title: Conformational interpretation of vescalagin and castalagin physicochemical properties.
abstract: Vescalagin and castalagin are two diastereoisomers. The variability of their principal physicochemical properties, compared with their small structural differences, suggests important conformational variations. This study shows, experimentally, that vescalagin has a greater effect on polarity, oxidizability in solution, and thermodegradability than castalagin. Conformational analysis by molecular mechanics demonstrated that vescalagin was more hydrophilic and was more reactive to electrophilic reagents than castalagin. Experimental results were thus explained and demonstrated the distinct behaviors of vescalagin and castalagin. These results were attributed to the C1 position of the two compounds because vescalin and castalin have comparable characteristics. Experimental data were confirmed and interpreted by molecular mechanics. This work represents one of the first attempts to correlate conformation and the properties of phenolic compounds. This step constitutes a predictive method for the pharmacology or chemistry of new compounds.
authors.affiliation: Tonnellerie Demptos seconded to the CESAMO (Centre d'Etudes Structurales et d'Analyses des Molécules Organiques)--Université Bordeaux I, 351 Cours de la Libération, F-33405 Talence, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Vivas
authors.forename: Michel
authors.initials: M
authors.lastname: Laguerre
authors.forename: Isabelle
authors.initials: I
authors.lastname: Pianet de Boissel
authors.forename: Nathalie
authors.initials: N
authors.lastname: Vivas de Gaulejac
authors.forename: Marie-Françoise
authors.initials: MF
authors.lastname: Nonier
mesh_terms: D001713:Biphenyl Compounds; D002396:Catechols / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D047348:Hydrolyzable Tannins; D008968:Molecular Conformation; D015394:Molecular Structure; D010084:Oxidation-Reduction; D012996:Solutions; D013237:Stereoisomerism; D013329:Structure-Activity Relationship
chemical_list: D001713:Biphenyl Compounds; D002396:Catechols; D047348:Hydrolyzable Tannins; D012996:Solutions; C084709:vescalagin