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151.
Kumar Srivastava B Soni R Patel JZ Jha S Shedage SA Gandhi N Sairam KV Pawar V Sadhwani N Mitra P Jain MR Patel PR 《Bioorganic & medicinal chemistry letters》2008,18(14):3882-3886
Facile synthesis of biaryl pyrazole sulfonamide derivative of 5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxylic acid piperidin-1-ylamide (SR141716, 1) and an investigation of the effect of replacement of the –CO group in the compound 1 by the –SO2 group in the aminopiperidine region is reported. Primary ex-vivo pharmacological testing and in vitro screening of sulfonamide derivative 2 showed the loss of CB1 receptor antagonism. 相似文献
152.
Srivastava BK Soni R Joharapurkar A Sairam KV Patel JZ Goswami A Shedage SA Kar SS Salunke RP Gugale SB Dhawas A Kadam P Mishra B Sadhwani N Unadkat VB Mitra P Jain MR Patel PR 《Bioorganic & medicinal chemistry letters》2008,18(3):963-968
Design, synthesis and conformational analysis of few imidazole and oxazole as bioisosters of 4S-(-)-3-(4-chlorophenyl)-N-methyl-N'-[(4-chlorophenyl)-sulfonyl]-4-phenyl-4,5-dihydro-1H-pyrazole-1-caboxamidine (SLV-319) 2 is reported. Computer assisted conformational analysis gave a direct clue for the loss of CB1 antagonistic activity of the ligands without a fine docking simulation for the homology model. 相似文献
153.
Reaction of cis-Ru(bisox)2Cl2, where bisox is 4,4,4′,4′-tetramethyl-2,2′-bisoxazoline, with excess of pyridine-2-carboxaldehyde (py-2-al) in 1:1 (v/v) methanol-water mixture under nitrogen atmosphere and subsequent addition of excess of NH4PF6 give [Ru(bisox)2(py-2-al)](PF6)2 · H2O (1). Refluxing of 1 in dehydrated methanol in presence of triethylamine yields the corresponding hemiacetalate complex: [Ru(bisox)2 (pyridine-2-(α-methoxymethanolato))]PF6 · 1.5H2O (2). Both the complexes have been characterised by single crystal X-ray crystallography, FTIR and NMR. In cyclic voltammetry in acetonitrile at a glassy carbon electrode, 2 displays a quasireversible Ru(II/III) couple at 1.08 V versus NHE which is not observed in 1. A tentative mechanism is proposed for the conversion of 1 to 2. DFT calculations with the LanL2DZ basis set have been performed to investigate these observations theoretically. 相似文献
154.
Nematicidal prenylated flavanones from Phyllanthus niruri 总被引:1,自引:0,他引:1
Two prenylated flavanones have been isolated from the hexane extract of Phyllanthus niruri plant. The structure of these flavanones were established as 8-(3-Methyl-but-2-enyl)-2-phenyl chroman-4-one (1) and 2-(4-hydroxyphenyl)-8-(3-methyl-but-2-enyl)-chroman-4-one (2) on the basis of spectral analysis. These were evaluated for nematicidal activity against root-knot, Meloidogyne incognita, and reniform, Rotylenchulus reniformis, nematodes. Compound 2 exhibited nematicidal activity at par with the standard carbofuran (LC50 3.3 and 3.1ppm, respectively) when tested against reniform nematode. The LC50 value against root-knot nematode was found to be 14.5ppm. Compound 1 however, showed moderate activity against both the test nematodes. 相似文献
155.
Manfred T. Reetz Pankaj Soni Layla Fernández 《Biotechnology and bioengineering》2009,102(6):1712-1717
In rare but nevertheless important cases it is of practical interest to decrease the thermostability of an enzyme, that is, to increase thermolability in a controlled manner. In the present model study, this unconventional goal has been reached by applying directed evolution to the lipase from Pseudomonas aeruginosa (PAL). By utilizing the B‐factor iterative test (B‐FIT), previously developed to increase the thermostability of enzymes, it was possible to reduce the value from 71.6°C in the case of wild type (WT‐PAL) to 35.6°C (best mutant) without affecting the catalytic profile in terms of substrate acceptance or enantioselectivity at room temperature. Accordingly, saturation mutagenesis was performed at sites in PAL, which on the basis of its X‐ray structure, have the lowest B‐factors indicative of high rigidity. Focused mutations were introduced which can be expected to decrease rigidity, the ensuing increased flexibility leading to higher thermolability without changing the actual catalytic profile. Biotechnol. Bioeng. 2009;102: 1712–1717. © 2008 Wiley Periodicals, Inc. 相似文献
156.
Starting from previously reported cis-Ru(MeL)2Cl2, where MeL is 4,4,4′,4′-tetramethyl-2,2′-bisoxazoline, cis-Ru(MeL)2Br2 (1), cis-Ru(MeL)2I2 (2), cis-Ru(MeL)2(NCS)2 · H2O (3), cis-Ru(MeL)2(N3)2 (4) and cis-[Ru(MeL)2(MeCN)2](PF6)2 · (CH3)2CO (5) are synthesised. The X-ray crystal structures of complexes 1, 2, 3 and 5 have been determined. All the five new complexes have been characterized by FTIR, ESIMS and 1H NMR. In cyclic voltammetry in acetonitrile at a glassy carbon electrode, the complexes display a quasireversible Ru(II/III) couple in the range 0.32-1.71 V versus NHE. The Ru(II/III) potentials yield a satisfactorily linear correlation with Chatt’s ligand constants PL for the monodantate ligands. From the intercept and by comparing the known situation in Ru(2,2′-bipyridine)2L2, it is concluded that MeL, a non-aromatic diimine, is significantly more π-acidic than 2,2′-bipyridine. 相似文献
157.
