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排序方式: 共有1423条查询结果,搜索用时 16 毫秒
1.
In this article, we have studied the bound anionic states of DNA and RNA nucleobases using the newly developed bt-PNO-EOM-CCSD method and extended basis sets. All of the five nucleobases have a single bound anionic state, which is dipole bound in nature. The electron affinity corresponding to the dipole-bound state is found to be extremely sensitive to the used basis set, and a proper agreement with the available experimental data requires a large basis set with a sufficient number of diffuse functions. Electron correlation plays a major role in stabilizing the bound anionic states of nucleobases. No valence-bound anionic states are observed for any of the nucleobases. 相似文献
2.
Vishal Kandathil Aisha Siddiqa Abhinandan Patra Bhakti Kulkarni Manjunatha Kempasiddaiah B.S. Sasidhar Shivaputra A. Patil Chandra Sekhar Rout Siddappa A. Patil 《应用有机金属化学》2020,34(11):e5924
N-heterocyclic carbene (NHC)-palladium(II) complex (GO@NHC-Pd) was synthesized on graphene oxide (GO) support via a simple and cost-effective multistep approach. The spectroscopic, microscopic, thermal, and surface analyses of GO@NHC-Pd confirmed the successful formation of the catalyst. The investigation of catalytic activity showed that GO@NHC-Pd was very effective in Suzuki–Miyaura as well as Hiyama cross-coupling. Being heterogeneous in nature, GO@NHC-Pd was recovered after each reaction cycle easily and reused for up to nine and six cycles in Suzuki–Miyaura and Hiyama cross-coupling, respectively, without significant loss of activity. Further exploration of the supercapacitor performance of GO@NHC-Pd catalyst assembled in a two-electrode cell configuration shown a maximum attained capacitance of 105.26 F/g at a current density of 0.1 A/g with good cycling stability of 96.89% over 2,500 cycles. 相似文献
3.
Rahul S. Patil Dr. Debasis Banerjee Cory M. Simon Prof. Jerry L. Atwood Dr. Praveen K. Thallapally 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12618-12623
Separation of xenon and krypton is of industrial and environmental concern; the existing technologies use cryogenic distillation. Thus, a cost‐effective, alternative technology for the separation of Xe and Kr and their capture from air is of significant importance. Herein, we report the selective Xe uptake in a crystalline porous organic oligomeric molecule, noria, and its structural analogue, PgC‐noria, under ambient conditions. The selectivity of noria towards Xe arises from its tailored pore size and small cavities, which allows a directed non‐bonding interaction of Xe atoms with a large number of carbon atoms of the noria molecular wheel in a confined space. 相似文献
4.
Gold(I)/Chiral Brønsted Acid Catalyzed Enantioselective Hydroamination–Hydroarylation of Alkynes: The Effect of a Remote Hydroxyl Group on the Reactivity and Enantioselectivity 下载免费PDF全文
Valmik S. Shinde Manoj V. Mane Dr. Kumar Vanka Arijit Mallick Dr. Nitin T. Patil 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):975-979
The catalytic enantioselective hydroamination–hydroarylation of alkynes under the catalysis of (R3P)AuMe/(S)‐3,3′‐bis(2,4,6‐triisopropylphenyl)‐1,1′‐binaphthyl‐2,2′‐diyl hydrogenphosphate ((S)‐TRIP) is reported. The alkyne was reacted with a range of pyrrole‐based aromatic amines to give pyrrole‐embedded aza‐heterocyclic scaffolds bearing a quaternary carbon center. The presence of a hydroxyl group in the alkyne tether turned out to be very crucial for obtaining products in high yields and enantioselectivities. The mechanism of enantioinduction was established by carefully performing experimental and computational studies. 相似文献
5.
Rane Vipul P. Patil Rushikesh H. Patil Kiran R. Pathan Amin R. Naik Sukantakumar Ahirrao Vinod K. Jadhav Rajiv A. Yeole Ravindra D. 《Chromatographia》2022,85(2):155-165
Chromatographia - WCK 771 is a novel antibacterial drug recently launched in India for the treatment of acute bacterial skin and skin structure infections (ABSSSI). This report describes... 相似文献
6.
Kiran Patil Amin Pathan Sukanta Naik Vineet Zope Rajesh Chavan Ravindra Yeole 《Biomedical chromatography : BMC》2022,36(7):e5377
A precise and accurate liquid chromatography–tandem mass spectrometric (LC–MS/MS) bioanalytical method has been developed and validated for the simultaneous quantification of WCK 4234 and meropenem (MEM) in dog plasma. Protein precipitation using acetonitrile was employed as a sample preparation approach. Cefepime was used as an internal standard. The developed method was selective, sensitive (limit of quantification, 0.075 μg/ml for both drugs), accurate (recovery > 90%), precise (CV < 10%) and linear (r2 ≥ 0.99, concentration range 0.075–120 μg/ml for both analytes). The developed method was successfully applied for the determination of both drugs in plasma to assess the pharmacokinetics in beagle dogs. WCK 4234 + MEM in a 1:1 ratio at 15 + 15 and 30 + 30 mg/kg doses were administered by the intravenous route. The mean plasma concentration and area under the concentration–time curve of WCK 4234 ranged from 38.3 to 77.4 μg/ml and from 47.8 to 77.1 μg h/ml, respectively, and the values for MEM ranged from 52.2 to 115.3 μg/ml and 70.5 to 133.6 μg h/ml respectively. The elimination half-life of WCK 4234 and MEM was around 0.8 h. 相似文献
7.
