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Hydrogen bonding

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Investigation of the hydrogen bond donating ability of 1,8-naphthalenediol by NMR spectroscopy and its use as a hydrogen bonding catalyst

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as hydrogen bonding catalysts.

Synthesis, characterization, and luminescence of zinc(II) and cadmium(II) coordination complexes: [Zn(phen)2(CH3COO)](ClO4), [Zn(bpy)2(ClO4)](ClO4), and [Cd(phen)2(NO3)2]

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Three-dimensional frameworks of complexes 1–3 are produced by hydrogen bonding, and π − π and C-H.

Methyl-substituted 2-aminothiazole–based cobalt(II) and silver(I) complexes: Synthesis, X-ray structures, and biological activities

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Compound 1 is a much more active antioxidant (67% and 65% against DPPH and ABTS, respectively) than compound 2 (62% and 59%, respectively), which can probably be attributed to the difference in the extent of hydrogen bonding existing in both the compounds. In compound 1, a chloro ligand is involved in intramolecular hydrogen bonding with nitrogen of the amino group on both sides and the other chloro ligand is involved in intermolecular hydrogen bonding (Figure 2).

A new cocrystal explosive trinitrotoluene (TNT): 1-amino-4-bromonaphthalene with reduced sensitivity

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The TNT:ABN cocrystal possesses hydrogen bonds, halogen bonds, and π − π stacking interactions and are indicated in Figures 6a–6c. Single-crystal X-ray refinement factor for TNT:ABN.. Hydrogen bonding. TNT-ABN N H O . TNT-ABN C Br O . Hydrogen bonding (amino–nitro) (a), halogen bonding (Br–nitro) (b), π − π stacking (c).. Hirshfeld surfaces analysis. The color intensity shows the relative strength of the interactions.

Hóa đại cương - Phần 2

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Bonding in Ethylene Bonding in Ethylene. Bonding in Acetylene Bonding in Acetylene. Dipole-Dipole Forces Dipole-Dipole Forces. Hydrogen Bonds Hydrogen Bonds. masses yet the boiling point for water is approximately 200oC higher than that for methane. The higher boiling point is due to:. hydrogen bonding in water polarity of water molecules. both of the above none of the above

Binding of flavanone with β -CD/ctDNA: a spectroscopic investigation

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Thus the benzopyranone part of FL might be involved in the binding with DNA by means of hydrogen bonding and electrostatic interaction, respectively.. of FL (in mol dm -3. a) Absorption spectra of FL in varying concentrations of ctDNA b) Plot of 1/[DNA] vs. Molecular modeling poses of FL with a) Hydrogen bonding of DNA b) Electrostatic interaction of DNA..

Preparation and property assessment of eco-friendly composite based on polyvinyl alcohol and lignin extracted from biomass

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Characterization of hydrogen bonding interactions between PVA and lignin in the composites. Chemical structures of PVA and lignin were illustrated by FTIR spectra (Figure 1).

Study of Langmuir Monolayers of Arachidic Acid on Saline Solutions Using Sum-frequency Generation Vibrational Spectroscopy

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The presence of fluoride (F. on the other hand, shows an enhancement of the hydrogen bonding of water at the interface. R., Vibrational Spectroscopy of Water at the Vapor/Water Interface, Physical Review Letters . Tobias, Ions at the Air/Water Interface, Journal Physical Chemistry B . Richmond, Probing the Molecular Structure and Bonding of the Surface of Aqueous Salt Solutions, Journal Physical Chemistry B

Handbook of Nanotechnology P2

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In analogy to the polypeptide chains of proteins, the amino acid residues of this artificial oligopeptide can sustain hydrogen bonding interactions.. The walls of the resulting nanotubes are maintained in position by the cooperative action of at least eight primary hydrogen bonding contacts per macrocycle. Electroactive and photoactive components can be integrated chemically into functional molecular machines [2.9].

Molecular docking analysis and molecular dynamics simulation study of ameltolide analogous as a sodium channel blocker

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This molecular docking shows in compounds I, VII, and IX that the oxygen of NO 2 forms hydrogen bonding with Ser84 of domain II-S6 (Figure 4). The oxygen of imide in compounds VIII and XV and the OH of compound XIII form a hydrogen bonding interaction with the OH of Thr87 (Figures 5 and 6). In compounds IV and VI, the NH of amide and the NH of the piperidine ring form a hydrogen bonding interaction with the Asn84 of domain III and Glu7B of domain II, respectively (Figure 7)..

