Cellobiose

Cellobiose is a disaccharide with the formula (C6H7(OH)4O)2O. It is classified as a reducing sugar - any sugar that possesses the ability or function of a reducing agent. The chemical structure of cellulose is derived from the condensation of a pair of β-glucose molecules forming a β(1→4) bond. It can be hydrolyzed to glucose enzymatically or with acid. Cellobiose has eight free alcohol (OH) groups, one acetal linkage, and one hemiacetal linkage, which give rise to strong inter- and intramolecular hydrogen bonds. It is a white solid.

Cellobiose
Names
IUPAC name
4-O-β-D-Glucopyranosyl-β-D-glucopyranose
Systematic IUPAC name
(2Ξ,3R,4R,5S,6R)-6-(Hydroxymethyl)-5-{[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]oxy}oxane-2,3,4-triol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.007.670
KEGG
UNII
  • InChI=1S/C12H22O11/c13-1-3-5(15)6(16)9(19)12(22-3)23-10-4(2-14)21-11(20)8(18)7(10)17/h3-20H,1-2H2/t3-,4-,5-,6+,7-,8-,9-,10-,11?,12+/m1/s1 N
    Key: GUBGYTABKSRVRQ-CUHNMECISA-N N
  • O[C@H]2[C@H](O[C@@H]1O[C@H](CO)[C@@H](O)[C@H](O)[C@H]1O)[C@H](OC(O)[C@@H]2O)CO
Properties
C12H22O11
Molar mass 342.297 g·mol−1
Appearance White, hard powder
Odor Odorless
Density 1.768 g/mL
Melting point 203.5 °C (398.3 °F; 476.6 K) (decomposes)
12 g/100 mL
Solubility Very slightly soluble in alcohol
insoluble in ether, chloroform
log P −5.03
Acidity (pKa) 12.39
Hazards
NFPA 704 (fire diamond)
1
0
0
Safety data sheet (SDS) Sigma-Aldrich
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

It can be obtained by enzymatic or acidic hydrolysis of cellulose and cellulose-rich materials such as cotton, jute, or paper. Cellobiose can be used as an indicator carbohydrate for Crohn's disease and malabsorption syndrome.

Treatment of cellulose with acetic anhydride and sulfuric acid gives cellobiose acetoacetate, of which there is no longer a hydrogen bond donor (though it is still a hydrogen bond acceptor) and possesses aspects of being soluble in nonpolar organic solvents.

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