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A glucan is a polysaccharide derived from D-glucose,[1] linked by glycosidic bonds. Many beta-glucans are medically important, they represent a drug target for antifungal medications of the echinocandin class.


The following are glucans: (The α- and β- and numbers clarify the type of O-glycosidic bond.)




Properties of glucans include resistance to oral acids/enzyme and water insolubility. Glucans extracted from grains tend to be both soluble and insoluble.


Glucans are polysaccharides derived from glucose monomers; the monomers are linked by glycosidic bonds. Four types of glucose-based polysaccharides are possible: 1,6- (starch), 1,4- (cellulose), 1,3- (laminarin), and 1,2-bonded glucans.

Chemical structure of levoglucosan.png

The first representatives of main chain unhydrolysable linear polymers made up of levoglucosan units were synthesized in 1985 by anionic polymerization of 2,3-epoxy derivatives of levoglucosan (1,6;2,3-dianhydro-4-O-alkyl-β-D-mannopyranoses).[2]


A wide range of unique monomers with different radical R can be synthesized.[3] There were synthesized polymers with R= -CH3,[2] -CH2CHCH2,[4] and -CH2C6H5.[5] Investigation of the polymerization kinetics of those derivatives, molecular weight and molecular-weight distribution showed that the polymerization has the features of a living polymerization system; the process takes place without termination and transfer of the polymer chain with a degree of polymerization equal to the mole ratio of the monomer to the initiator.[6][7] Accordingly, the upper value molecular weight polymer determines only degree of purification system what determine the presence in the system uncontrollable amount of terminators of polymer chains.

Poly(2-3)-D-glucose was synthesized proceeds by transformation of benzyl (R= -CH2C6H5) functionalized polymer.[5]


Polymerization of 3,4-epoxy levoglucosan (1,6;3,4-dianhydro-2-O-alkyl-β-D-galactopyranose) [8] results in formation 3,4-bounded levoglucosan polymer.


The presence of 1,6-anhydro structure in every unit of polymer chains allows researchers to apply all spectra of well developed methods of carbohydrate chemistry with formation of highly intriguing biological application polymers; the polymers are the only known regular polyethers built up of carbohydrate units in main polymer chain.[9][10]

See also[edit]


  1. ^ Glucans at the US National Library of Medicine Medical Subject Headings (MeSH)
  2. ^ a b Berman, E.L., Gorkovenko A.A., Zubov, V.P., and Ponomarenko, V.A.,"Regio and Stereospecific Synthesis of Polyglucose with Novel Type BondSoviet J.Bioorg. Chem. 11 (1985), 1125-1129
  3. ^ Carlson, LJ (November 1965). "Preparation of 2- and 4-Substituted D-Glucose Derivatives from 1,6-Anhydro-β-D- glucopyranose". The Journal of Organic Chemistry. 30 (11): 3953–3955. doi:10.1021/jo01022a517.
  4. ^ Gorkovenko, A.A., Berman, E.L., and Ponomarenko, V.A. Polymerization of 1, 6;2,3 dianhydro 4 O allyl β D manno¬pyranose" Vysocomol. Soed., Ser. B, 1987, 29, 134 137
  5. ^ a b Gorkovenko, A.A., Berman, E.L., and Ponomarenko, V.A. "A New Polymer of Glucose. Poly(2 3) D glucose" Soviet J. Bioorg. Chem., 1987, 13, 218 222
  6. ^ Berman, E.L., Gorkovenko, A.A., Rogozhkina, E.D., Izumnikov, A.A., and Ponomarenko, V.A. “Kinetics and Mechanism of Epoxy Ring-Opening Polymerization of 1,6;2,3-Dianhydro-4-O-alkyl-b-D-mannopyranoses” Polymer Sci. USSR, 1988, 413-418
  7. ^ Berman E.L. Gorkovenko, A.A., Rogozhkina, E.D., Izyumnikov, A.L., and Ponomarenko, V.A. "Synthesis of Chiral Derivatives of Poly(Ethylene Oxide)" Bull. Acad. Sci. USSR, Div. Chem. Sci., 1988, 705 707
  8. ^ Gorkovenko A. A., Berman, E.L., and Ponomarenko, V.A., Poly(3 4) 2 O methyl 1,6 anhydro b D glucopyranose. The First Example of (3 4) linked Polymer Carbohydrates" Soviet J. Bioorg. Chem. 12 (1986), 514-520
  9. ^ Berman E.L., Gorkovenko, A.A., and Ponomarenko, V.A. "Structure and Polymerizability of 1,6;2,3 and 1,6;3,4¬ Dianhydrohexapyranoses" Polymer Sci. USSR, 1988, 30, 497¬-502
  10. ^ Berman, E.L., “New Glucose Polymers” in “Levoglucosenone and Levoglucosanes: Symposium: 204th National meeting”, Zbigniew J. Witczak (editor), American Chemical Society. Division of Carbohydrate Chemistry, 189-214. Publisher: A T L Press, Scientific Publishers ISBN 978-1-882360-13-0 ISBN 1882360133