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7-Hydroxycoumarin exhibits antioxidative, lipoxygenase inhibitive and anti-tumourigenic effects. Density and viscosity measurements have been carried out for the solutions of 7-hydroxycoumarin in mixture solvents of water and ethanol or 1-propanol at T = (293.15, 298.15, 303.15, 308.15 and 313.15) K. The measured data have been used to evaluate apparent molar volumes ( Vϕ), limiting apparent molar volumes ( $$ V_{\phi }^{0} $$ V ϕ 0 ), viscosity B-coefficients of the Jones–Dole equation and variation of B with temperature (d B/d T). The values of $$ V_{\phi }^{0} $$ V ϕ 0 and B-coefficients are positive and pass through their corresponding maxima at about 18 mol·kg −1 ethanol molality and 20 mol·kg −1 1-propanol molality, respectively. Besides, the values of $$ V_{\phi }^{0} $$ V ϕ 0 and B-coefficients decrease with increasing temperature. Molar refractive indices ( RD) of the ternary solutions at the temperature of 298.15 K have also been determined from measured refractive indices ( nD). There is an obvious increase of RD with increasing molality of the solvent. These parameters have been interpreted in terms of solute–solvent interactions and structure making/breaking ability of components in the aqueous solution. The temperature and concentration dependences of the weak interactions in the solution systems have also been discussed. [ABSTRACT FROM AUTHOR]

Densitiesand viscosities of the pseudo binary system 7-hydroxy-4-methylcoumarin+ (ethanol or 1-propanol) + water at temperatures of (293.15, 298.15,303.15, 308.15, and 313.15) K and refractive indices of this systemat T= 298.15 K have been measured as a functionof the molality of 7-hydroxy-4-methylcoumarin. The density data havebeen used to compute the apparent molar volume and limiting partialmolar volume. The viscosity B-coefficients and variationof Bwith temperature have been calculated from theviscosity data according to the Jones–Dole equation. Molarrefractions of the investigated system have been obtained from therefractive index data. These parameters and their variation tendencieshave been expounded in terms of the interactions between solutes andsolvents. The results have shown that 7-hydroxy-4-methylcoumarin playsa structure-making role in the given solution. [ABSTRACT FROM AUTHOR]

Abstract: The solubilities of quercetin, a slightly water-soluble flavonoid drug, as a function of different concentrations of cyclodextrins (hydroxypropyl-β-cyclodextrin, HP-βCD; sulfobutyl ether-β-cyclodextrin, SBE-βCD; and methylated-β-cyclodextrin, M-βCD) in Tris–HCl buffer solutions of pH7.4 at different temperatures (from 298.15K to 313.15K) were investigated. The results showed a linear increase in the solubility of quercetin with the increasing molality of CDs at the same temperature. The solubility of quercetin determined with the three CDs followed the rank order SBE-βCD>HP-βCD>M-βCD. Solubilities of quercetin increase in the three CD solutions with an increase in temperature. The experimental solubility data were well-correlated as a function of molalities of CDs and temperature. [Copyright &y& Elsevier]