Alpha-Cyclodextrin

α-Cyclodextrin is a hexasaccharide derived from glucose. It is related to the β- (beta) and γ- (gamma) cyclodextrins, which contain seven and eight glucose units, respectively. All cyclodextrins are white, water-soluble solids with minimal toxicity. Cyclodextrins tend to bind other molecules in their quasi-cylindrical interiors. This inclusion (and release) behavior leads to applications in medicine.[1] The compound is of wide interest because it exhibits host–guest properties, forming inclusion compounds.[2]

Alpha-Cyclodextrin
Names
IUPAC name
cyclomaltohexaose
Systematic IUPAC name
cyclohexakis-(1→4)-α-D-glucopyranosyl
Other names
α-cyclodextrin
α-CD
Identifiers
ECHA InfoCard 100.029.995
UNII
Properties
C36H60O30
Molar mass 972.846 g·mol−1
Appearance white solid
Melting point decomposition
14.5 g/100 mL
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Structure
Main article: cyclodextrin § Structure

In α-cyclodextrin, the six glucose subunits are linked end to end via α-1, 4 linkages. The result has the shape of a tapered cylinder, with six primary alcohols on one face and twelve secondary alcohol groups on the other. The exterior surface of cyclodextrins is somewhat hydrophilic whereas the interior core is hydrophobic.

Three representations of α-cyclodextrin.

Applications

α-Cyclodextrin is marketed for a range of medical, healthcare, and food and beverage applications. For drug delivery, this cyclodextrin confers aqueous solubility to hydrophobic drugs and stability to labile drugs.[3]

Crystal structure of a rotaxane with an α-cyclodextrin macrocycle.[4]

Synthesis

Cyclodextrins are natural starch-conversion products. For industrial use, they are manufactured by enzymatic degradation from vegetable raw materials, such as corn or potatoes. First, the starch is liquified either by heat treatment or using α-amylase. Then cyclodextrin glycosyltransferase (CGTase) is added for enzymatic conversion. CGTases produce diverse cyclodextrins. The selectivity of the synthesis can be improved by the addition of specific guests.[1]

gollark: And also it's finite.
gollark: Ignoring length.
gollark: Index funds ARE superior.
gollark: Imagine managed funds.
gollark: I mean, unless you just invest money and get back standard few-percent-a-year increases.

References
  1. József Szejtli (1998). "Introduction and General Overview of Cyclodextrin Chemistry". Chem. Rev. 98 (5): 1743–1754. doi:10.1021/cr970022c. PMID 11848947.
  2. Zhichang Liu, Siva Krishna Mohan Nalluria, J. Fraser Stoddart (2017). "Surveying macrocyclic chemistry: from flexible crown ethers to rigid cyclophanes". Chemical Society Reviews. 46 (9): 2367–2650. doi:10.1039/c7cs00185a. PMID 28462968.CS1 maint: uses authors parameter (link)
  3. Thomas Wimmer (2012). "Cyclodextrins". Ullmann's Encyclopedia of Industrial Chemistry. Wiley-VCH. doi:10.1002/14356007.e08_e02. ISBN 978-3527306732.CS1 maint: uses authors parameter (link)
  4. Stanier, Carol A.; O'Connell, Michael J.; Anderson, Harry L.; Clegg, William (2001). "Synthesis of fluorescent stilbene and tolan rotaxanes by Suzuki coupling". Chemical Communications (5): 493–494. doi:10.1039/b010015n.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.