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141.
Santosh M. Surwase Yogesh D. Mane Mahesh M. Surwase Bhimrao C. Khade 《Journal of heterocyclic chemistry》2020,57(2):724-730
A series of (E)-2-((1H-imidazol-1-yl)methyl)-2-((benzyloxy)methyl)-2,3-dihydro-1H-inden-1-one O-benzyl oximes ( 6a-j ) were prepared and evaluated for their in vitro antileishmanial potency against Leishmania donovani (in promastigote and amastigote models). At a concentration of 05-μg/mL, compounds 3a-d , 4a-d , 5a , 5b , 6a-d, and 7a-d exhibited 97% to 100% and 87% to 100% inhibition against promastigotes and amastigotes, respectively. Compounds 6a , 6d-6j and 6a , 6i , 6j exhibited equal antileishmanial potency to that of SSG and Pentamidin at lower values of IC50. 相似文献
142.
Kanchan Verma Yogesh Kumar Tailor Sarita Khandelwal Monu Agarwal Esha Rushell Sakshi Pathak Yogita Kumari Kamlendra Awasthi Mahendra Kumar 《应用有机金属化学》2020,34(10):e5836
An efficient and environmentally sustainable domino protocol has been presented for the synthesis of structurally diverse spiroannulated indolo[3,2-c]quinolines involving three component sequential reaction of phenylhydrazine, o-aminoacetophenone and cyclic ketones using nanostructured terbium doped TiO2 as recyclable and reusable heterogeneous catalyst. The nanostructured catalyst was synthesized successfully and characterized by X-ray Diffraction (XRD), transmission electron microscopy (TEM), EDX and Fourier transform infra-red spectroscopy (FTIR). The substitution of Ti+4 with Tb+3 and the formation of Ti-O-Tb bonds as a result of doping of Terbium with TiO2 NPs increases the catalytic efficiency and facilitates the reaction to provide the products in excellent yields. The present protocol with special features; operational simplicity, atom-economy, mild reaction conditions, environmental sustainability and high synthetic efficiency with recyclability and reusability of catalyst has been reported for the first time to synthesize spiroannulated indoloquinolines and expecting to provide the library of promising new leads in drug discovery research. 相似文献
143.
Nairn AK Archibald SJ Bhalla R Gilbert BC Maclean EJ Teat SJ Walton PH 《Dalton transactions (Cambridge, England : 2003)》2006,(1):172-176
Reaction of Cu(BF(4))(2).6H(2)O with the N(3)O(2) donor ligand H(2)L (where H(2)L = N-benzyl-N',N'-di-tert-butyl-disalicyl-triaminocyclohexane) results in the formation of a novel Cu(II)L complex, 1. X-Ray crystallography of it shows the Cu(II) centre coordinated by two phenolate oxygens and two imine nitrogens in a distorted square plane with an elongated bond to the amine nitrogen (2.512 A) in the axial position. EPR spectroscopy gives g values of g(1) = 2.277, g(2) = 2.100, g(3) = 2.025, and A(1) = 15.6 mT which are consistent with the distorted square pyramidal coordination environment determined from the X-ray structure. UV/visible and electrochemical analysis of shows that it undergoes two reversible processes assigned to the successive oxidation of the phenolate oxygens to phenoxyl radicals, the first at E((1/2)) = 0.89 V (DeltaE = 81 mV, vs. Ag/AgCl) and the second at E((1/2)) = 1.13V (DeltaE = 84 mV, vs. Ag/AgCl). Chemical oxidation results in the formation of a species, assigned as [1](+)(.) which is EPR silent due to antiferromagnetic coupling between the Cu(II) centre and the bound phenoxyl radical. The oxidised species catalyses the oxidation of benzyl alcohol to benzaldehyde. 相似文献
144.
An efficient and operationally simple strategy for the synthesis of differently C-3 monosubstituted (9) and disubstituted (10) monocyclic β-lactams is described. This involves reaction of β-lactam carbocation equivalents (8) with an active aromatic, aliphatic and heterocyclic substrates in the presence of a Lewis acid. 相似文献
145.
Microbial Fuel Cells: The Effects of Configurations,Electrolyte Solutions,and Electrode Materials on Power Generation 总被引:5,自引:0,他引:5
Fengxiang Li Yogesh Sharma Yu Lei Baikun Li Qixing Zhou 《Applied biochemistry and biotechnology》2010,160(1):168-181
This objective of this study is to conduct a systematic investigation of the effects of configurations, electrolyte solutions,
and electrode materials on the performance of microbial fuel cells (MFC). A comparison of voltage generation, power density,
and acclimation period of electrogenic bacteria was performed for a variety of MFCs. In terms of MFC configuration, membrane-less
two-chamber MFCs (ML-2CMFC) had lower internal resistance, shorter acclimation period, and higher voltage generation than
the conventional two-chamber MFCs (2CMFC). In terms of anode solutions (as electron donors), the two-chamber MFCs fed with
anaerobic treated wastewater (AF-2CMFCs) had the power density 19 times as the two-chamber MFCs fed with acetate (NO3
−2CMFCs). In terms of cathode solutions (as electron acceptors), AF-2CMFCs with ferricyanide had higher voltage generation
than that of ML-2CMFCs with nitrate (NO3
−ML-2CMFCs). In terms of electrode materials, ML-2CMFCs with granular-activated carbon as the electrode (GAC-ML-2CMFCs) had
a power density 2.5 times as ML-2CMFCs with carbon cloth as the electrode. GAC-ML-2CMFCs had the highest columbic efficiency
and power output among all the MFCs tested, indicating that the high surface area of GAC facilitate the biofilm formation,
accelerate the degradation of organic substrates, and improve power generation. 相似文献
146.
