199 Result(s)
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Article
Open AccessOn substituent effect in 1,n–homodisubstituted polyenes
The all-trans and all-cis polyenes homodisubstituted at the ends were calculated at the B3LYP/6-31G** level. The disubstitution gives rise to three end-types of the conformers: trans-trans, trans-cis, and cis-cis
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Open AccessThermochemistry of monocharged anion substitutions in ionic solids
Modification of materials to achieve specific changes in their physical and chemical properties often involves the substitution of ions. While this process is commonly discussed in structural terms, our recent...
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Open AccessDetermination of dissociation constants of cephalosporin antibiotics by cellmetry method
Acid dissociation constants of three cephalosporin antibiotics (cefapirin, ceftiofur, and cefotaxime) were calculated by a newly developed methodology. Plane-wave DFT calculations were performed to determine t...
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Open AccessAromaticity – a theoretical notion
In 2023, a themed collection on “Emerging frontiers in aromaticity” was published in Chemical Science. The collection included a Perspective Essay entitled “Aromaticity – Quo Vadis”, which presents a wealth of vi...
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Open AccessSeventy-three years riding heterocycles
The Chemical Intelligencer, 1997, 3, 61–64.
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Open AccessThe breakthrough in vaccination: Nobel Prize in Physiology or Medicine 2023
The Nobel Prize of Physiology or Medicine 2023 was awarded jointly to two researchers, Katalin Karikó and Drew Weissman, for their discoveries taking part in the development of effective mRNA vaccines against ...
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Open AccessThermochemistry of monocharged cation substitutions in ionic solids
A rather straightforward synthetic procedure for the production of new materials is the substitution of principal ions in the crystal for one another, and some general principles relating to structure have bee...
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Open AccessCharacterization and properties of a new insensitive explosive co-crystal composed of trinitrotoluene and pyrene
A new energetic co-crystal of trinitrotoluene (TNT) and pyrene (PYRN) with a 1:1 molar ratio was prepared by a slow solvent evaporation technique. Co-crystal physicochemical properties have also been examined ...
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Open AccessTheoretical study of the formation of pyrazole and indazole carbamic acids
A theoretical study of the formation of carbamic acids of pyrazole and indazole has been carried out using DFT computational methods. The effects of the substituents and the solvent (using explicit and implici...
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Open AccessParadoxes and paradigms: elements and compounds: similar names, very different energetics. Part 5, selected examples of exotic species and isotopes (H, He, C, F, U)
In this paper we continue to review the phonetic similarity of trivial names of chemical substances, in the particular, the names of isotopes of selected elements (H, He, C, F, U) of the periodic table. Thermo...
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Open AccessDesign, synthesis, and in silico-in vitro antimalarial evaluation of 1,2,3-triazole-linked dihydropyrimidinone quinoline hybrids
In response to the malaria parasite’s resistance towards quinoline-based antimalarial drugs, we have employed quinoline-containing compounds in combination with dihydropyrimidinone (DHPM) analogues as resistan...
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Open AccessParadoxes and Paradigms: elements and compounds: similar names, very different energetics
In this paper we continue to review the phonetic similarity of trivial names of chemical substances and the names of the elements in the periodic table. Thermochemical properties are explicitly considered. We ...
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Article
Open AccessThe influence of structural isomerism on luminescence properties of [Re(CO)2(dppv)(pbi)] complexes containing cis-1,2-bis(diphenylphosphino)-ethene and 2-(2-pyridyl)benzimidazole ligands
Simple reaction procedure, boiling of an equimolar mixture of [Re(Cl)(CO)3(dppv)] (dppv—cis-1,2-bis(diphenylphosphino)-ethene), 2-(2-pyridyl)benzimidazole (pbi), and TlClO4 in o-dichlorobenzene solution, leads to...
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Open AccessSterically crowded thioamides: deviations from planarity as determined by X-ray structure analyses and quantum chemical calculations
The structures of selected thiobenzamides and some corresponding benzamides with two more or less bulky N-substituents have been studied by single-crystal X-ray diffraction analyses. The planarity of the thioa...
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Open AccessHarnessing data science to improve molecular structure elucidation from tandem mass spectrometry
Compound structural identification for non-targeted screening of organic molecules in complex mixtures is commonly carried out using liquid chromatography coupled to tandem mass spectrometry (UHPLC-HRMS/MS and...
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Open AccessExperimental and computational studies of tautomerism pyridine carbonyl thiosemicarbazide derivatives
Tautomerism is one of the most important phenomena to consider when designing biologically active molecules. In this work, we use NMR spectroscopy, IR, and X-ray analysis as well as quantum-chemical calculatio...
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Article
Open AccessParadoxes and paradigms: elements and compounds – similar names, very different energetics
In this paper we continue to review the phonetic similarity of trivial names of chemical substances and the names of the elements in the periodic table. Thermochemical properties are explicitly considered. We ...
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Article
Open AccessBorane derivatives of five-membered N-heterocyclic rings as frustrated Lewis pairs: activation of CO2
The reaction of seventeen borane derivatives of five-membered N-heterocyclic rings (BNHRs) with CO2 has been studied by means of DFT calculations. Several non-covalent complexes between the BNHRs and CO2 which ev...
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Open AccessFluorescence quenching, DFT, NBO, and TD-DFT calculations on 1, 4-bis [2-benzothiazolyl vinyl] benzene (BVB) and meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) in the presence of silver nanoparticles
Steady-state fluorescence measurements were used to examine the fluorescence quenching of 1, 4-bis [-(2-benzothiazolyl) vinyl benzene (BVB) by sodium salt of meso-tetrakis (4-sulfonatophenyl) porphyrin (TPPS) ...
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Open AccessIdentification of FDA-approved drugs against SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) through computational virtual screening
The SARS-CoV-2 coronavirus is responsible for the COVID-19 outbreak, which overwhelmed millions of people worldwide; hence, there is an urgency to identify appropriate antiviral drugs. This study focuses on sc...
