Apparent molar volume and adiabatic compressibility studies of aqueous solutions of some drug compounds at 25 °C

1989 ◽  
Vol 67 (4) ◽  
pp. 727-735 ◽  
Author(s):  
Mohammad Iqbal ◽  
R. E. Verrall
Keyword(s):  
Aqueous Solutions ◽  
Protein Interactions ◽  
Adiabatic Compressibility ◽  
Structural Features ◽  
Aromatic Rings ◽  
Velocity Measurements ◽  
Drug Molecules ◽  
Aqueous Solvent ◽  
Solute Interactions ◽  
Apparent Molar Adiabatic Compressibilities

Apparent molar adiabatic compressibilities and volumes of aqueous solutions of the following drugs (sodium salicylate, methyl orange, L-tryptophan, phenol, and the hydrochloride salts of propranalol, procaine, pilocarpene, and ephedrine) have been calculated from high precision density and sound velocity measurements at 25 °C. These drugs are considered important in several biochemical phenomena such as anomalous protein binding, anesthesia, or unique structure–activity relationship and this study is part of a comprehensive investigation of drug–protein interactions in biological systems. The data are qualitatively interpreted in terms of solute–solvent and solute–solute interactions. Some plausible modes of drug hydration are discussed with particular reference to the structure of the drug molecules. The adiabatic compressibility shows a strong correlation with the hydrational behaviour of the solute molecule and appears to be sensitive to the structural features of the solute, such as shape, size, branching, and presence of aromatic rings. It is argued that these aspects are important in terms of considering the geometrical fit of the solute into the ordered form of the aqueous solvent surrounding these solutes. Keywords: apparent molar adiabatic compressibilities, apparent molar volumes, hydration of drugs.

scholarly journals Exploration of Diverse Interactions of Some Vitamins in Aqueous Mixtures of Cysteine

2017 ◽  
Vol 58 (2) ◽  
Author(s):  
Mahendra Nath Roy ◽  
Palash Chakraborti
Keyword(s):  
Apparent Molar Volume ◽  
Adiabatic Compressibility ◽  
Viscosity Data ◽  
Aqueous Mixtures ◽  
Lorenz Equation ◽  
Solvent Interactions ◽  
Solute Interactions ◽  
Viscosity B Coefficient ◽  
Diverse Interactions ◽  
Apparent Molar Adiabatic Compressibilities

The apparent molar volume (<em>Φ<sub>V</sub></em>), viscosity B-coefficient, molal refraction (<em>R</em>) and adiabatic compressibility (<em>Φ<sub>K</sub></em>) of Nicotinic Acid, Ascorbic Acid, and Folic Acid have been determined in 0.01, 0.03, 0.05 mol∙dm<sup>-3</sup> aqueous Cysteine solutions at 298.15 K from density (<em>ρ</em>), viscosity (<em>η</em>), refractive index (<em><em>n<sub>D</sub></em></em>) and speed of sound (<em>u</em>) respectively. The limiting apparent molar volumes (<em>Φ<sup>0</sup><sub>V</sub></em>) and experimental slopes (<em>S*<sub>V</sub></em>), derived from the Masson equation, have been interpreted in terms of solute-solvent and solute-solute interactions respectively. The viscosity data were analyzed using the Jones-Dole equation and the derived parameters <em>A</em> and <em>B</em> have also been interpreted in terms of solute-solute and solute-solvent interactions respectively in the solutions. Using the Lorentz-Lorenz equation, molal refractions (<em>R</em>) have been calculated. At infinite dilution, limiting apparent molar adiabatic compressibilities (<em>Φ<sup>0</sup><sub>K</sub></em>) of these vitamins were evaluated and discussed.

Protein Interaction Domains and Post-Translational Modifications: Structural Features and Drug Discovery Applications

2020 ◽  
Vol 27 (37) ◽  
pp. 6306-6355 ◽  
Author(s):  
Marian Vincenzi ◽  
Flavia Anna Mercurio ◽  
Marilisa Leone
Keyword(s):  
Drug Discovery ◽  
Protein Interaction ◽  
Protein Interactions ◽  
Structural Information ◽  
Protein Complexes ◽  
Structural Features ◽  
Protein Protein Interactions ◽  
Modular Architecture ◽  
Post Translational Modifications ◽  
Interaction Domains

Background:: Many pathways regarding healthy cells and/or linked to diseases onset and progression depend on large assemblies including multi-protein complexes. Protein-protein interactions may occur through a vast array of modules known as protein interaction domains (PIDs). Objective:: This review concerns with PIDs recognizing post-translationally modified peptide sequences and intends to provide the scientific community with state of art knowledge on their 3D structures, binding topologies and potential applications in the drug discovery field. Method:: Several databases, such as the Pfam (Protein family), the SMART (Simple Modular Architecture Research Tool) and the PDB (Protein Data Bank), were searched to look for different domain families and gain structural information on protein complexes in which particular PIDs are involved. Recent literature on PIDs and related drug discovery campaigns was retrieved through Pubmed and analyzed. Results and Conclusion:: PIDs are rather versatile as concerning their binding preferences. Many of them recognize specifically only determined amino acid stretches with post-translational modifications, a few others are able to interact with several post-translationally modified sequences or with unmodified ones. Many PIDs can be linked to different diseases including cancer. The tremendous amount of available structural data led to the structure-based design of several molecules targeting protein-protein interactions mediated by PIDs, including peptides, peptidomimetics and small compounds. More studies are needed to fully role out, among different families, PIDs that can be considered reliable therapeutic targets, however, attacking PIDs rather than catalytic domains of a particular protein may represent a route to obtain selective inhibitors.

