Investigation of the spatial orientation of the hydroxy group and the intramolecular hydrogen bond in stereoisomeric 2,9-dimethyl- and 1,2,9-trimethyldecahydro-4-quinolols and their 4-ethynyl-substituted derivatives by IR spectroscopy

1980 ◽  
Vol 16 (6) ◽  
pp. 617-621
Author(s):  
N. I. Garbuz ◽  
L. I. Ukhova ◽  
N. F. Uskova ◽  
V. Z. Kurbako ◽  
A. A. Akhrem
Keyword(s):  
Hydrogen Bond ◽  
Ir Spectroscopy ◽  
Hydroxy Group ◽  
Intramolecular Hydrogen Bond ◽  
Spatial Orientation ◽  
Intramolecular Hydrogen

scholarly journals Synthesis and isomerism of hydrazones of 2-(5-thioxo-4,5-dihydro-1,3,4-thiadiazol-2-ylthio)acetohydrazide

2007 ◽  
Vol 5 (4) ◽  
pp. 996-1006 ◽  
Author(s):  
Zenonas Kuodis ◽  
Albertas Rutavičius ◽  
Algirdas Matijoška ◽  
Olegas Eicher-Lorka
Keyword(s):  
Hydrogen Bond ◽  
Nitrogen Atom ◽  
Hydroxy Group ◽  
Intramolecular Hydrogen Bond ◽  
1H Nmr ◽  
Nmr Spectra ◽  
1H Nmr Spectra ◽  
Imino Group ◽  
Anti Conformer ◽  
Intramolecular Hydrogen

AbstractNew hydrazones of 2-(5-thioxo-4,5-dihydro-1,3,4-thiadiazol-2-ylthio)acetohydrazide have been obtained and the percentages of anti/syn - conformers were determined. Based on the analyses of 1H NMR spectra, it was concluded that for hydrazones obtained from the 2- hydroxybenzaldehydes and 2’-hydroxycetophenones the ratio between the anti-and syn-conformers depends on the strength of intramolecular hydrogen bond (IMHB) between the nitrogen atom of the imino group and the proton of the 2-hydroxy group. It was shown that increase in IMHB strength results in stabilization of the anti-conformer in solution.

Synthesis and conformation of some 6-aminomethyluracil amides

1990 ◽  
Vol 55 (11) ◽  
pp. 2731-2737 ◽  
Author(s):  
Ivan Stibor ◽  
David Šaman ◽  
Pavel Fiedler
Keyword(s):  
Hydrogen Bond ◽  
Ir Spectroscopy ◽  
Intramolecular Hydrogen Bond ◽  
Amide Carbonyl ◽  
Intramolecular Hydrogen

Three model amides (I-III) derived from 6-(N-alkylaminomethyl)-uracil and arylcarboxylic acids were synthesized and their conformation in solution studied. The 7-membered intramolecular hydrogen bond between amide carbonyl and H-N1 of uracil nucleus was proved to exist in solution of all three compounds using NMR and IR spectroscopy.

scholarly journals 3,5-Diphenyl-1-(quinolin-2-yl)-4,5-dihydro-1H-pyrazol-5-ol

2012 ◽  
Vol 68 (8) ◽  
pp. o2310-o2311
Author(s):  
Muhd. Hidayat bin Najib ◽  
Ai Ling Tan ◽  
David J. Young ◽  
Seik Weng Ng ◽  
Edward R. T. Tiekink
Keyword(s):  
Hydrogen Bond ◽  
Dihedral Angle ◽  
Hydroxy Group ◽  
Intramolecular Hydrogen Bond ◽  
Title Compound ◽  
Phenyl Ring ◽  
Pyrazole Ring ◽  
Quinoline Ring ◽  
Compound C ◽  
Intramolecular Hydrogen

In the title compound, C24H19N3O, the pyrazole ring is close to being planar (r.m.s. deviation of the five fitted atoms = 0.062 Å), and each of theN-bound quinoline ring [dihedral angle = 9.90 (7)°] and theC-bound phenyl ring in the 3-position is close to being coplanar [dihedral angle = 8.87 (9)°]. However, the phenyl ring in the 5-position forms a dihedral angle of 72.31 (9)°. The hydroxy group forms an intramolecular hydrogen bond to the quinoline N atom. In the crystal, molecules are connected into supramolecular layers two molecules thick in thebcplane by C—H...O and C—H...π interactions.

scholarly journals 1-Hydroxy-2-methoxy-6-methyl-9,10-anthraquinone fromRennellia ellipticaKorth.

2009 ◽  
Vol 65 (6) ◽  
pp. o1435-o1435 ◽  
Author(s):  
Nor Hadiani Ismail ◽  
Che Puteh Osman ◽  
Rohaya Ahmad ◽  
Khalijah Awang ◽  
Seik Weng Ng
Keyword(s):  
Hydrogen Bond ◽  
Solid State ◽  
Hydroxy Group ◽  
Intramolecular Hydrogen Bond ◽  
Title Compound ◽  
Independent Molecule ◽  
Asymmetric Unit ◽  
Compound C ◽  
Planar Molecules ◽  
Intramolecular Hydrogen

The title compound, C16H12O4, exists as planar molecules in the solid state (r.m.s. deviation of 0.02 Å in one molecule and 0.07 Å in the second independent molecule comprising the asymmetric unit). In each molecule, the 1-hydroxy group forms an intramolecular hydrogen bond to the adjacent carbonyl O atom.

Effect of the intramolecular hydrogen bond in the active metabolite analogs of leflunomide for blocking the Plasmodium falciparum dihydroorotate dehydrogenase enzyme: QTAIM, NBO, and docking study

2020 ◽  
Vol 16 ◽  
Author(s):  
Reihaneh Heidarian ◽  
Mansoureh Zahedi-Tabrizi
Keyword(s):  
Hydrogen Bond ◽  
Plasmodium Falciparum ◽  
Molecular Orbital ◽  
Intramolecular Hydrogen Bond ◽  
Active Metabolite ◽  
Chemical Hardness ◽  
Dihydroorotate Dehydrogenase ◽  
Molecular Orbital Analysis ◽  
Intramolecular Hydrogen ◽  
Orbital Analysis

: Leflunomide (LFM) and its active metabolite, teriflunomide (TFM), have drawn a lot of attention for their anticancer activities, treatment of rheumatoid arthritis and malaria due to their capability to inhibit dihydroorotate dehydrogenase (DHODH) and Plasmodium falciparum dihydroorotate dehydrogenase (PfDHODH) enzyme. In this investigation, the strength of intramolecular hydrogen bond (IHB) in five analogs of TFM (ATFM) has been analyzed employing density functional theory (DFT) using B3LYP/6-311++G (d, p) level and molecular orbital analysis in the gas phase and water solution. A detailed electronic structure study has been performed using the quantum theory of atoms in molecules (QTAIM) and the hydrogen bond energies (EHB) of stable conformer obtained in the range of 76-97 kJ/mol, as a medium hydrogen bond. The effect of substitution on the IHB nature has been studied by natural bond orbital analysis (NBO). 1H NMR calculations show an upward trend in the proton chemical shift of the enolic proton in the chelated ring (14.5 to 15.7ppm) by increasing the IHB strength. All the calculations confirmed the strongest IHB in 5-F-ATFM and the weakest IHB in 2-F-ATFM. Molecular orbital analysis, including the HOMO-LUMO gap and chemical hardness, was performed to compare the reactivity of inhibitors. Finally, molecular docking analysis was carried out to identify the potency of inhibition of these compounds against PfDHODH enzyme.

Sign in / Sign up

Export Citation Format

Share Document