title: Diastereoisomer-selective inclusion complexation of Cinchona alkaloids with a modified beta-cyclodextrin: fluorescent behavior enhanced by chiral-tether binding. Short communication.
abstract: The molecular 1:1 complexation of cinchona alkaloids by mono(6-deoxy-6-{[(R)-1-(hydroxymethyl)propyl]amino})-beta-cyclodextrin (1) in aqueous solution has been investigated by 2D-NMR, fluorescence titration, and fluorescence-lifetime experiments. Generally, with 1 as the host, in contrast to beta-cyclodextrin proper, strong binding of quinine (2; Ka = 84,200 M(-1)) and quinidine (3; Ka = 27,300 M(-1)) at pH 6.8 was observed, as monitored by an increase in fluorescence intensity, with a fair degree of diastereoisomer discrimination (ca. 3:1). To rationalize these results, two possible cooperative complexation modes, including specific H-bonding interactions to the chiral tether of the cyclodextrin portion, are proposed.
authors.affiliation: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, PR China. yuliu@public.tpt.tj.cn
authors.forename: Yu
authors.initials: Y
authors.lastname: Liu
authors.forename: Ying-Wei
authors.initials: YW
authors.lastname: Yang
authors.forename: Heng-Yi
authors.initials: HY
authors.lastname: Zhang
authors.forename: Bo-Wen
authors.initials: BW
authors.lastname: Hu
authors.forename: Fei
authors.initials: F
authors.lastname: Ding
authors.forename: Chun-Ju
authors.initials: CJ
authors.lastname: Li
mesh_terms: D001665:Binding Sites / Q000502:physiology; D002930:Cinchona Alkaloids / Q000737:chemistry* / Q000378:metabolism; D008958:Models, Molecular; D013050:Spectrometry, Fluorescence / Q000379:methods; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D002930:Cinchona Alkaloids; D047392:beta-Cyclodextrins; C031215:betadex