Day: November 21, 2022

Kassimi, N. El-Bakali published the artcilePolarizabilities of Aromatic Five-Membered Rings: Azoles, Safety of 4H-1,2,4-Triazole, the publication is Journal of Physical Chemistry (1995), 99(34), 12790-6, database is CAplus.

Ab initio, electron correlated calculations of dipole moments and static dipole polarizabilities are reported for ten heteroaromatic five-membered rings: pyrrole, pyrazole, imidazole, all four triazoles, both tetrazole tautomers, and the hypothetical pentazole. They are expected to be accurate to within 5%. Structural isomerism affects the dipole moments strongly, but the dipole polarizabilities are rather insensitive to it. Uncoupled Hartree-Fock calculations indicate that only about half the polarizability comes from the π electrons. Simple empirical formulas correlate the calculated polarizabilities quite well. Aromaticity scales based on polarizabilities are discussed.

Journal of Physical Chemistry published new progress about 63598-71-0. 63598-71-0 belongs to triazoles, auxiliary class Triazole, name is 4H-1,2,4-Triazole, and the molecular formula is C2H3N3, Safety of 4H-1,2,4-Triazole.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Oziminski, Wojciech P. published the artcileDFT studies on tautomerism of C5-substituted 1,2,3-triazoles, Computed Properties of 84406-63-3, the publication is Journal of Molecular Structure (2003), 697-704, database is CAplus.

DFT (B3PW91/6-311++G**), ab initio (HF/6-311++G**), and single point CCSD(T)/6-311++G**//B3PW91/6-311++G** calculations were performed to investigate the stability and tautomerism of the C5-substituted 1,2,3-triazoles. Three different tautomers are possible for the substituted 1,2,3-triazoles: N1-H, N2-H, and N3-H. For all the substituents applied, the most stable is the N2-H tautomer. Out of the two less stable tautomers, N1-H and N3-H, the -F, -CFO, -CH₃, -CHO, -Cl, -CN, -CONH₂, -NH₂, -NO₂, and -OH substituents stabilize the N3-H tautomer, whereas only the -BH₂, -BF₂, and -COOH substituents stabilize the N1-H form. The relative stability of the C5-substituted 1,2,3-triazoles tautomerism is strongly influenced by the possibility for intramol. interactions (both attractive and repulsive) between substituent and protons located either at N1 or N3 atom. For all the mols. studied, the Gibbs free energy at 0 and 298 K was estimated, too.

Journal of Molecular Structure published new progress about 84406-63-3. 84406-63-3 belongs to triazoles, auxiliary class Triazole,Nitro Compound, name is 4-Nitro-2H-1,2,3-triazole, and the molecular formula is C2H2N4O2, Computed Properties of 84406-63-3.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Oziminski, Wojciech P. published the artcileDFT studies on tautomerism of C5-substituted 1,2,3-triazoles, Name: 5-Nitro-1H-1,2,3-triazole, the publication is Journal of Molecular Structure (2003), 697-704, database is CAplus.

DFT (B3PW91/6-311++G**), ab initio (HF/6-311++G**), and single point CCSD(T)/6-311++G**//B3PW91/6-311++G** calculations were performed to investigate the stability and tautomerism of the C5-substituted 1,2,3-triazoles. Three different tautomers are possible for the substituted 1,2,3-triazoles: N1-H, N2-H, and N3-H. For all the substituents applied, the most stable is the N2-H tautomer. Out of the two less stable tautomers, N1-H and N3-H, the -F, -CFO, -CH₃, -CHO, -Cl, -CN, -CONH₂, -NH₂, -NO₂, and -OH substituents stabilize the N3-H tautomer, whereas only the -BH₂, -BF₂, and -COOH substituents stabilize the N1-H form. The relative stability of the C5-substituted 1,2,3-triazoles tautomerism is strongly influenced by the possibility for intramol. interactions (both attractive and repulsive) between substituent and protons located either at N1 or N3 atom. For all the mols. studied, the Gibbs free energy at 0 and 298 K was estimated, too.

Journal of Molecular Structure published new progress about 14544-45-7. 14544-45-7 belongs to triazoles, auxiliary class Triazoles, name is 5-Nitro-1H-1,2,3-triazole, and the molecular formula is C2H2N4O2, Name: 5-Nitro-1H-1,2,3-triazole.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Krylova, Valentina A. published the artcileStructural and Photophysical Studies of Phosphorescent Three-Coordinate Copper(I) Complexes Supported by an N-Heterocyclic Carbene Ligand, Category: triazoles, the publication is Organometallics (2012), 31(22), 7983-7993, database is CAplus.

