Induced Circular-dichroism of Conjugated Cyclohexenones Included In Native Or Modified Cyclomaltooligosaccharides

The mode of insertion of conjugated cyclohexenones into native cyclomaltooligosaccharides (cyclodextrins) and heptakis(2,6-diO-methyl)cyclomaltoheptaose, heptakis(2,3,6-tri-O-methyl)cyclomaltoheptaose, and heptakis[6-deoxy-6-(N-methylacetamido)]cyclomaltoheptaose has been inferred from induced c.d. spectra. Depending on the presence of methyl substituents in the cyclohexenone moiety and on the size of the cyclodextrin, the carbonyl group may be forced to penetrate the cavity. The induced c.d. spectra of complexes with heptakis[6-deoxy-6-(N-methylacetamido)]cyclomaltoheptaose show that the carbonyl group of the 6-substituent penetrates into the cavity and, as a result of the cyclohexenone inclusion, it is forced out. © 1986.