(4):718-723
Thiourea based dipodal receptor ( R1 ) was developed and characterised using 1H NMR, 13C NMR and mass spectroscopy. Using re‐precipitation method, R1 was processed into organic nanoparticles ( N1 ), evaluated its sensor activity in aqueous medium. The prepared N1 were characterized using Transmission Electron Microscopy (TEM) which shows 30 nm size. Dynamic Light Scattering (DLS) was employed for calculating average particle size. To imply N1 as sensor, its interaction with various anions was studied and found reasonable selectively for Br? ions with detection limit of 3.79 nM. For real life analysis, involving determining Br? from environmental samples, proposed sensor works successfully with accuracy more than 95 %. 相似文献
88.
Dixit Veena Irshad Saba Singh Harsh Agnihotri Priyanka Husain Tariq Khatoon Sayyada 《平面色谱法杂志一现代薄层色谱法》2017,30(1):25-31
JPC – Journal of Planar Chromatography – Modern TLC - This study was designed to develop a simple, sensitive, selective, and precise high-performance thin-layer chromatography (HPTLC)... 相似文献
89.
Aggarwal MM Agnihotri A Ahammed Z Angelis AL Antonenko V Arefiev V Astakhov V Avdeitchikov V Awes TC Baba PV Badyal SK Barlag C Bathe S Batiounia B Bernier T Bhalla KB Bhatia VS Blume C Bock R Bohne EM Böröcz Z Bucher D Buijs A Büsching H Carlen L Chalyshev V Chattopadhyay S Cherbatchev R Chujo T Claussen A Das AC Decowski MP Delagrange H Djordjadze V Donni P Doubovik I Dutt S Dutta Majumdar MR El Chenawi K Eliseev S Enosawa K Foka P Fokin S Ganti MS Garpman S Gavrishchuk O Geurts FJ Ghosh TK 《Physical review letters》2000,85(14):2895-2899
Three-particle correlations have been measured for identified pi(-) from central 158A GeV Pb+Pb collisions by the WA98 experiment at CERN. A substantial contribution of the genuine three-body correlation has been found as expected for a mainly chaotic and symmetric source. 相似文献
90.
A simple, rapid, highly sensitive and selective spectrophotometric method for the determination of tungsten(VI) in trace amounts is developed using 3-hydroxy-2-(2'-thienyl)-4-oxo-4H-1-benzopyran (HTB) as a reagent for the complexation of metal ion and extracting the 1:2 (metal:ligand) complex into dichloromethane from 0.2 M HCl solution. It obeys Beer's law in the range 0-2.8 microg Wml(-1) with molar absorptivity and Sandell's sensitivity at 415 nm as 6.45 x 10(4) L mol(-1) cm(-1) and 0.0029 microg W(VI) cm(-2), respectively. The method is free from the interference of a large number (39) of elements and handles satisfactorily the analysis of various samples of varying complexity. 相似文献