A series of four neutral luminescent three-coordinate Cu(I) complexes (IPr)Cu(N-N), where IPr is a monodentate N-heterocyclic carbene (NHC) ligand (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and N-N denotes monoanionic pyridylazolate ligands, have been synthesized and characterized. A monomeric, three-coordinate geometry, best described as distorted trigonal planar, has been established by single-crystal x-ray analyses for three of the derivatives In contrast to the previously reported (IPr)Cu(N-N) complexes, the compounds described here display a perpendicular orientation between the chelating N-N ligands and the imidazolylidene ring of the carbene ligand. The geometrical preferences revealed by x-ray crystallog. correlate well with the NMR data. The conformational behavior of the complexes, investigated by variable-temperature ¹H NMR spectroscopy, indicate free rotation about the C_NHC-Cu bond in solution The complexes display broad, featureless luminescence at both room temperature and 77 K, with emission maxima that vary between 555 and 632 nm depending on sample conditions. Luminescence quantum efficiencies of the complexes in solution (Φ ≤ 17%) increase markedly in the solid state (Φ ≤ 62%). On the basis of time-dependent d. functional theory (TD-DFT) calculations and the exptl. data, luminescence is assigned to phosphorescence from a metal-to-ligand charge-transfer (MLCT) triplet state admixed with ligand-centered (LC) character.

Organometallics published new progress about 219508-27-7. 219508-27-7 belongs to triazoles, auxiliary class Trifluoromethylated Building Blocks, name is 2-[5-(Trifluoromethyl)-1H-1,2,4-triazol-3-yl]pyridine, and the molecular formula is C8H5F3N4, Category: triazoles.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Li, Liangjing published the artcileSynthesis and evaluation of novel azoles as potent antifungal agents, Recommanded Product: 1-((2-(2,4-Difluorophenyl)oxiran-2-yl)methyl)-1H-1,2,4-triazole methanesulfonate, the publication is Bioorganic & Medicinal Chemistry Letters (2014), 24(1), 192-194, database is CAplus and MEDLINE.

Using a rational approach to the design of antifungal agents, a series of azole agents with 1,3,4-oxadiazole side chains I were designed and synthesized. The results of preliminary in vitro antifungal tests with eight human pathogenic compounds showed that all of the title compounds exhibited excellent activities against all of the tested fungi except Aspergillus fumigatus. Compounds I (R = 2-Cl or R = 3-Cl) were the most effective, with a min. inhibitory concentration of 0.0039 μg/mL, followed by voriconazole, which has a MIC of 0.0625 μg/mL. The 1,3,4-oxadiazole side chain is not the major contributor but plays a role in eliciting the observed antifungal activity.

Bioorganic & Medicinal Chemistry Letters published new progress about 86386-77-8. 86386-77-8 belongs to triazoles, auxiliary class Epoxides,Triazole,Fluoride,Salt,Sulfonic acid,Benzene, name is 1-((2-(2,4-Difluorophenyl)oxiran-2-yl)methyl)-1H-1,2,4-triazole methanesulfonate, and the molecular formula is C12H13F2N3O4S, Recommanded Product: 1-((2-(2,4-Difluorophenyl)oxiran-2-yl)methyl)-1H-1,2,4-triazole methanesulfonate.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

McOwen, Dennis W. published the artcileAnion Coordination Interactions in Solvates with the Lithium Salts LiDCTA and LiTDI, Related Products of triazoles, the publication is Journal of Physical Chemistry C (2014), 118(15), 7781-7787, database is CAplus.

Lithium 4,5-dicyano-1,2,3-triazolate (LiDCTA, 15) and lithium 2-trifluoromethyl-4,5-dicyanoimidazole (LiTDI, 16) are two salts proposed for lithium battery electrolyte applications, but little is known about the manner in which the DCTA^– and TDI^– anions coordinate Li⁺ cations. To explore this in depth, crystal structures are reported here for two solvates with LiDCTA-(G2)₁:LiDCTA (3) and (G1)₁:LiDCTA (2) with diglyme and monoglyme, resp.; and seven solvates with LiTDI-(G1)₂:LiTDI (5), (G2)₂:LiTDI (6), (G3)₁:LiTDI (7), (THF)₁:LiTDI (9), (EC)₁:LiTDI (10), (PC)₁:LiTDI (11), and (DMC)_1/2:LiTDI (12) with monoglyme, diglyme, triglyme, THF, ethylene carbonate, propylene carbonate, and di-Me carbonate, resp. These latter solvate structures are compared with the previously reported acetonitrile (AN)₂:LiTDI structure. The solvates indicate that the LiTDI salt is much less associated than the LiDCTA salt and that the ions in LiTDI, when aggregated in solvates, have a very similar TDI^–···Li⁺ cation mode of coordination through both the anion ring and cyano nitrogen atoms. Such coordination facilitates the formation of polymeric ion aggregates, instead of dimers. Insight into such ion speciation is instrumental for understanding the electrolyte properties of aprotic solvent mixtures with these salts.

Journal of Physical Chemistry C published new progress about 53817-16-6. 53817-16-6 belongs to triazoles, auxiliary class Triazoles, name is 1H-1,2,3-Triazole-4,5-dicarbonitrile, and the molecular formula is C4HN5, Related Products of triazoles.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Catalan, Javier published the artcileThe azoles: a theoretical study, Computed Properties of 63598-71-0, the publication is Chemica Scripta (1984), 24(2), 84-91, database is CAplus.

