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排序方式: 共有196条查询结果,搜索用时 15 毫秒
71.
Ankur Kanti Guha 《Journal of organometallic chemistry》2011,696(2):586-593
A systematic density functional investigation has been carried out on the structure, stability and reactivity of heterocyclic carbenes of diverse flexibility, i.e., carbenes with different modes of binding specially normal and remote mode of binding. Ligating properties of these carbenes have been assessed by virtue of their HOMO energies and verified further by inspection of the symmetric CO frequencies of their respective palladium carbonyl complexes. All the remote carbenes were found to have higher σ-donating abilities compared to their normal analogs. N-heterocyclic carbenes 1 and 5 are found to be electrophilic in nature while the remote carbene 3 and P-heterocyclic carbene 6 are found to be nucleophilic. Quantum theory of atoms in molecules (QTAIM) reveals significant covalent character in the Ccarbene-Pd bonds. 相似文献
72.
73.
A new probe (Z)-3-((naphthalen-1-ylmethylene)amino)phenol has been synthesized by condensation reaction between 1-naphthaldehyde and 3-aminophenol for the fluorescent sensing of Ce3+ by “on” mode and dichromate (Cr2O72?) by “off” mode. Metal ions—Ag+, Al3+, As3+, Ba2+, Ca2+, Cd2+, Ce4+, Co2+, Cr3+, Cr6+, Cu2+, Fe2+, Fe3+, Hg2+, K+, La+, Li+, Mg2+, Mn2+, Na+, Ni2+, Pb2+, Zn2+and anions Br?, C2O42?, CH3COO?, Cl?, CO32?, F?, H2PO4?, HCO3?, HF2?, HPO42?, I?, MnO4?, NO3?, OH?, S2?, S2O32?, SCN?, SO42? do not interfere. The limit of detection (LOD) for sensing Ce3+ and Cr2O72? ions are 1.286?×?10–7 M and 6.425?×?10–6 M, respectively.
相似文献74.
Borhade N Pathan AR Halder S Karwa M Dhiman M Pamidiboina V Gund M Deshattiwar JJ Mali SV Deshmukh NJ Senthilkumar SP Gaikwad P Tipparam SG Mudgal J Dutta MC Burhan AU Thakre G Sharma A Deshpande S Desai DC Dubash NP Jain AK Sharma S Nemmani KV Satyam A 《Chemical & pharmaceutical bulletin》2012,60(4):465-481
In continuation of our efforts to discover novel nitric oxide-releasing non-steroidal anti-inflammatory drugs (NO-NSAIDs) as potentially "Safe NSAIDs," we report herein the design, synthesis and evaluation of 21 new NO-NSAIDs of commonly used NSAIDs such as aspirin, diclofenac, naproxen, flurbiprofen, ketoprofen, sulindac, ibuprofen and indomethacin. These prodrugs have NO-releasing disulfide linker attached to a parent NSAID via linkages such as an ester (compounds 9-16), a double ester (compounds 17-24), an imide (compounds 25-30) or an amide (compounds 31-33). Among these NO-NSAIDs, the ester-containing NO-aspirin (9), NO-diclofenac (10), NO-naproxen (11), and the imide-containing NO-aspirin (25), NO-flurbiprofen (27) and NO-ketoprofen (28) have shown promising oral absorption, anti-inflammatory activity and NO-releasing property, and also protected rats from NSAID-induced gastric damage. NO-aspirin compound 25, on further co-evaluation with aspirin at equimolar doses, exhibited comparable dose-dependent pharmacokinetics, inhibition of gastric mucosal prostaglandin E(2) (PGE(2)) synthesis and analgesic properties to those of aspirin, but retained its gastric-sparing properties even after doubling its oral dose. These promising NO-NSAIDs could therefore represent a new class of potentially "Safe NSAIDs" for the treatment of arthritic pain and inflammation. 相似文献
75.
Jarugu Narasimha Moorthy Prof. Dr. Apurba L. Koner Dr. Subhas Samanta Ankur Roy Werner M. Nau Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(17):4289-4300
A variety of differently substituted 6‐ and 7‐arylchromenes such as that depicted undergo photoinduced C? O bond cleavage to yield colored o‐quinonoid intermediates. A combined analysis of μs–ms (laser flash) and real‐time kinetic data show that the o‐quinonoid intermediates decay faster when the C2‐aryl and C6‐/C7‐aryl rings contain electron‐donating and electron‐accepting groups, respectively. Similarly, the decay occurs slowly for the reversed scenario, while intermediate decay rates are observed when both substituents are electron donating.
76.
The effect of catalyst on formation of isomeric ketals from 19-nortestosterone and 19-nor-ethisterone is reported. Regioselectivity has been achieved with metal hydrides as catalyst, reported for the first time, to give 5(10)-ene ketals. 相似文献
77.
We show that there exist series-parallel graphs with boxicity 3. 相似文献
78.
Structural Chemistry - A quantum-chemical study on some super tocopherol derivatives and their heavier chalcogen derivatives has been undertaken to evaluate the antioxidant abilities through... 相似文献
79.
Pritam Mahawar Dr. Mishi Kaushal Wasson Dr. Mahendra Kumar Sharma Dr. Chandan Kumar Jha Dr. Goutam Mukherjee Prof. Dr. Perumal Vivekanandan Prof. Dr. Selvarajan Nagendran 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(48):21561-21565
The biological applications of germylenes remain unrealised owing to their unstable nature. We report the isolation of air-, water-, and culture-medium-stable germylene DPMGeOH ( 3 ; DPM=dipyrromethene ligand) and its potential biological application. Compound 3 exhibits antiproliferative effects comparable to that of cisplatin in human cancer cells. The cytotoxicity of compound 3 on normal epithelial cells is minimal and is similar to that of the currently used anticancer drugs. These findings provide a framework for a plethora of biological studies using germylenes and have important implications for low-valent main-group chemistry. 相似文献
80.
R. S. Kaushal 《International Journal of Theoretical Physics》2001,40(4):835-847
Based on the multidimensional Ermakov theory, a general result that relates the Schrodinger equation and the Milne equation in terms of a space invariant is established. Using this result not only the role of phase in the Wigner function approach to quantum mechanics is demonstrated but also a better explanation for the Aharonov–Bohm effect is sought in terms of a fundamental phase and the matter-field-coupling current. The existence of a similar space invariant is also emphasized for the nonlinear Schrodinger equation. 相似文献