An efficacious synthesis of N-1–, C-3–substituted indole derivatives and their antimicrobial studies
A novel series of 11 C-3– and N-1–substituted oxoacetamide indole derivatives were synthesized by reacting with various aromatic amines and alkyl halides. These compounds were characterized by using various spectral techniques, ie, 1HNMR, 1HNMR-D2O, 13CNMR, UV, elemental analysis, IR, and mass spectrometery. In vitro, antimicrobial studies of resultant compounds were carried out against two bacterial strains, Pseudomonas aeruginosa and Pseudomonas oryzihabitans using disc plate method. All the tested compounds showed vital efficiency as antimicrobial agents against both the bacterial strains. The results revealed that synthesized indole derivative 2-(1-(3-bromopropyl)-1H-indol-3-yl)-N-(2-nitrophenyl)-2-oxoacetamide displayed the best antimicrobial activity as compared with all other synthesized compounds. 相似文献
8.
Yogesh Patil George Zapsas Yves Gnanou Nikos Hadjichristidis 《Journal of polymer science. Part A, Polymer chemistry》2020,58(1):163-171
This study presents the synthesis and properties of linear PVDF-based amphiphilic triblock terpolymers with PS and PEO, [PVDF-b-PS-b-PEO], by adopting a procedure that involves: (a) iodine-transfer polymerization (ITP) of VDF with 1-iodoperfluorohexane (C6F13I) serving as chain-transfer agent (CTA) to afford C6F13-PVDF-I, (b) ITP of styrene with the C6F13-PVDF-I macromolecular-CTA to obtain C6F13-PVDF-b-PS-I diblock copolymer, (c) end-group exchange from iodo- to azido-group by nucleophilic substitution reaction with NaN3, and (d) copper-catalyzed azide-alkyne cycloaddition (CuAAC) with alkyne-terminated PEO to achieve C6F13-PVDF-b-PS-b-PEO triblock terpolymers. The 1H and 19F NMR spectroscopy confirmed the presence of all blocks, while gel permeation chromatography traces showed the living nature of ITP technique. The self-assembly of these terpolymers was investigated in films (atomic force microscopy and DSC), as well as in aqueous and organic solvents (DLS). The analysis of crystalline phases based on the FTIR spectroscopy indicated the conversion of PVDF α-phase into α + β-phases and β + γ-phases upon the incorporation of PS and PEO blocks, respectively. The synthesized amphiphilic copolymers were evaluated (fluorescence spectroscopy) as carriers of small hydrophobic molecules in water. © 2019 Wiley Periodicals, Inc. J. Polym. Sci. 2020 , 58, 163–171 相似文献
9.
Vivek W. Bhoyare Akash G. Tathe Prof. Vincent Gandon Dr. Nitin T. Patil 《Angewandte Chemie (International ed. in English)》2023,62(46):e202312786
The successful realization of gold-catalyzed chain-walking reactions, facilitated by ligand-enabled Au(I)/Au(III) redox catalysis, has been reported for the first time. This breakthrough has led to the development of gold-catalyzed annulation reaction of alkenes with iodoarenes by leveraging the interplay of chain-walking and π-activation reactivity mode. The reaction mechanism has been elucidated through comprehensive experimental and computational studies. 相似文献
10.
Electroanalytical Studies of Chromone Based Ionophores for the Selective Determination of Arsenite Ion 下载免费PDF全文
Neha Gupta Ashok Kumar Singh Shubhrajyotsna Bhardwaj Divya Singhal 《Electroanalysis》2015,27(5):1166-1175
Two chemosensors 4H‐1‐benzopyran‐3‐carboxaldehyde, 4‐oxo‐, 3‐(2‐phenylhydrazone), [I1] and 4H‐1‐benzopyran‐3‐carboxaldehyde, 4‐oxo‐, 3‐[2‐(2,4‐dinitrophenyl)hydrazone], [I2] with hydrazone‐NH group as binding site have been shown excellent selectivity for arsenite ion. It is confirmed by the UV‐vis titration that I2 is more selective than I1. The performance of the coated graphite electrode (CGE) was found to be better than polymeric membrane electrode (PME) in terms of linear range of 4.89×10?7–1.0×10?1 mol L?1, low detection limit of 8.31×10?8 mol L?1 and short response time. The proposed sensors were also used to determine the arsenite ion in different water samples. 相似文献