Schiff base of isoniazid and ketoprofen: synthesis, X-ray crystallographic, spectroscopic, antioxidant, and computational studies

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The optimized geometry of the Schiff base dimer by applying M06-2X/6-31G(d,p) method showing hydrogen bond and atom labels.. NBO analysis showed donor–acceptor interactions in the hydrogen bonding of the dimer Schiff base structure. This is because of the delocalization of the lone pair orbitals (nN) of N43 LP and N90 LP to the antibonding orbitals ( σ.

C2 -Symmetric chiral diamine ligands for enantiomeric recognition of amino acid esters and mandelic acid by proton NMR titration method

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Probably, while amino acids preferred hydrogen bonding interaction in complexation, mandelic acid preferred π − πand hydrogen bonding interaction. Thus, the greater enantioselectivity of mandelic acid may be explained by forming a rigid structured complex between L-mandelic acid by appropriate π − πstacking interaction of the. 2 aromatic rings of the host and 1 of the guest and the hydrogen bonding interaction between amine groups of the host and –OH groups of the guest.

Integration of bimetallic organic frameworks and magnetic biochar for azole fungicides removal

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This demonstrated that hydrogen bonding between C = O of MBC@Fe/Mg-MIL-88B and N of azole fungi- cides (Hu et al., 2021). The reasons might account for the phenomena were that hydrogen bonding between -NH of MBC@Fe/Mg-MIL-88B and N of azole fungicides, and π - π stacking based on C = N of MBC@Fe/Mg-MIL-88B and aromatic rings of azole fungicides (Chen et al., 2020. Zhao et al., 2021)..

Novel bis(aminoalcohol)oxalamide organogelators and their diglycolylamide analogs: Evaluation of gelation efficiency in various organic fluids

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FTIR was employed to see the effect of hydrogen bonding in the formation of gel network.

Fluorescence quenching study of moxifloxacin interaction with calf thymus DNA

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. –118.4 KJ mol − 1 and ∆S = –299.4 J mol − 1 K − 1 ) were calculated at different temperatures, and they indicate that the main forces between MOX and ct-DNA are hydrogen bonding and Van der Waals force.

Introduction to Modern Liquid Chromatography, Third Edition part 28

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(c) hydrogen bonding of an acceptor (basic) solute group by a donor (acidic) group within the stationary phase (usually a silanol –SiOH). (d) hydrogen bonding of a donor (acidic) solute group by an acceptor (basic) group within the stationary phase (represented here by a group ‘‘X. within the stationary phase. Figure 5.20 Solute-column interactions that determine column selectivity (figures omit the connecting silane group [–Si(CH 3 ) 2.

Introduction to Modern Liquid Chromatography, Third Edition part 75

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Inclusion complexation is often driven by polar interactions, notably for carboxylic acid-containing solutes: triple hydrogen-bonding of the carboxylic terminus (sup- ported by other hydrogen bonding interactions), as well as π – π and hydrophobic interactions (RP mode only).

DFT study of tautomerism in aklavinone

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The stabilities of the presently considered tautomers seem to be affected by intramolecular hydrogen bonding. Figure 2 shows the geometry optimized structures (some bond lengths are displayed too) of aklavinone and its tautomers presently considered. As seen in the figure, in structures 2 and 3 hydrogen bonding is clearly seen between the –OH group(s) and the keto or -OH group(s) next to it.

Excellent organic dye adsorption capacity and recyclability of hydrothermally synthesized a-Fe2O3 nanoplates and nanorices

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The adsorption studies showed a good selectivity and high adsorption capacity (~93%) of the a -Fe 2 O 3 nanoplates towards congo red (C.R.) dye, due to the formation of hydrogen bonding between amine group ( e NH 2 ) of C.R. and surface carboxylate group ( e COOH), and adsorbed e OH groups of a -Fe 2 O 3 nanoplates.

Chapter 043. Jaundice (Part 1)

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This is due to tight internal hydrogen bonding between the water-soluble moieties of bilirubin, proprionic acid carboxyl groups of one dipyrrolic half of the molecule. with the imino and lactam groups of the opposite half. The remaining 10–20% of the urobilinogens are passively absorbed, enter the portal venous blood, and are reexcreted by the liver.