title: Solid-state supramolecular architecture of carbenoxolone – comparative studies with glycyrrhetinic and glycyrrhizic acids.
abstract: Carbenoxolone (CBXH2), a pharmaceutically relevant derivative of glycyrrhetinic acid, was studied by X-ray crystallography. The crystal structures of its unsolvated form, propionic acid and dimethoxyethane solvates and a solvated cocrystal of the free acid with its monobasic sodium salt CBXH2·CBXHNa·(butan-2-one)2·2H2O reveal that the recurring motif of supramolecular architecture in all crystal forms is a one-dimensional ribbon with closely packed triterpene fragments. It does not result from strong specific interactions but solely from van der Waals interactions. The ribbons are further arranged into diverse layer-type aggregates with a hydrophobic interior (triterpene skeletons) and hydrophilic surfaces covered with carboxylic/carboxylate groups. Solvent molecules included at the interface between the layers influence hydrogen-bonding interactions between the carbenoxolone molecules and organization of the ribbons within the layer. Comparison of crystal structures of carbenoxolone, glycyrrhizic acid and its aglycone-glycyrrhetinic acid have shown the impact of the size and hydrophilic character of the substituent at the triterpene C3 atom on the supramolecular architecture of these three closely related molecules.
authors: Department of Chemical Technology of Drugs, Poznan University of Medical Sciences, Grunwaldzka 6, 60-780 Poznań, Poland.
authors: Ewa
authors: E
authors: Tykarska
authors: Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznań, Poland.
authors: Maria
authors: M
authors: Gdaniec
mesh_terms: D002229:Carbenoxolone / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006034:Glycyrrhetinic Acid / Q000737:chemistry*; D019695:Glycyrrhizic Acid / Q000737:chemistry*; D006860:Hydrogen Bonding; D057927:Hydrophobic and Hydrophilic Interactions; D008958:Models, Molecular; D008968:Molecular Conformation; D015394:Molecular Structure
chemical_list: D019695:Glycyrrhizic Acid; D002229:Carbenoxolone; D006034:Glycyrrhetinic Acid
keywords: solid state structure; supramolecular architecture; triterpene