Results 31 to 40 of about 52,526 (336)
Фармацевтичний журнал, 2019 Among various heterocyclic systems, the derivatives of five-membered heterocycles are of special interest. Most of the above mentioned heterocycles are treatred as so-called privileged structures in modern medicinal chemistry.
І. V. Drapak
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Nature Communications, 2021 Enantioenriched medium-sized silicon-stereogenic heterocycles are in high demand due to the potential use in functional materials. Here, the authors show a rhodium-catalyzed enantioselective synthesis of six- and seven-membered tri-organosubstituted ...
Shuyou Chen +5 more
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Molecular Split-Ring Resonators Based on Metal String Complexes [PDF]
J. Phys. Chem. C 118, 3766 (2014), 2014 Metal string complexes or extended metal atom chains (EMACs) belong to a family of molecules that consist of a linear chain of directly bonded metal atoms embraced helically by four multidentate organic ligands. These four organic ligands are usually made up of repeating pyridyl units, single-nitrogen-substituted heterocyclic annulenes, bridged by ...
arxiv +1 more source
Quantum computation of $π\to π^*$ and $n \to π^*$ excited states of aromatic heterocycles [PDF]
arXiv, 2023 The computation of excited electronic states is an important application for quantum computers. In this work, we simulate the excited state spectra of four aromatic heterocycles on IBM superconducting quantum computers, focusing on active spaces of $\pi \to \pi^*$ and $n \to \pi^*$ excitations.
arxiv
Internal conversion and intersystem crossing pathways in UV excited, isolated uracils and their implications in prebiotic chemistry [PDF]
Phys. Chem. Chem. Phys. 18, 20168 (2016), 2019 The photodynamic properties of molecules determine their ability to survive in harsh radiation environments. As such, the photostability of heterocyclic aromatic compounds to electromagnetic radiation is expected to have been one of the selection pressures influencing the prebiotic chemistry on early Earth.
arxiv +1 more source
Electric deflection of imidazole dimers and trimers in helium nanodroplets: Dipole moments, structure, and fragmentation [PDF]
Journal of Chemical Physics v.153, 081101 (2020), 2020 Deuterated imidazole (IM) molecules, dimers and trimers formed in liquid helium nanodroplets are studied by the electrostatic beam deflection method. Monitoring the deflection profile of (IM)D+ provides a direct way to establish that it is the primary product of the ionization-induced fragmentation both of (IM)2 and (IM)3.
arxiv +1 more source
Direct C–H difluoromethylation of heterocycles via organic photoredox catalysis
Nature Communications, 2020 Heterocycles containing difluoromethyl groups are molecules with potential application in pharmaceutical, agricultural and materials science. Here, the authors show an organophotocatalytic difluoromethylation of heterocycles using O2 as green oxidant and
Wei Zhang +7 more
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CHIMIA, 2023 4-Membered heterocycles are low molecular weight polar scaffolds with intriguing potential for drug discovery. Despite their unquestionable value, methods to access such heterocycles remain scant.
Juan J. Rojas, James A. Bull
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Numerical modeling of the heterocycle intercalated proton-conducting polymers at various mole ratios [PDF]
Solid State Ionics 272, 166-169, 2015, 2014 The kinetic Monte Carlo simulations are employed to study the proton conductivity for anhydrous heterocyclic based polymers. The proton transport is based on a two-step process called the Grotthuss mechanism. In the referring system the proton concentration depends on the relative molar ratio, $x$, of the benzimidazole and the polystyrene sulfonic acid.
arxiv +1 more source
Resolving the structure-energy dilemma at organic-inorganic interfaces: Adsorption of benzene, thiophene, and xenon over coinage metal surfaces [PDF]
, 2021 Semilocal (SL) density functional approximations (DFAs) are widely applied but have limitations due to their inability to incorporate long-range van der Waals (vdW) interaction. Non-local functionals (vdW-DF, VV10, rVV10) or empirical methods (DFT+D, DFT+vdW, DFT+MBD) are used with SL-DFAs to account for such missing interaction. The physisorption of a
arxiv +1 more source