Ab initio calculations were reported for 35 azoles (neutral mols. and protonated azolium salts) based on INDO optimized geometries. Calculated dipole moments agreed with measured values. Protonation sites (most basic N atoms) were determined from calculated protonation energies and N lone pair changes. Linear relations between exptl. aqueous basicity and calculated protonation energies for N-methylazoles and between exptl. aqueous acidity for N-unsubstituted azoles and the charge of the NH H atom, were observed Tautomerism of the triazoles and tetrazoles were discussed.

Chemica Scripta published new progress about 63598-71-0. 63598-71-0 belongs to triazoles, auxiliary class Triazole, name is 4H-1,2,4-Triazole, and the molecular formula is C2H3N3, Computed Properties of 63598-71-0.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Mo, O. published the artcileProtonation energies and tautomerism of azoles. Basis set effects, HPLC of Formula: 63598-71-0, the publication is Journal of Physical Chemistry (1986), 90(22), 5597-604, database is CAplus.

The structure, protonation energies, tautomerism, and vertical ionization potentials of several azoles are examined by ab initio calculations using different basis sets ranging from minimal to split valence plus polarization. Minimal basis tends to overestimate all N-N and C-N lengths. Though, in general, 3-21G geometries are close to 6-31G structures, the former basis does not always correct the deficiencies of minimal basis. In general, 6-31G structures agree with the exptl. ones. Azoles with more than one basic N atom protonate preferentially on imidazolic rather than on pyrazolic type N atoms. Minimal basis significantly overestimates absolute protonation energies, but the deviations observed for relative protonation energies are not always of the same sign. Both 3-21G and 6-31G absolute protonation energies are almost equal and much smaller than those obtained at the minimal basis level. The inclusion of polarization functions in the basis (6-31G^*//6-31G calculations) leads to a further decrease in absolute protonation energies which depends on the degree of anisotropy of the charge distribution of the center which undergoes protonation. The relative stabilities of the tautomers change with the basis set. These changes are particularly important for triazolium and tetrazolium cations, as well as for pyrazole and imidazole. For 1,2,4-triazoles, tetrazoles, and 1H-pentazole Koopman’s theorem predicts the wrong ionization potential.

Journal of Physical Chemistry published new progress about 63598-71-0. 63598-71-0 belongs to triazoles, auxiliary class Triazole, name is 4H-1,2,4-Triazole, and the molecular formula is C2H3N3, HPLC of Formula: 63598-71-0.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Del Valle, J. C. published the artcileA theoretical study of the acidity of nitrogen heterocycles, Formula: C2H3N3, the publication is Journal of Molecular Structure: THEOCHEM (1992), 481-91, database is CAplus.

INDO and AM1 calculations of C-H and N-H deprotonation (acidity) of 20 nitrogen heterocycles were performed. Acidity is explained by taking into account lone pair repulsion, aza, and annelation effects. The AM1 method has to be corrected by adding 9 kcal mol^-1 for each adjacent lone pair-lone pair interaction.

Journal of Molecular Structure: THEOCHEM published new progress about 63598-71-0. 63598-71-0 belongs to triazoles, auxiliary class Triazole, name is 4H-1,2,4-Triazole, and the molecular formula is C2H3N3, Formula: C2H3N3.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics

Gyoneva, Stefka published the artcileSystemic inflammation regulates microglial responses to tissue damage in vivo., Synthetic Route of 377727-87-2, the publication is Glia (2014), 62(8), 1345-60, database is MEDLINE.

Microglia, the resident immune cells of the central nervous system, exist in either a “resting” state associated with physiological tissue surveillance or an “activated” state in neuroinflammation. We recently showed that ATP is the primary chemoattractor to tissue damage in vivo and elicits opposite effects on the motility of activated microglia in vitro through activation of adenosine A2A receptors. However, whether systemic inflammation affects microglial responses to tissue damage in vivo remains largely unknown. Using in vivo two-photon imaging of mice, we show that injection of lipopolysaccharide (LPS) at levels that can produce both clear neuroinflammation and some features of sepsis significantly reduced the rate of microglial response to laser-induced ablation injury in vivo. Under proinflammatory conditions, microglial processes initially retracted from the ablation site, but subsequently moved toward and engulfed the damaged area. Analyzing the process dynamics in 3D cultures of primary microglia indicated that only A2A , but not A1 or A3 receptors, mediate process retraction in LPS-activated microglia. The A2A receptor antagonists caffeine and preladenant reduced adenosine-mediated process retraction in activated microglia in vitro. Finally, administration of preladenant before induction of laser ablation in vivo accelerated the microglial response to injury following systemic inflammation. The regulation of rapid microglial responses to sites of injury by A2A receptors could have implications for their ability to respond to the neuronal death occurring under conditions of neuroinflammation in neurodegenerative disorders.

Glia published new progress about 377727-87-2. 377727-87-2 belongs to triazoles, auxiliary class GPCR/G Protein,Adenosine Receptor, name is 2-(Furan-2-yl)-7-(2-(4-(4-(2-methoxyethoxy)phenyl)piperazin-1-yl)ethyl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine, and the molecular formula is C25H29N9O3, Synthetic Route of 377727-87-2.

Referemce:
https://en.wikipedia.org/wiki/1,2,3-Triazole,
Triazoles – an overview | ScienceDirect Topics