MODIFIED CYCLODEXTRINS AS CHIRAL SELECTORS - MOLECULAR MODELING INVESTIGATIONS ON THE ENANTIOSELECTIVE BINDING-PROPERTIES OF HYL-6-O-TERT-BUTYLDIMETHYLSILYL)-BETA-CYCLODEXTRIN

Molecular modelling methods have been used to investigate the enantios elective binding properties of chiral dihydrofuranones on yl-6-O-tert. -butyldimethylsilyl)-beta-cyclodextrin in capillary gas chromatography . A conformational analysis of the modified beta-cyclodextrin was perf ormed using annealed molecular dynamics. With the program GRID the mol ecular interaction potential for each of the received energetically re asonable structures of the beta-cyclodextrin and the dihydrofuranones was evaluated using different probe groups. The results of these compu tations have been used as starting points for constructing geometrical ly reasonable host-guest complexes between the beta-cyclodextrin and t he dihydrofuranones. The subsequently performed molecular dynamics sim ulations yielded different complex states reflecting the conformationa l flexibility of the diastereomeric complexes. Considering the evaluat ed interaction energy between the beta-cyclodextrin and the dihydrofur anones as a measure of complex stability the results are in close agre ement with the experimentally determined elution sequences. The method ology for the construction of the interaction model used in this study is capable of simulating the experimental data. We believe that it ma y serve as a basis for predictions of hitherto unknown elution sequenc es at modified cyclodextrins. (C) 1998 Elsevier Science B.V.