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排序方式: 共有234条查询结果,搜索用时 15 毫秒
111.
Dash J Das RN Hegde N Pantoş GD Shirude PS Balasubramanian S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(2):554-564
The design and synthesis of a series of bis‐indole carboxamides with varying amine containing side chains as G‐quadruplex DNA stabilising small molecules are reported. Their interactions with quadruplexes have been evaluated by means of Förster resonance energy transfer (FRET) melting analysis, UV/Vis spectroscopy, circular dichroism spectroscopy and molecular modelling studies. FRET analysis indicates that these ligands exhibit significant selectivity for quadruplex over duplex DNA, and the position of the carboxamide side chains is of paramount importance in G‐quadruplex stabilisation. UV/Vis titration studies reveal that bis‐indole ligands bind tightly to quadruplexes and show a three‐ to fivefold preference for c‐kit2 over h‐telo quadruplex DNA. CD studies revealed that bis‐indole carboxamide with a central pyridine ring induces the formation of a single, antiparallel, conformation of the h‐telo quadruplex in the presence and absence of added salt. The chirality of h‐telo quadruplex was transferred to the achiral ligand (induced CD) and the formation of a preferred atropisomer was observed. 相似文献
112.
Nalawade Pravin Aware Babasaheb Dand Neha Kadam Vilasrao Hirlekar Rajashree 《Journal of inclusion phenomena and macrocyclic chemistry》2009,65(3-4):377-383
In this work, we illustrate the usefulness of cyclodextrins, namely, methyl-β-cyclodextrin (MβCD), an amorphous, methylated derivative of the natural β-cyclodextrin, as a tool to form an inclusion complex with Valsartan (VAL), a poorly water soluble drug. The phase solubility study showed AL type of curve with slope less than one indicating the formation of complexes in 1:1 molar ratio of drug and CD. The stability constant was found to be 538.14 ± 5.4 Mole?1. Solid binary systems between VAL and MβCD were prepared experimentally in a stoichiometry 1:1 by different techniques (physical mixing, kneading, co-evaporation). Afterward these products were characterized by Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimetry (DSC), Scanning electron microscopy (SEM) and 1H Nuclear magnetic resonance study (1H NMR). The results obtained suggested that co-evaporation methods yield a higher degree of amorphous entities suggesting the formation of inclusion complex between VAL and MβCD. The dissolution of VAL from the binary systems was studied to select the most appropriate system for the formulation development. It was concluded that the preparation technique played an important role in the dissolution behavior of the drug and the inclusion complex between VAL and MβCD obtained by co-evaporation method allowed better performance. 相似文献
113.
Amol H. Kategaonkar Vilas B. Labade Pravin V. Shinde Atul H. Kategaonkar Bapurao B. Shingate Murlidhar S. Shingare 《Monatshefte für Chemie / Chemical Monthly》2010,46(6):787-791
Abstract
A series of new tetrazolo[1,5-a]quinoline-4-carbonitrile derivatives were synthesized for the first time via tetrazolo[1,5-a]quinoline derivatives. Elemental analysis, IR, 1H NMR, 13C NMR, and mass spectral data were used to elucidate the structures of all newly synthesized compounds. In vitro antimicrobial activities of synthesized compounds were investigated against Gram-positive Bacillus subtilis, Gram-negative Escherichia coli, and two fungi, Candida albicans and Aspergillus niger, in comparison with standard drugs. Some of the tested compounds showed significant antimicrobial activity. 相似文献114.
The sesquiterpene fraction of Annona reticulata bark was studied by GC/MS. Three major components were identified: copaene (35.40%), patchoulane (13.49%) and 1H-cycloprop(e)azulene (22.77%). The fraction was also screened for its analgesic and anti-inflammatory activities. The sesquiterpene fraction at doses 12.5 and 25?mg?kg?1 and the unsaponified petroleum ether extract at a dose of 50?mg?kg?1 exhibited significant central as well as peripheral analgesic and anti-inflammatory activities. These activities were comparable with the standard drugs used in the respective experiments. 相似文献
115.
Sawanta S. Mali Pravin S. Shinde Chirayath A. Betty Popatrao N. Bhosale Young Woo Oh Pramod S. Patil 《Journal of Physics and Chemistry of Solids》2012,73(6):735-740
Semiconducting Cu2ZnSnS4 (CZTS) material has been receiving a great technological interest in the photovoltaic industry because of its low-cost non-toxic constituents, ideal direct band gap as a absorber layer and high absorption coefficient. CZTS thin films have been successfully deposited onto the fluorine-doped tin oxide/glass (glass/FTO) substrates coated glass substrates using successive ionic layer adsorption and reaction (SILAR) method and investigated for photoelectrochemical conversion (PEC) of light into electricity. The best solar cell sample showed an open-circuit voltage of 390 mV, a short-circuit current density of 636.9 μA/cm2, a fill factor of 0.62 and an efficiency of 0.396% under irradiation of 30 mW/cm2. Preliminary results obtained for solar cells fabricated with this material are promising. 相似文献
116.