Mukesh K. Malviya Anita Pandey Pankaj Trivedi Garima Gupta Bhavesh Kumar 《Current microbiology》2009,59(5):502-508
Seventy-eight isolates of actinomycetes were isolated from the soil samples collected from alpine zones of Pindari glacier
region in Indian Himalaya. Following a plate based rapid screening using two test fungi, five efficient isolates (nos. HA1,
HA2, HA6, HA40, and HA142) were selected for further characterization with special reference to their antagonistic properties.
Based on phenotypic and genotypic characters, the isolates were identified up to species level. All the isolates belonged
to the genus Streptomyces. The isolate nos. HA1 and HA2 were S. sampsonii and HA6, HA40 and HA142 were S. griseobrunneus, S. aurantiacus, and S. griseoluteus, respectively. The isolates showed strong antifungal properties against phytopathogenic test fungi in plate assays. All the
isolates hydrolyzed glycol–chitin as a substrate in denaturing conditions showing variable amount of different isoforms. 相似文献
158.
Govindan Selvakumar Piyush Joshi Pankaj K. Mishra Jaideep K. Bisht Hari S. Gupta 《Current microbiology》2009,59(4):432-438
Fourteen cold tolerant phosphate solubilizing bacteria isolated from high altitude representative locations of the two major
mountain aspects of the Uttarakhand Himalayas (cooler north and warmer south facing slopes) were selected for this study.
The tricalcium phosphate (TCP) solubilizing abilities of the isolates were estimated at three different incubation temperatures
viz., 4, 15, and 30°C under in vitro conditions. Irrespective of their geographical origin, all the isolates recorded maximum
P release values at 30°C. At 4°C, the isolates from the north facing slope were found to release significantly higher levels
of P, as compared to the isolates from the south facing slopes. Alternatively at 15°C, the isolates from the south facing
slope were found to release significantly higher levels of P. Initial confirmation of their genus level identity as Pseudomonads
was arrived by amplification of a 990 bp fragment of the 16S rRNA gene using genus specific primers. Further putative species
level identification was arrived by sequencing of the 16S rRNA gene. The diversity among the isolates was determined by rep-PCR
using the primers BOX, ERIC, and ERIC2. A composite dendrogram constructed using the rep-PCR profiles revealed that the isolates
from the north and south mountain aspects formed separate major clusters. The extent of diversity was greater among the isolates
from the south mountain aspect. This study reveals the potential of rep-PCR in determining the genetic diversity among Pseudomonads
selected for a single functional trait, but varying in their geographical origin. 相似文献
159.
Islam Md. Rashedul Trivedi Pankaj Palaniappan Pitchai Reddy M. S. Sa Tongmin 《World journal of microbiology & biotechnology》2009,25(6):1115-1117
The present study was undertaken to observe the effects of chemical fertilizers and compost amendments on microbial community
structure in rice based cropping system under long term fertilizer application experiment. Changes in microbial community
structure assessed by the relative abundance of fatty acid methyl ester (FAME) profiles revealed that compost amendments led
to promoting the abundance of Gram-positive bacterial FAMEs. Multivariate analysis of FAME profiles separated the treatments
primarily on the basis of the amount of added compost. A link between different fertilizer application treatment and soil
microbial components was tentatively established, but it needs to be verified in further studies. 相似文献
160.
Arvind Kumar Gupta Ashraf Yusuf Rangrez Pankaj Verma Anil Chatterji Yogesh S. Shouche 《Indian journal of microbiology》2009,49(2):169-187
Microbial communities in coastal subsurface sediments play an important role in biogeochemical cycles. In this study microbial
communities in tidal subsurface sediments of Balramgari in the state of Orissa, India were investigated using a culture independent
approach. Two 16S rDNA cloned libraries were prepared from the closely located (100 m along the coast) subsurface sediment
samples. Library I sediment samples had higher organic carbon content but lower sand percentage in comparison to Library II.
A total of 310 clone sequences were used for DOTUR analysis which revealed 51 unique phylotypes or operational taxonomic units
(OTUs) for both libraries. The OTUs were affiliated with 13 major lineages of domain bacteria including Proteobacteria (α, β, δ and λ), Acidobacteria, Actinobacteria, Cyanobacteria, Chloroflexi, Firmicutes, Verrucomicrobia, Bacteroidetes, Gemmatimonadetes and TM7. We encountered few pathogenic bacteria such as Aeromonas hydrophila and Ochrobactrum intermedium, in sediment from Library I. ∫-LIBSHUFF comparison depicts that the two libraries were significantly different communities.
Most of the OTUs from both libraries possessed ≥85% to <97% similarity to RDP database sequences depicting the putative presence
of new species, genera and phylum. This work revealed the complex and unique bacterial diversity from coastal habitat of Balramgari
and shows that, in coastal habitat a variability of physical and chemical parameter has a prominent impact on the microbial
community structure. 相似文献