How many solvent molecules are required to solvate chiral 1,2-diols with hydrogen bonding solvents? A VCD spectroscopic study

2020 ◽  
Vol 22 (3) ◽  
pp. 1525-1533 ◽  
Author(s):  
Luisa Weirich ◽  
Juliana Magalhães de Oliveira ◽  
Christian Merten
Keyword(s):  
Hydrogen Bonding ◽  
Spectroscopic Study ◽  
Spectroscopic Analysis ◽  
Model Systems ◽  
Solvent Interactions ◽  
Solvent Molecules

A VCD spectroscopic analysis of selected model systems for solute–solvent interactions of chiral diols with hydrogen bonding solvents DMSO and ACN.

scholarly journals Physico-Chemical Studies on Aqueous Solutions of (Amantadine and Oseltamivir) with PEG, Maltodextrin and SLS Binary Complex Formation

2020 ◽  
Vol 10 (1) ◽  
pp. 1950-1958
Keyword(s):  
Hydrogen Bonding ◽  
Complex Formation ◽  
Aqueous Solutions ◽  
Binary Complex ◽  
Total Absorption ◽  
Solvent Interactions ◽  
Ftir Studies ◽  
Physico Chemical ◽  
Chemical Studies ◽  
Solvent Molecules

The molecular interaction between the drug and solvent molecules are discussed. The study aims to increase the solubility, stability, sweetness of drugs by way of complexation. The ultrasonic velocity, density, and viscosity have been measured at 2MHz for the aqueous solutions of (i) Influenza Anti-Viral Drugs + PEG, Maltodextrin, and SLS at different concentrations at a temperature 303K. Some derived parameters from the measured parameters have been computed. These properties are ascribing to molecular interactions through hydrogen bonding. The total absorption can be considered as the sum of contributions from solute-solvent interactions with FTIR studies.

scholarly journals Dispersion-controlled docking preference: multi-spectroscopic study on complexes of dibenzofuran with alcohols and water

2019 ◽  
Vol 21 (29) ◽  
pp. 16032-16046 ◽  
Author(s):  
D. Bernhard ◽  
M. Fatima ◽  
A. Poblotzki ◽  
A. L. Steber ◽  
C. Pérez ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Spectroscopic Study ◽  
Diphenyl Ether ◽  
London Dispersion ◽  
Solvent Molecules

The planarity and rigidity of dibenzofuran inverts the docking preference for increasingly bulky R-OH solvent molecules, compared to the closely related diphenyl ether. Now, London dispersion favors OH⋯π hydrogen bonding.

Effects of Multiple Binding Sites on Studies of Hydrogen Bonding between Nitroxide Radicals and Solvent Molecules

1993 ◽  
Vol 58 (1) ◽  
pp. 47-52 ◽  
Author(s):  
Imad Al-Bala'a ◽  
Richard D. Bates
Keyword(s):  
Hydrogen Bonding ◽  
Magnetic Resonance ◽  
Binding Site ◽  
Binding Sites ◽  
Hyperfine Coupling Constant ◽  
Hydrogen Donor ◽  
Complex Formation Constants ◽  
Multiple Binding Sites ◽  
Multiple Binding ◽  
Solvent Molecules

The role of more than one binding site on a nitroxide free radical in magnetic resonance determinations of the properties of the complex formed with a hydrogen donor is examined. The expression that relates observed hyperfine couplings in EPR spectra to complex formation constants and concentrations of each species in solution becomes much more complex when multiple binding sites are present, but reduces to a simpler form when binding at the two sites occurs independently and the binding at the non-nitroxide site does not produce significant differences in the hyperfine coupling constant in the complexed radical. Effects on studies of hydrogen bonding between multiple binding site nitroxides and hydrogen donor solvent molecules by other magnetic resonance methods are potentially more extreme.

