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41.
Wu T Nauwelaerts K Van Aerschot A Froeyen M Lescrinier E Herdewijn P 《The Journal of organic chemistry》2006,71(15):5423-5431
A method has been developed for the synthesis of bisheaded nucleosides with thymine and adenine base moieties. We have demonstrated that, when incorporated in oligonucleotides, extrahelical A-T base interactions are possible when the bisheaded nucleosides are positioned in opposite strands of the duplex and are separated from each other by one regular base pair. 相似文献
42.
Guanaes Lais Danciguer Guimarães Matheus Murmel Ducatti Diogo R. B. Duarte Maria Eugênia R. Barreira Sandra M. W. Noseda Miguel D. Gonçalves Alan Guilherme 《Chemistry of Heterocyclic Compounds》2021,57(12):1195-1203
Chemistry of Heterocyclic Compounds - In the present work, we have synthesized new molecular hybrids consisting of porphyrin ring system connected at the meso positions with phenyl groups and/or,... 相似文献
43.
Francisco A. Martins Lucas A. Zeoly Rodrigo A. Cormanich Matheus P. Freitas 《Tetrahedron》2018,74(8):880-883
The preferred conformations of a small polyfunctional molecule containing fluorine, chlorine and hydroxyl groups, the 1-chloro-1,1-difluoro-2-pentanol (CDP), were completely elucidated using 1H, 13C and 19F NMR in three different solvents. While the Cl-C-C-O dihedral angle was asserted using coupling constant data for the diastereotopic fluorines, the Et-C-C-O torsional angle was analyzed by means of 1H NMR spectra with selective irradiation of the diastereotopic hydrogens and fluorines. In addition, unusual couplings of the hydroxyl hydrogen with a diastereotopic hydrogen and fluorines provided information on the O-H orientation. The behavior of 1JC,F when the solvents varied agrees with a weak F???HO intramolecular hydrogen bond. These findings were corroborated, and the governing interactions rationalized with the aid of high level CCSD(T) theoretical calculations. Noteworthy, hyperconjugation involving the electron-acceptor σ*C-Cl orbital drives the conformational equilibrium rather than the fluorine gauche effect. 相似文献
44.
Nicolás Andruskiewitsch João Matheus Jury Giraldi 《Linear and Multilinear Algebra》2018,66(5):961-991
We compute all Nichols algebras of rigid braided vector spaces of dimension 2 that admit a non-trivial quadratic relation. 相似文献
45.
46.
PEG-400 as an efficient reaction medium for the synthesis of 2,4,5-triaryl-1H-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles 总被引:1,自引:0,他引:1
An efficient protocol for the one-pot multicomponent synthesis of various 2,4,5-triaryl- IH-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles using PEG-400 as reaction medium is described. This method has the advantages of good yields, less pollution and simple reaction conditions. 相似文献
47.
48.
Matheus Palhares Viana Bruno A.N. Traven?olo Esther Tanck Luciano da Fontoura Costa 《Physica A》2010,389(8):1771-1778
The properties of complex networks are highly influenced by border effects frequently found as a consequence of the finite nature of real-world networks as well as network sampling. Therefore, it becomes critical to devise effective means for sound estimation of network topological and dynamical properties while avoiding these types of artifacts. In the current work, an algorithm for minimization of border effects is proposed and discussed, and its potential is illustrated with respect to two real-world networks, namely bone canals and air transportation. 相似文献
49.
Matheus Nunes da Rocha Márcia Machado Marinho Alexandre Magno Rodrigues Teixeira Emmanuel Silva Marinho Hélcio Silva dos Santos 《印度化学会志》2022,99(7):100535
Considered one of the chronic diseases in a global state of emergency, diabetes mellitus (DM) may cover an area of 629 million people affected by 2045. The main route of hyperglycemia in the human body is associated with the action of the enzyme aldose reductase on glucose molecules, resulting in the accumulation of sorbitol in blood and tissue cells. Thus, the present study is a high-throughput virtual screening (HTS) of the various molecular datasets available online, as well as an investigation of the pharmacokinetic properties of absorption, distribution, metabolism, excretion, and toxicity (ADMET) and enzyme inhibition aldose reductase from a series of derivatives of rhodanine-3-acetic acid chalcones (D1-8). Four derivatives (D1-4) showed greater oral bioavailability, as they are anions of low relative polarity, showing better viability to interact with the aldose reductase target with a low toxic response to the host. 相似文献
50.
A new free recoverable and reusable mono-alkaloid-type ligand has been synthesized by a simple method.With highly polar groups,the ligand can be recycled and reused eight times to prepare ethyl(2R,3S)-2,3-dihydroxy-3-phenylpropionate with high yield and ee via asymmetric dihydroxylation(AD) reaction. 相似文献