Bicyclic Piperazine Mimetics of the Peptide β-Turn Assembled via the Castagnoli-Cushman Reaction.

5-Oxopiperazine-2-carboxamides and respective carboxylic acids (obtained by the Castagnoli-Cushman reaction of protected iminodiacetic anhydride) were converted into cis- and trans-configured bicyclic piperazines containing two stereogenic centers. The latter are not only well-established mimetics of peptide β-turn but also attractive, high-F cores for drug design in general. The methodology was applied to the preparation of ring-expanded version of bicyclic piperazines not described in the literature.

Microspherical Particles of Solid Dispersion of Polyvinylpyrrolidone K29-32 for Inhalation Administration.

Inhalation administration is a promising alternative to the invasive drug delivery methods. The particle size required for ideal drug aerosol preparation is between 1 and 3 m. The application of microspherical particles of solid dispersions enhances bioavailability of poorly soluble drugs due to the solubilization.

A study of the formation of magnetically active solid dispersions of phenacetin using atomic and magnetic force microscopy.

A lot of pharmaceutical substances have a poor solubility that limits their absorption and distribution to the targeted sites to elicit the desired action without causing untoward effects on healthy cells or tissues. For such drugs, new modes of delivery have to be developed for efficient and effective delivery of the drug to the target site. Formation of magnetically active solid dispersion of such drugs could be a useful approach to addressing this problem because they combine targeted delivery and good solubility.

Thermodynamics of dissolution and infrared-spectroscopy of solid dispersions of phenacetin.

In this work enthalpies of dissolution in water of polyethylene glycols (PEGs) having an average molecular weight of 1000 and 1400, Pluronic-F127, phenacetin as well as the composites prepared from them were measured using solution calorimetry at 298.15 K. Intermolecular interaction energies of polymer-phenacetin were calculated on the basis of an additive scheme.

[The effect of the acetylation phenotype on the course severity and outcome of acute viral hepatitis B].

Acetylation phenotype was studied in 70 inpatients with acute viral hepatitis B. Of them, 51 had fast and 19 slow acetylation. Fast-type acetylation was associated with mild-severe form of hepatitis B, while slow-type acetylation--with recurrences and aggravations, severe form of hepatitis.