Heats of Solution of Some Sodium and Potassium Salts in Water and in Water-Methanol Mixtures

1992 ◽  
Vol 57 (11) ◽  
pp. 2227-2234 ◽  
Author(s):  
Ján Benko ◽  
Oľga Vollárová
Keyword(s):  
Transfer Functions ◽  
Enthalpies Of Solution ◽  
Potassium Salts ◽  
Solvent Interactions ◽  
Heats Of Solution ◽  
Solvent Molecules ◽  
Sodium And Potassium

The enthalpies of solution ∆Hs0 were determined for NaSCN, KSCN, NaBrO3, KBrO3, NaClO3, KClO3, NaIO4, KMnO4, KNO2 and NaNO2 in water-methanol mixtures. The transfer functions ∆Ht0 of the salts and anions were calculated based on the extrathermodynamic TPTB assumption. The ∆Ht0 values of the anion obtained from the sodium and potassium salts were compared. The differences observed, particularly at higher concentrations of the cosolvent, are discussed with respect to the interactions between the solvent molecules and the solute-solvent interactions.

scholarly journals Hydrogen Bonds: Raman Spectroscopic Study

2021 ◽  
Vol 22 (10) ◽  
pp. 5380
Author(s):  
Boris A. Kolesov
Keyword(s):  
Hydrogen Bonding ◽  
Hydrogen Bonds ◽  
Spectroscopic Study ◽  
Raman Spectra ◽  
Temperature Region ◽  
Vibrational Frequency ◽  
Chemical Compounds ◽  
Raman Spectroscopic ◽  
Raman Spectroscopic Study ◽  
Proton Dynamics

The work outlines general ideas on how the frequency and the intensity of proton vibrations of X–H×××Y hydrogen bonding are formed as the bond evolves from weak to maximally strong bonding. For this purpose, the Raman spectra of different chemical compounds with moderate, strong, and extremely strong hydrogen bonds were obtained in the temperature region of 5 K–300 K. The dependence of the proton vibrational frequency is schematically presented as a function of the rigidity of O-H×××O bonding. The problems of proton dynamics on tautomeric O–H···O bonds are considered. A brief description of the N–H···O and C–H···Y hydrogen bonds is given.

Structure, stability and folding of the α-helix

2001 ◽  
Vol 68 ◽  
pp. 95-110 ◽  
Author(s):  
Andrew J. Doig ◽  
Charles D. Andrew ◽  
Duncan A. E. Cochran ◽  
Eleri Hughes ◽  
Simon Penel ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Hydrophobic Interactions ◽  
Data Bank ◽  
Site Directed Mutagenesis ◽  
Model Systems ◽  
Side Chain ◽  
Structure Stability ◽  
Helical Peptides ◽  
Vast Number ◽  
Α Helix

Pauling first described the α-helix nearly 50 years ago, yet new features of its structure continue to be discovered, using peptide model systems, site-directed mutagenesis, advances in theory, the expansion of the Protein Data Bank and new experimental techniques. Helical peptides in solution form a vast number of structures, including fully helical, fully coiled and partly helical. To interpret peptide results quantitatively it is essential to use a helix/coil model that includes the stabilities of all these conformations. Our models now include terms for helix interiors, capping, side-chain interactions, N-termini and 310-helices. The first three amino acids in a helix (N1, N2 and N3) and the preceding N-cap are unique, as their amide NH groups do not participate in backbone hydrogen bonding. We surveyed their structures in proteins and measured their amino acid preferences. The results are predominantly rationalized by hydrogen bonding to the free NH groups. Stabilizing side-chain-side-chain energies, including hydrophobic interactions, hydrogen bonding and polar/non-polar interactions, were measured accurately in helical peptides. Helices in proteins show a preference for having approximately an integral number of turns so that their N- and C-caps lie on the same side. There are also strong periodic trends in the likelihood of terminating a helix with a Schellman or αL C-cap motif. The kinetics of α-helix folding have been studied with stopped-flow deep ultraviolet circular dichroism using synchrotron radiation as the light source; this gives a far superior signal-to-noise ratio than a conventional instrument. We find that poly(Glu), poly(Lys) and alanine-based peptides fold in milliseconds, with longer peptides showing a transient overshoot in helix content.

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