title: Study of the inclusion of the (R)- and (S)-camphor enantiomers in alpha-cyclodextrin by X-ray crystallography and molecular dynamics.
abstract: The inclusion of (R)- and (S)-camphor compounds in alpha-cyclodextrin has been studied by X-ray crystallography. The crystal structures of the complexes reveal that one guest molecule is accommodated inside the cavity formed by a head-to-head cyclodextrin dimer. In the crystal lattice, the dimers form layers which are successively shifted by half a dimer. In both (R)- and (S)-cases, the camphor molecule exhibits disorder and occupies three major sites with orientations that can be described as either 'polar' or 'equatorial'. Molecular dynamics simulations performed for the observed complexes indicate that although the carbonyl oxygen of both (R)- and (S)-camphor switches between different hydrogen bonding partners, it maintains the observed mode of 'polar' or 'equatorial' alignment.
authors.affiliation: Physics Laboratory, Agricultural University of Athens, Iera Odos 75, 118 55 Athens, Greece.
authors.forename: Areti
authors.initials: A
authors.lastname: Kokkinou
authors.forename: Frantzeska
authors.initials: F
authors.lastname: Tsorteki
authors.forename: Michael
authors.initials: M
authors.lastname: Karpusas
authors.forename: Athanasios
authors.initials: A
authors.lastname: Papakyriakou
authors.forename: Kostas
authors.initials: K
authors.lastname: Bethanis
authors.forename: Dimitris
authors.initials: D
authors.lastname: Mentzafos
mesh_terms: D002164:Camphor / Q000737:chemistry*; D018360:Crystallography, X-Ray / Q000379:methods*; D056004:Molecular Dynamics Simulation; D015394:Molecular Structure; D013237:Stereoisomerism; D047391:alpha-Cyclodextrins / Q000737:chemistry*
chemical_list: D047391:alpha-Cyclodextrins; D002164:Camphor; C032613:alpha-cyclodextrin