Anil K. Patel Jayesh J. Ahire Shrikant P. Pawar Bhushan L. Chaudhari Yogesh S. Shouche Sudhir Bhaskarrao Chincholkar 《Applied biochemistry and biotechnology》2010,160(1):140-155
Siderophoregenic Bacillus strain DET9 has been selectively isolated from dairy waste. It was evaluated for probiotic characteristics and susceptibility
pattern against antibiotics. Its spores showed excellent tolerance to simulated gastrointestinal tract conditions and exhibited
antimicrobial activity against organisms such as Escherichia coli, Micrococcus flavus, and Staphylococcus aureus. Its susceptibility to antibiotics reduces the prospect to donate resistance determinants if administered in the form of probiotic
preparations. It was observed to produce ∼60 mg/l catecholate type of siderophore under iron stressed conditions, identified
as a 2,3-dihydroxy benzoic acid by high-performance liquid chromatography, infrared spectroscopy, nuclear magnetic resonance,
and mass spectral analysis. Partial 16S-rRNA gene sequencing analysis shows that the isolate exhibited homology with Bacillus thuringiensis and Bacillus weihenstephanensis, whereas biochemical characterization revealed its novelty. DET9 exhibited no mortality of fishes in a 60-day trial, when
fishes (surfi tetra) were challenged up to 100 ppm cell concentration, with their daily diet. 相似文献
147.
Ashraf Y Rangrez Mohammad Y Abajy Walter Keller Yogesh Shouche Elisabeth Grohmann 《BMC biochemistry》2010,11(1):10
Background
Type four secretion systems (TFSS) are bacterial macromolecular transport systems responsible for transfer of various substrates such as proteins, DNA or protein-DNA complexes. TFSSs encode two or three ATPases generating energy for the secretion process. These enzymes exhibit highest sequence conservation among type four secretion components. 相似文献148.
UV-initiated photo-modification by hydrophilic functional moieties (viz. acrylic acid, acrylamide) is performed on the photo-responsive Polyether sulfone (PES) membrane. Characterization of the modified membranes has been done by porometry, Fourier Transform-IR (FTIR), contact angle, thermogravimetry, X-ray diffraction and gel permeation chromatography. The grafting of acrylamide is higher compared to acrylic acid, as is evidenced from weight increase, as well as porometry studies. The separation abilities of Bovine Serum Albumin (BSA) have been experimented through all the membranes and results show that modified membranes possess a better separation ability compared to virgin polyether sulfone. The separation order follows the trend: PES-g-(AM) > PES-g-(AA) > PES. pH dependence conformational changes of BSA macromolecule influence the separation. The increase in pH results in the decreasing trend in separation. The water flux recovery ratio (FRR) for the virgin PES membrane is minimum compared to other two grafted membranes. 相似文献
149.
Bediako DK Lassalle-Kaiser B Surendranath Y Yano J Yachandra VK Nocera DG 《Journal of the American Chemical Society》2012,134(15):6801-6809
An oxygen evolution catalyst that forms as a thin film from Ni(aq)(2+) solutions containing borate electrolyte (Ni-B(i)) has been studied by in situ X-ray absorption spectroscopy. A dramatic increase in catalytic rate, induced by anodic activation of the electrodeposited films, is accompanied by structure and oxidation state changes. Coulometric measurements correlated with X-ray absorption near-edge structure spectra of the active catalyst show that the nickel centers in activated films possess an average oxidation state of +3.6, indicating that a substantial proportion of nickel centers exist in a formal oxidation state of Ni(IV). In contrast, nickel centers in nonactivated films exist predominantly as Ni(III). Extended X-ray absorption fine structure reveals that activated catalyst films comprise bis-oxo/hydroxo-bridged nickel centers organized into sheets of edge-sharing NiO(6) octahedra. Diminished long-range ordering in catalyst films is due to their ostensibly amorphous nature. Nonactivated films display a similar oxidic nature but exhibit a distortion in the local coordination geometry about nickel centers, characteristic of Jahn-Teller distorted Ni(III) centers. Our findings indicate that the increase in catalytic activity of films is accompanied by changes in oxidation state and structure that are reminiscent of those observed for conversion of β-NiOOH to γ-NiOOH and consequently challenge the long-held notion that the β-NiOOH phase is a more efficient oxygen-evolving catalyst. 相似文献
150.
A new fluorescent chemosensor based on the calix[4]arene of partial cone conformation possessing a dansyl moiety has been synthesized. The chemosensor demonstrates selective optical recognition of Hg(2+) and Cu(2+) in two contrasting modes. The receptor exhibited ratiometric sensing of Hg(2+) and "ON-OFF" type of fluorescence behavior in the presence of Cu(2+). The compound behaves as a fluorescent molecular switch upon chemical inputs of Hg(2+) and Cu(2+) ions. 相似文献