scholarly journals Ring-Forming Polymerization toward Perfluorocyclobutyl and Ortho-Diynylarene-Derived Materials: From Synthesis to Practical Applications

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1486
Author(s):  
Eugene B. Caldona ◽  
Ernesto I. Borrego ◽  
Ketki E. Shelar ◽  
Karl M. Mukeba ◽  
Dennis W. Smith
Keyword(s):  
Chemical Resistance ◽  
Structural Features ◽  
Review Article ◽  
Aryl Ether ◽  
Aromatic Rings ◽  
Practical Applications ◽  
Repeat Units ◽  
Wide Range ◽  
Synthetic Routes ◽  
The Cost

Many desirable characteristics of polymers arise from the method of polymerization and structural features of their repeat units, which typically are responsible for the polymer’s performance at the cost of processability. While linear alternatives are popular, polymers composed of cyclic repeat units across their backbones have generally been shown to exhibit higher optical transparency, lower water absorption, and higher glass transition temperatures. These specifically include polymers built with either substituted alicyclic structures or aromatic rings, or both. In this review article, we highlight two useful ring-forming polymer groups, perfluorocyclobutyl (PFCB) aryl ether polymers and ortho-diynylarene- (ODA) based thermosets, both demonstrating outstanding thermal stability, chemical resistance, mechanical integrity, and improved processability. Different synthetic routes (with emphasis on ring-forming polymerization) and properties for these polymers are discussed, followed by their relevant applications in a wide range of aspects.

THE WATER-SOLUBLE POLYSACCHARIDES OF DERMATOPHYTES: IV. GALACTOMANNANS I FROM TRICHOPHYTON GRANULOSUM, TRICHOPHYTON INTERDIGITALE, MICROSPORUM QUINCKEANUM, TRICHOPHYTON RUBRUM, AND TRICHOPHYTON SCHÖNLEINII

1965 ◽  
Vol 43 (1) ◽  
pp. 30-39 ◽  
Author(s):  
C. T. Bishop ◽  
M. B. Perry ◽  
F. Blank ◽  
F. P. Cooper
Keyword(s):  
Aqueous Solutions ◽  
Copper Complexes ◽  
Trichophyton Rubrum ◽  
Periodate Oxidation ◽  
Structural Features ◽  
Water Soluble ◽  
Major Constituent ◽  
Branch Points ◽  
Terminal Units ◽  
Hydrolysis Of

A group of polysaccharides, called galactomannans I, were precipitated as their insoluble copper complexes from aqueous solutions of the crude polysaccharides obtained from each of the organisms designated in the title. The five galactomannans I were homogeneous under conditions of electrophoresis and ultracentrifugation and had high positive specific rotations. The major constituent monosaccharide was D-mannose; amounts of D-galactose ranged from nil for the polysaccharide from T. rubrum to 13% for that from T. schönleinii. Methylation and hydrolysis of the five galactomannans I yielded varying amounts of the following: 2,3,5,6-tetra-O-methyl-D-galactose (not present in the products from T. rubrum), 2,3,4,6-tetra-O-methyl-D-mannose, 2,3,4-tri-O-methyl-D-mannose, 2,4,6-tri-O-methyl-D-mannose, 3,4-di-O-methyl-D-mannose, and 3,5-di-O-methyl-D-mannose. Periodate oxidation results agreed with the methylation studies. The gross structural features of each galactomannan I appear to be the same, namely, a basic chain of 1 → 6 linked α-D-mannopyranose units for approximately every 22 of which there is a 1 → 3 linked α-D-mannopyranose residue. Branch points occur along the 1 → 6 linked chain at the C2 positions of the D-mannopyranose units and once in every 45 units at the C2 position of a 1 → 6 linked D-mannofuranose residue. The D-galactose in the polysaccharides is present exclusively as non-reducing terminal furanose units; non-reducing terminal units of D-mannopyranose are also present. The variations in the identities and relative amounts of the non-reducing terminal units were the only apparent differences in the gross structural features within this group of polysaccharides.

scholarly journals Crystal structure of 1,2-bis[(2-tert-butylphenyl)imino]ethane

2015 ◽  
Vol 71 (6) ◽  
pp. o385-o386
Author(s):  
Alexandre C. Silvino ◽  
Juliana M. Torres
Keyword(s):  
Hydrogen Bonds ◽  
Structural Features ◽  
Angular Deviation ◽  
Aromatic Rings ◽  
Acta Cryst ◽  
Compound C ◽  
Angle Deviation ◽  
Steric Factors ◽  
Diimine Ligand ◽  
Intramolecular Hydrogen

The whole molecule of the title compound, C22H28N2, (I), is generated by inversion symmetry. The molecule is rather similar to that of 2,3-bis[(2-tert-butylphenyl)imino]butane, (II), a diimine ligand comprising similar structural features [Ferreiraet al.(2006).Acta Cryst.E62, o4282–o4284]. Both ligands crystallize with the –N=C(R)—C(R)=N– group around an inversion centre, in atransconfiguration. Comparing the two structures, it may be noted that the independent planar groups in both molecules [the central link, –N=C(R)—C(R)=N–, and the terminal aromatic ring] subtend an angle of 69.6 (1)° in (II) and 49.4 (2)° in (I). Ferreira and co-workers proposed that such angle deviation may be ascribed to the presence of two non-classical intramolecular hydrogen bonds and steric factors. In fact, in (I), similar non-classical hydrogen bonds are observed, and the larger angular deviation in (II) may be assigned to the presence of methyl groups in the diimino fragment, which can cause steric hindrance due to the presence of bulkytert-butyl substituents in the aromatic rings. The C=N bond lengths are similar in both compounds and agree with comonly accepted values.

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