Małgorzata Koźbiał

Chiral discrimination of amino acids and their potassium or sodium salts by optically active crown ether derived from d-mannose

Chiral naphtho-18-crown-6 incorporating α-methyl d-mannopyranoside unit exhibits a pronounced chiral discrimination of amino acids in their zwitterionic form, or as potassium and sodium salts in transport across the bulk liquid membrane containing the carrier, as well as in the extraction experiments from the water phase to chloroform phase containing the receptor. The dl selectivity strongly depends on the species used (neutral amino acids, or their salts), and in some cases the reversed selectivity within the same amino acid enantiomers has been observed, indicating the influence of the cation involved.

Aqueous solubilities, infinite dilution activity coefficients and octanol-water partition coefficients of tricyclic analogs of acyclovir

AbstractSolubilities of tricyclic analogs of acyclovir have been determined in water at 25, 35, and 45°C and in octanol, water-saturated octanol, and octanol-saturated water at 25°C. Octanol-water partition coefficients were determined at 25°C. Melting temperatures and molar enthalpies of fusion were measured. Activity coefficients in water, octanol, and in aqueous octanol solutions were determined and are discussed. The effect of hydrophilic and hydrophobic substituents in the tricyclic analogs on their thermodynamic properties are discussed. The standard Gibbs energy of transfer between the saturated phases were found to correlate with known values of the melting point of the solvents and the solubilities of the solute. For a number of the compounds examined, correlations between the minimum inhibitory concentration against the herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), varicella-zoster virus (VZV), thymidine kinase-deficient (TK−) strains of VZV and

One-step alkali metal ion promoted macrobicyclization. Synthesis of (m-xylyl2.2)-cryptand

\Delta G_{{\text{W}} \to {\text{0}}}^0 ;\Delta G_{{\text{tr}}}^0

Complexation of flutamide by native and modified cyclodextrins

were established. Detailed conclusions have been derived concerning the relationships between the structure and the thermodynamic parameters of the compounds examined.

Mixed-ligand terbium terephthalates: Synthesis, photophysical and thermal properties and use for luminescent terbium terephthalate thin film deposition

Calixarenes are very versatile macrocyclic molecular receptors comprising phenolic units. Their easy availability, complexing features and possibility for a variety of chemical modifications makes them particularly attractive to serve as target molecules for various studies in supramolecular chemistry. Three monograph books on calixarene chemistry appeared to date [1–3].

Structural diversity in native cyclodextrins/folic acid complexes – from [2]-rotaxane to exclusion compound

A single step, alkali metal ion-assisted macrobicyclization reaction between α,α′-diamino-m-xylene and eitherbis(2-iodoethoxy) ethane or bis(2-p-toluenesulphonyloxyethoxy)ethane affords (m-xylyl 2.2)-cryptand in good yield. Clear evidence for a template effect is found with the sodium cation. This method offers an alternative route to 4,13-diaza-18-crown-6.

Enhancement of aqueous solubility of tricyclic acyclovir derivatives by their complexation with hydroxypropyl-β-cyclodextrin

The complexation of pteroic acid and pterine, subunits of folic acid, with native cyclodextrins (α‒, β‒, and γ‒CDs) was studied in solution (UV-vis), and in the solid state (thermal analysis, IR and Raman). UV-vis titrations at pH = 7.4 provided data regarding stoichiometry of the formed complexes as well as their associations constants. Stability of the complexes increases in the series: γ‒CD < β‒CD << α‒CD for pterine, and γ‒CD < α‒CD << β‒CD for pteroic acid. The mode of complexation was further exploited by molecular modeling studies (docking studies, PM6) showing additionally changes in conformation of pteroic acid upon complexation. Comparison of the association constants of the complexes of pterine and pteroic acid with native cyclodextrins with data obtained for analogous complexes with folic acid shows that all folic acid complexes are less stable than those formed from its subunits.