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31.
Synthesis of 6‐Fluoro‐7‐cyclic Amino‐substituted Dicarboxylic Acid Quinolones and their Antibacterial Activity
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A. Ravi Kumar G. Sathaiah A. Chandra Shekhar K. Raju P. Shanthan Rao B. Narsaiah Y. Kanaka Raju U. S. N. Murthy V. Srimai M. Ramesh T. Parthasarathy 《Journal of heterocyclic chemistry》2014,51(Z1):E114-E122
Novel 1‐carboxymethyl‐6‐fluoro‐7‐cyclic amino‐substituted‐4‐oxo‐1,4‐dihydroquinolone‐3‐carboxylic acids 7a , 7b , 7c , 7d , 7e , 7f , 7g , 7h , 7i , 7j , 7k , 7l , 7m , 7n were synthesized as a new class of quinolones. Ethyl‐6‐fluoro‐7‐chloro‐1,4‐dihydro‐4‐quinoline‐3‐carboxylic acid was prepared from conventional method and reacted with ethyl bromoacetate to furnish N‐carboxymethyl derivatives. The compounds were screed against various Gram‐positive and Gram‐negative bacterial strains. Antibacterial activity data is validated by molecular docking studies. 相似文献
32.
Ji E Parthasarathy A Corbitt TS Schanze KS Whitten DG 《Langmuir : the ACS journal of surfaces and colloids》2011,27(17):10763-10769
Cationic poly(phenylene ethynylene)- (PPE-) based conjugated polyelectrolytes (CPEs) with six different chain lengths ranging in degree of polymerization from ~7 to ~49 were synthesized from organic-soluble precursor polymers. The molecular weight of the precursor polymers was controlled by the amount of a monofunctional "end-capping" agent added to the polymerization reaction. Cationic CPEs were prepared by quaternization of amine groups to tetraalkylammonium groups. Their structure-property relationships were investigated by observing their photophysical properties and antibacterial activity. The polymers were found to exhibit a chain-length dependence in their photophysical properties. It has also been observed that the polymers exhibit effective antibacterial activity against both Gram-positive and Gram-negative bacteria under UV irradiation, whereas they show little antibacterial activity in the dark. An effect of chain length on the light-activated antibacterial activity was also found: The shortest polymer (n=7) exhibited the most effective antibacterial activity against both Gram-positive and Gram-negative bacteria. 相似文献
33.
Karthikeyan J Parthasarathy K Cheng CH 《Chemical communications (Cambridge, England)》2011,47(37):10461-10463
A cobalt-catalyzed addition of aryl- and alkenylboronic acids to aldehydes and phthalaldehyde to give the corresponding biarylketones and 3-aryl phthalides in good to excellent yields in one pot is described. 相似文献
34.
Laser isotope separation (LIS) by infrared laser chemistry of polyatomic molecules has come a long way since its discovery.
The last decade has seen considerable efforts in scaling up of the process for light elements like carbon, oxygen and silicon.
These efforts aim at ways to improve both the enrichment factor and the throughput. The achievement is quite significant especially
for carbon isotope separation wherein macroscopic operating scales have been realized. We report our studies on the IR laser
chemistry of two promising systems, viz. neat CF2HCl and CF3Br/Cl2. We have investigated conditions for optimizing the dissociation yield and selectivity using natural samples containing l.l%C-13.Wealso
highlight our current efforts for scaling up the process. These include the design aspects of a photochemical reactor with
multipass refocusing Herriott optics for efficient photon utilization, development of a cryogenic distillation set up and
a preparative gas chromatograph for large scale separation/collection of the isotopically enriched photoproduct in the post-irradiation
stage. 相似文献
35.
36.
Experiments are described to measure the ultrasonic output from a quartz transducer by a calorimetric method. The electrical input power has also been estimated. The efficiency of conversion is examined in the light of available physical data for several liquids 相似文献
37.
Given a family of transition probability functions between measure spaces and an initial distribution Kolmogorov’s existence
theorem associates a unique Markov process on the product space. Here a canonical non-commutative analogue of this result
is established for families of completely positive maps betweenC* algebras satisfying the Chapman-Kolmogorov equations. This could be the starting point for a theory of quantum Markov processes.
Dedicated to the memory of Professor K G Ramanathan 相似文献
38.
The electrical resistivity of bulk Ge20Te80 has been measured as a function of pressure and temperature. At 5 GPa, an amorphous semiconductor-to-crystalline metal transition
has been observed. The sample recovered from the high pressure cell, after the application of 7 GPa, has a face-centred cubic
structure with a lattice constant of 6·42 A. In crystalline sample, the semiconductor-to-metal transition occurs at 7 GPa.
The thermoelectric power has also been measured for glassy samples in the temperature range 300–240 K. 相似文献
39.
40.
N-(17-methoxy-phenyl)-2-chloropyrrolo (2,3-b) quinoline was solved by direct methods and refined to anR of 0.104 for 950 observed reflections. The intensity data were collected by the multiple film equi-inclination Weissenberg
technique and estimated visually. The packing of the molecule is stabilised by van der Waals interaction. The pyrrolo (2,3-b) quinoline ring system is planar and the methoxy phenyl ring is approximately perpendicular to the plane of this ring system
with a dihedral angle of 86.5°. 相似文献