Physical-chemical Properties of Substituted Amides in Aqueous Solution and Evaluation of Their Potential Use as Solubilizing Agents

Treatment of thermodynamic nonideality in equilibrium studies on associating solutes

“…Use of a property such as the osmotic pressure of an associating macromolecular system to study the association equilibrium requires allowance to be made for thermodynamic nonideality. We may express this in terms of the activity coefficient of each species i by In 7¡ = oturni + ,, , + higher terms (1) where mi, the concentration of species i, is conveniently expressed on a molal basis; an and ay are constant coefficients expressing interactions of species i with itself and other species ;'. Except for the necessary identities m¡2 + aijmymj (4) Although it would be possible, in principle, to obtain values of Xj, an, aij, and ajj by applying eq 3 and 4 to a sufficiently large series of measurements, this procedure would be impracticable; first, because it would demand an impossibly high standard of accuracy in the measurements; secondly, because eq 3 and 4 cannot be solved explicitly.…”

“…Figure1. Geometric model used in the derivation of eq 18 as the covolume for two ellipsoids of revolution.…”

Lyotropic liquid crystal behaviour of azelate and succinate monoester surfactants based on fragrance alcohols

“…A patent [13] mentions the use of sodium monotocopheryl azelate for cosmetic lotions, though not particularly for its surfactant properties. Only a handful of surfactants synthesised from azelaic acid have been reported in the literature [12][13][14][15][16][17][18][19]. Those are mostly used in detergents or cosmetic emulsions and none of them are commercially available.…”

The dielectric constant and dipole moment of N,N,N',N'-tetramethylpimelamide at 25.degree.C

“…The solubility of a solute in a solvent is the result of several factors, one of which is the dielectric characteristic of the solvent. /V.yv./V'AZ-Tetramethylpimelamide (TMPA), an organic liquid miscible with water in all proportions at 25 °C, exhibits good potential as a solubilizer for poorly soluble drugs (5). The solvent properties of this amide can be attributed to the strong dipole of the amide group and to the good electron donating properties of the carbonyl group.…”

“…Experimental Section /, /, /' /-Tetramethylpimelamide was prepared according to a previous procedure (5). The synthesis involved the conversion of pimelic acid (Eastman Kodak Co., Rochester, N.Y.) to pimeloyl chloride by treatment with excess thionyl chloride (Fisher Scientific Co., Fairlawn, N.J.).…”