And cyclodextrins

ANALYSIS OF MEDICINES BY TEC IN MOBILE PHASES CONTAINING SURFACTANTS AND CYCLODEXTRINES... 

NMR studies of cyclodextrin and cyclodextrin complexes 98CRV1755. Organic reactions mediated by cydodextrins 98CRV2013. 

Covalent and noncovalent combination of porphyrins as well as calix[4]arenes, resorcin[4]arenes including macroheterocyclic fragments, and cyclodextrins by construction of supramolecular artificial receptors 98EJ02689. 

The type of CSPs used have to fulfil the same requirements (resistance, loadabil-ity) as do classical chiral HPLC separations at preparative level [99], although different particle size silica supports are sometimes needed [10]. Again, to date the polysaccharide-derived CSPs have been the most studied in SMB systems, and a large number of racemic compounds have been successfully resolved in this way [95-98, 100-108]. Nevertheless, some applications can also be found with CSPs derived from polyacrylamides [11], Pirkle-type chiral selectors [10] and cyclodextrin derivatives [109]. A system to evaporate the collected fractions and to recover and recycle solvent is sometimes coupled to the SMB. In this context the application of the technique to gas can be advantageous in some cases because this part of the process can be omitted [109]. 

Enantioresolution in capillary electrophoresis (CE) is typically achieved with the help of chiral additives dissolved in the background electrolyte. A number of low as well as high molecular weight compounds such as proteins, antibiotics, crown ethers, and cyclodextrins have already been tested and optimized. Since the mechanism of retention and resolution remains ambiguous, the selection of an additive best suited for the specific separation relies on the one-at-a-time testing of each individual compound, a tedious process at best. Obviously, the use of a mixed library of chiral additives combined with an efficient deconvolution strategy has the potential to accelerate this selection. 

The applications of quantitative structure-reactivity analysis to cyclodextrin com-plexation and cyclodextrin catalysis, mostly from our laboratories, as well as the experimental and theoretical backgrounds of these approaches, are reviewed. These approaches enable us to separate several intermolecular interactions, acting simultaneously, from one another in terms of physicochemical parameters, to evaluate the extent to which each interaction contributes, and to predict thermodynamic stabilities and/or kinetic rate constants experimentally undetermined. Conclusions obtained are mostly consistent with those deduced from experimental measurements. 

The present review is concerned with the applications of the quantitative structure-reactivity analysis to cyclodextrin complexation and cyclodextrin catalysis, mostly from our laboratories, as well as the experimental and theoretical backgrounds of these approaches. 

As shown above, quantitative structure-reactivity analysis is very useful in elucidating the mechanisms of cyclodextrin complexation and cyclodextrin catalysis. This method enables us to separate several intermolecular interactions, acting simultaneously,... 

Solid-surface luminescence analysis involves the measurement of fluorescence and phosphorescence of organic compounds adsorbed on solid materials. Several solid matrices such as filter paper, silica with a polyacrylate binder, sodium acetate, and cyclodextrins have been used in trace organic analysis. Recent monographs have considered the details of solid-surface luminescence analysis (1,2). Solid-surface room-temperature fluorescence (RTF) has been used for several years in organic trace analysis. However, solid-surface room-temperature phosphorescence (RTF) is a relatively new technique, and the experimental conditions for RTF are more critical than for RTF. 

Enzymatic preparation of radiolabeled linear maltodextrins and cyclodextrins 43... 

Nandi I, Bateson M, Bari M, Joshi HN (2003) Synergistic effect of PEG-400 and cyclodextrin to enhance solubility of progesterone. AAPS Pharm Sci Tech 4 E1... 

Menges, R.A., Armstrong, D.W. (1991) Use of a three-phase model with hydroxypropyl-p-cyclodextrin for the direct determination of large octanol-water and cyclodextrin-water partition coefficients. Anal. Chim. Acta 255, 157-162. 

In the following sections the most important features of the organized media that are most frequently used in chemiluminescent reactions (micellar media and cyclodextrins) will be summarized as well as their influence on various chemiluminescent systems, including their corresponding applications in chemical analysis. 

Encapsulation within an enteric coat (resistant to low pH values) protects the product during stomach transit. Microcapsules/spheres utilized have been made from various polymeric substances, including cellulose, polyvinyl alcohol, polymethylacrylates and polystyrene. Delivery systems based upon the use of liposomes and cyclodextrin-protective coats have also been developed. Included in some such systems also are protease inhibitors, such as aprotinin and ovomucoids. Permeation enhancers employed are usually detergent-based substances, which can enhance absorption through the gastrointestinal lining. 

Much of the impetus for the study of reactions in micelles is that they model, to a limited extent, reactions in biological assemblies. Synthetic vesicles and cyclodextrins are other model reaction media and the term Biomimetic Chemistry has been coined to describe this general area of study. Work in this area is reviewed in recent publications (Kunitake and Shinkai, 1980 Fendler, 1982). 

Figure 3.28 Structures of 3,5-dimethylphenylcarbamates of cellooligosaccharides (29), maltooligosaccharides (30), and cyclodextrins (31).

Figure 15.1 Schematic representation of hyperbranched glycocluster having inclusion complex capability, ex. calix[4]arene and / -cyclodextrin...

Explain the basis of host-guest photochemistry and be able to give examples of applications involving micelles, zeolites and cyclodextrins. 

The living character of the ring opening metathesis polymerization described earlier in this review enables a simple preparation of functionalized norbornene-based monoliths. Adding one more in situ derivatization step that involves functional norborn-2-ene and 7-oxanorborn-2-ene monomers that react with the surface-bound initiator, the pores were provided with a number of typical functional groups such as carboxylic acid, tertiary amine, and cyclodextrin [58,59]. 

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