A one pot, three-component condensation of benzoin/benzyl, an aldehyde, and ammonium acetate using diethyl bromophosphate as a mild oxidant is achieved to form trisubstituted imidazole compounds. Under ultrasound irradiation, a smooth condensation occurs to get the 2, 4, 5-triaryl-1H-imidazole compounds in good to excellent yields. The study explores the scope and limitation of diethyl bromophosphate as an oxidant and suggests advantages, viz., simplicity of operation, reduction in time, and an increase in product yields. 相似文献
117.
118.
Pravin Chavan Amol Salve Shivaji Jadhav Dattatraya Pansare Megha Rai 《Journal of heterocyclic chemistry》2020,57(3):1228-1235
In this study, new series of azetidine derivatives were synthesized ( 4a-n ) from isoniazide ( 1 ), Aromatic aldehydes ( 2a-n ), dihydropyran ( 3 ) using SnCl2 catalyst, via one pot multicomponent reaction/cycloaddition reaction. The synthesized azetidine derivatives were characterized by IR, 1H NMR and 13C NMR and have been screened for antimicrobial, antituberculosis and anti-inflammatory activities. In relation to Staphylococcus aureus (ATCC 25923) promising antibacterial activity was shown, compounds 4e and 4k , followed by compounds 4h , 4n , 4f , 4g and 4l . The synthesized azetidine derivatives, 4a , 4e , 4j and 4m (with zone 12 mm) displayed antituberculosis activity. But its lower potential than, the standard streptomycin (with zone 18 mm). Further 4d compound alone displayed similar activity. 相似文献
119.
Ramesh Paudel Gopi Chandra Kaphle Mohammed Batouche Jingchuan Zhu 《International journal of quantum chemistry》2020,120(24):e26417
The half-metallicity of Heusler alloys is quite sensitive to high pressure and disorder. To understand this phenomenon better, we systematically studied the half-metallic nature, magnetism, phonon, and thermomechanical properties of FeCrTe and FeCrSe Heusler alloys under high pressure using ab initio calculations based on density functional theory. The ground-state lattice constants for FeCrTe and FeCrSe alloys are 5.93 and 5.57 Å, respectively, consistent with available theoretical results. Formation energy, cohesive energy, elastic constants, and phonon dispersion confirmed that both compounds are thermodynamically and mechanically stable. The FeCrTe and FeCrSe alloys showed a half-metallic character with a band gap of 0.68 and 0.58 eV at 0 GPa pressure, respectively, and magnetic moments of 2.01 μB for both alloys, using generalized gradient approximation (GGA) approximation. FeCrTe alloy changes from metallic to half-metallic above 30 GPa pressure using GGA + U. The elastic properties were scrutinized, and it was found that, at 0 GPa pressure, FeCrTe is ductile, and FeCrSe is brittle. Under pressure, FeCrSe becomes brittle above 10 GPa pressure. Average sound velocity Vm, Debye temperature ƟD, and heat capacity CV were predicted under pressure. These outcomes will improve the integration of Fe-based half-Heusler alloys in spintronic devices. 相似文献
120.
Prashant P. Thakare Yogesh Walunj Abhijit Chavan Vivek D. Bobade Dhiman Sarkar Pravin C. Mhaske 《Journal of heterocyclic chemistry》2020,57(11):3918-3929
A new series of 4-(4-(1-benzyl-1H-1,2,3-triazol-4-yl)-1-phenyl-1H-pyrazol-3-yl)quinoline ( 6a-t ) have been synthesized by a click reaction of 4-(4-ethynyl-1-phenyl-1H-pyrazol-3-yl)quinoline ( 4a-d ) with a substituted benzyl azide ( 5a-e ). The starting alkyne derivatives 4a-d are obtained from Bestmann-Ohira reaction of 1-phenyl-3-(quinolin-4-yl)-1H-pyrazole-4-carbaldehyde and dimethyl(1-diazo-2-oxopropyl)phosphonate. The newly synthesized compounds are screened against M. tuberculosis H37Ra dormant and active, Escherichia coli, Pseudomonas fluorescence, Staphylococcus aureus and Bacillus subtilis strains at 30 μg/mL concentration. Most of the screened compounds showed good to moderate antibacterial activity against S. aureus, B. subtilis, and Mycobacterium tuberculosis H37Ra strains. The synthesized derivatives of quinolinyl-pyrazole-4-carbaldehyde and quinolinyl-pyrazole-4-ethyne reportd good to moderate activity against both strains of M. tuberculosis H37Ra. Ten derivatives of quinolinyl-pyrazole presented good activity against B. subtilis. These results suggested that further optimization and development of quinolinyl-pyrazolyl-1,2,3-triazole moeity could serve as lead compounds for antimycobacterial activity. 相似文献