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1.
J. D. Sudha Subrata Pradhan Heera Viswanath Jisha Unnikrishnan Priyanka Brahmbhatt M. S. Manju 《Journal of Thermal Analysis and Calorimetry》2014,115(1):743-750
Thermosetting blend system of co-cured cyanate ester with epoxy resin is receiving importance for high technological applications because of its wide range of thermo-mechanical, rheological, and electrical properties. However, processing of these system warrant proper knowledge of the rheological behavior of the blend during the curing process. This article discusses the rheological behavior of the blend systems with respect to the pot life, gel time, gelation temperature and also evaluated fitting parameters for the prediction of gelation time and viscosity during the entire curing process from the isothermal rheological measurements. 相似文献
2.
o-Lithio 2,3-; 3,4-; 3,5-; 2,5- and 2,4-dimethoxy-N-methyl-benzamides upon condensation with propylene oxide give corresponding
dimethoxy-3-methyl-3, 4-dihydroisocoumarins. The method has been used to synthesise (±)-6-methoxy mellein. 3-Methyl-6,7-dimethoxy-3,4-dihydroisocoumarin
has been synthesised by an acid catalysed cyclisation reaction. The dihydroisocoumarins have been dehydrogenated to respective
isocoumarins. 相似文献
3.
Sharma Deepak Sharma Naresh Brahmbhatt D. I. Gupta Vivek K. 《Crystallography Reports》2019,64(7):1047-1050
Crystallography Reports - The crystal structure of the title compound is determined by single crystal X-ray structure analysis. The structure was solved by direct method and refined to a final... 相似文献
4.
Keyur G. Brahmbhatt 《Tetrahedron letters》2009,50(39):5501-5504
Unprecedented aromatization was observed during N-alkylation reactions of 1-methyl-3,4-dihydro-β-carboline-3-carboxylic acid methyl ester, giving rise to 9-alkyl-1-methyl-β-carboline-3-carboxylic acid methyl esters. Inverse addition of base during a similar reaction resulted in a chemoselective alkylation to form novel 3-butyl-1-methyl-3,4-dihydro-β-carboline-3-carboxylic acid methyl ester as the major product in good yield. 相似文献
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1‐Acetyl‐ and 1‐propionyl‐2‐pyrazolines 11‐27 have been synthesized by the reaction of (3‐coumarinyl)chalcones 1‐10 with hydrazine in hot acetic acid or propionic acid. While 5‐aryl‐3‐(3‐coumarinyl)‐1‐phenyl‐2‐pyrazolines 28‐35 have been prepared by the reaction of (3‐coumarinyl)chalcones 1,3,5‐10 with phenylhydrazine in hot pyridine. Structures of all new compounds have been elucidated by microanalyses, 1H and 13C nmr spectroscopies. 相似文献
8.
Nafees Ahmed Keyur G. Brahmbhatt Inder P. Singh Kamlesh K. Bhutani 《Journal of heterocyclic chemistry》2011,48(1):237-240
Synthesis of various C‐3‐dialkyl derivatives of quinoline 2,4‐diol was achieved by condensation of aniline or substituted anilines with diethyl malonate, followed by chemoselective alkylation at C‐3 in water. The higher yields, easy work up and environmental compatible conditions are the main aspects of our method. J. Heterocyclic Chem., 2011. 相似文献
9.
Dinker I. Brahmbhatt Niraj H. Patel Anil K. Patel Mehul A. Patel Varun G. Patel 《Journal of heterocyclic chemistry》2011,48(4):840-844
The title compounds, 7‐aryl‐5,6‐dihydro‐14‐aza[1]benzopyrano[3,4‐b]phenanthren‐8H‐ones 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l have been synthesized by reacting various 4‐hydroxy coumarins 1a , 1b , 1c with 2‐arylidene‐1‐tetralones 2a , 2b , 2c , 2d in the presence of ammonium acetate and acetic acid under Krohnke's reaction condition. The structures of all the synthesized compounds were supported by analytical, IR, 1H‐NMR, and 13C‐NMR data. All the synthesized compounds 3a , 3b , 3c , 3d , 3e , 3f , 3g , 3h , 3i , 3j , 3k , 3l have been screened for their antibacterial activities against Escherichia coli (Gram ?ve bacteria), Bacillus subtilis (Gram +ve bacteria), and antifungal activity against Candida albicans (Fungi). J. Heterocyclic Chem., (2011). 相似文献
10.
Poly(anthranilic acid-formaldehyde)s (AFs) were prepared and characterized by IR spectroscopy, M– n, viscosity, and TGA. Polymeric metal chelates of AF samples with Cu2+, Co2+, Ni2+, Zn2+, Mn2+, and Cr2+ ions have been prepared and characterized. The electrical conductivity of polymeric chelates and iodine-doped polymeric chelates was studied over a temperature range of 35° to 100°C. From the electrical conductivity of these polymers, activation energies (Ea ) of electrical conduction were evaluated, and the electrical conductivity data of undoped and iodine-doped polymers were compared. 相似文献