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51.
Dipti R. Patil Sonali M. Salunkhe Madhukar B. Deshmukh Prashant V. Anbhule 《Journal of heterocyclic chemistry》2011,48(6):1414-1418
A series of 2,3,4‐trisubstituted quinoline derivatives have been synthesized by reactions between 2‐aminoaryl ketones and dialkyl acetylenedicarboxylate. The synthetic pathway allows for the direct construction of said quinoline derivatives in pyridine/ethanol at ambient temperature through a zwitterion intermediate. J. Heterocyclic Chem., (2011) 相似文献
52.
53.
Ajeet A. Yelwande Madhukar E. Navgire Balasaheb R. Arbad Machhindra K. Lande 《中国化学会会志》2012,59(8):995-1000
Polyaniline/SiO2 nanocomposite material has been synthesized by using chemical oxidative method. Prepared catalytic material was characterized by means of transmission electron microscopy (TEM), thermal analysis (TG‐DTA), X‐ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Fourier transform infrared spectroscopy (FT‐IR). Solvent stability for the catalyst has been screened using UV‐Visible spectroscopy. Polyaniline/SiO2 catalyzed route has found to be an efficient and rapid protocol for the synthesis of quinoxaline derivatives by cyclocondensation of 1,2‐diketones and o‐phenylenediamines at room temperature. This protocol has several advantages such as high yield, good thermal stability, simple work up procedure, non‐toxic, clean, and easy recovery and reusability of the catalytic system. 相似文献
54.
G.R. Dillip S.J. Dhoble L. Manoj C. Madhukar Reddy B. Deva Prasad Raju 《Journal of luminescence》2012,132(11):3072-3076
Europium (III) ions doped red phosphors K4Ca(PO4)2 were prepared first time by high temperature solid state reaction method. The prepared phosphors structure was examined by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) analyses. The thermal properties of the synthesized phosphor were investigated by differential scanning calorimetry (DSC) analysis. Photoluminescence (PL) spectra of K4Ca(PO4)2:Eu3+ phosphors have shown strong red emission at 618 nm (5D0→7F2) with near UV an excitation wavelength of λexc=394 nm (7F0→5L6). In addition, the decay curves and CIE color coordinate measurements are also carried out. Hence, emission and excitation characterization of synthesized phosphors shows that the phosphors may be a promising red component for the application in the white light emitting diodes (WLEDs). 相似文献
55.
Madhukar Hemamalini Packianathan Thomas Muthiah Urszula Rychlewska Agnieszka Plutecka 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):o95-o97
In the title compound, C6H10N3+·HSO4−, the asymmetric unit consists of a hydrogen sulfate anion and a 2‐amino‐4,6‐dimethylpyrimidinium cation. The hydrogen sulfate anions self‐assemble through O—H⋯O hydrogen bonds, forming supramolecular chains along the b axis, while the organic cations form base pairs via N—H⋯N hydrogen bonds. The aminopyrimidinium cations join to the sulfate anions via a pair of hydrogen bonds donated from the pyrimidinium protonation site and from the exo amine group cis to the protonated site. 相似文献
56.
Raghunath B. Toche Bhausaheb K. Ghotekar Muddassar A. Kazi Madhukar N. Jachak 《Monatshefte für Chemie / Chemical Monthly》2009,15(1):235-241
Abstract
A novel method for the synthesis of 3-(2-substituted ethyl)-2-methylbenzohetero[3,2-a]pyrimidines in high yield (80–85%) was achieved, which involves a dihydrofuranone intermediate, readily obtained from β-ketolactone to 2-aminobenzoheterocycles. The major advantage of the methodology is the high yield and product purity. 相似文献57.
Madhukar N. Jachak Sandeep M. Bagul Dilip R. Birari Maruti G. Ghagare Muddassar A. Kazi Raghunath B. Toche Vijayavitthal T. Mathad 《Journal of fluorescence》2010,20(3):787-796
A rapid and efficient method for the synthesis of novel dipyrazolo[3,4-b:3′,4′-d]pyridines (DPP) from pyrazolo[3,4-b]pyridine was successfully developed. The DPP derivative was further N-alkylated (6, 8) as well as N-linked with amino acids (13) and their photophysical properties were studied along with N-aryl DPP 4 and observed that the chromophores at C4 position in the aryl ring changed the absorption and emission λmax. 相似文献
58.
Annamalai Subashini Madhukar Hemamalini P. Thomas Muthiah Gabriele Bocelli Andrea Cantoni 《Journal of chemical crystallography》2009,39(2):112-116
Abstract The structure of the title compound (C17H15N3O4S)2 the schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was elucidated by H1, C13 NMR, UV–VIS and IR spectroscopic techniques. The X-ray structure was determined in order to establish the conformation of
the molecule. The compound crystallizes in the triclinic space group P-1, with a = 11.419(1), b = 11.426(0), c = 13.316(1) ?, α = 71.94(2), β = 89.79(1), γ = 89.14(2)° and Z = 4. Two benzene rings and azomethine group are practically coplanar, as a result of intramolecular hydrogen bonds involving
the hydroxy O atom and azomethine N atom. The component species further interact via N–H···N and C–H···O hydrogen bonds and
π–π stacking interactions.
Index Abstract The title compound (C17H15N3O4S)2, Schiff base, bis(N-(5-methyl-3-isoxazolyl)-4-[(2-hydroxy benzylidene)-amino]) benzene sulfonamide was synthesized by the condensation of 4-amino-N-(5-methyl-3-isoxazolyl) benzene sulfonamide (SMZ) and 2-hydroxy benzaldehyde (SA). Its structure was confirmed by single
crystal X-ray diffraction analysis.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
59.
Madhukar S. Chande Rajgopal N. Dravid Nandita P. Shetgiri 《Journal of Chemical Sciences》1988,100(1):53-58
Interaction of ethyl chloroformate with γ-N-substituted trithioallophanic acids has been found to yield the corresponding
6-oxo-5-aryl-2,4-dithio-hexahydro-l,3,5-thiadiazines. These on reaction with amines yield 1,3,5-triazines. γ-N-substituted
β-oxo-dithio-allophanic acid with ethyl chloroformate similarly yields 4,6-dioxo-5-aryl-2-thio-1,3,5-thiadiazine. Antimicrobial
activity of thiadiazines has been reported. 相似文献
60.
Jadhav Sunetra J. Patil Reshma B. Kumbhar Digambar R. Patravale Ajinkya A. Chandam Dattatraya R. Deshmukh Madhukar B. 《Research on Chemical Intermediates》2017,43(4):2529-2543
Research on Chemical Intermediates - A series of novel 7-phenyl-7,12-dihydrobenzo(h)pyrido[2,3-b]naphthydrin-6(5H)-one were synthesized by a one-pot three-component condensation of... 相似文献