Functionalized beta-cyclodextrins

Stenzel, M.H. and Davis, T.P. (2002) Star polymer synthesis using trithiocarbonate functional beta-cyclodextrin cotes (Reversible addition-fiagmentation chain-transfer polymerization). Journal of Polymer Scierute Part A-Polymer... 

Numerous examples of modiflcations to the fundamental cyclodextrin structure have appeared in the literature.The aim of much of this work has been to improve the catalytic properties of the cyclodextrins, and thus to develop so-called artificial enzymes. Cyclodextrins themselves have long been known to be capable of catalyzing such reactions as ester hydrolysis by interaction of the guest with the secondary hydroxyl groups around the rim of the cyclodextrin cavity. The replacement, by synthetic methods, of the hydroxyl groups with other functional groups has been shown, however, to improve remarkably the number of reactions capable of catalysis by the cyclodextrins. For example, Breslow and CO workersreported the attachment of the pyridoxamine-pyridoxal coenzyme group to beta cyclodextrin, and thus found a two hundred-fold acceleration of the conversion of indolepyruvic acid into tryptophan. 

Variation of solute retention as a function of the eluent pH. Conditions beta-cyclodextrin-silica pure aqueous eluent pH adjusted by HC1. Column temperature 30 C, eluent flow-rate 1 mL/min. 

Bonomo, RP and V Cucinotta (1991). Conformational features and coordination properties of functionalized cyclodextrins. Formation, stability, and structnre of proton andcopper(ll) complexes of histamine-bearing beta-cyclodextrin in aqueons solntion. Inorganic Chemistry, 30(13), 2708-2713. 

Erankewich RP, Thimmaiah KN, Hinze WL (1991) Evaluation of the relative effectiveness of different water-soluble beta-cyclodextrin media to function as fluorescence enhancement... 

Roche et al. developed a surface plasmon resonance sensor for dextromethorphan based on a molecularly imprinted beta-cyclodextrin polymer with a detection limit of 0.035 pM and a dynamic range of 0.035 pM to 6.00 mM, depending on the instrumental setup [412]. Recently Al-Mustafa etal. have reported liquid selective electrodes for dextromethorphan, based on liquid membranes or graphite electrodes coated with polymers of acrylic acid and 2-vinyl pyridine functional monomers and ethylene... 

Dermody, D.L., et al.. Chemically grafted polymeric filters for chemical sensors hyperbranched poly(acrylic acid) films incorporating beta-cyclodextrin receptors and amine-functionalized filter layers. Langmuir, 1999. 15(3) p. 885-890. Laschewsky, A., et al.. Polyelectrolyte multilayers containing photoreactive groups. Macromol Chem Phys, 1997. 198(10) p. 3239-3253. 

For molecular filtration, Chen et al. [80] fabricated carbonaceous nanoflbrous (CNF) membranes functionalized by beta-cyclodextrins (CNF- -CD membrane). The membrane showed a remarkable capability to function as an ideal molecular Alter through complexation of phenolphthalein molecules with the CD molecules grafted on the CNFs. As a typical dye pollutant, fuchsin acid could also be effectively removed from the solution through such a membrane. Engineering the surface of this CNF membrane may be used for other applications such as chiral separation and drug delivery. 

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