Arabinose

Arabinose is an aldopentose – a monosaccharide containing five carbon atoms, and including an aldehyde (CHO) functional group.

Arabinose

Names
IUPAC name Arabinose
Systematic IUPAC name arabino-Pentose
Other names Pectinose
Identifiers
CAS Number	147-81-9^Y 10323-20-3 (D)^Y 5328-37-0 (L)^Y
3D model (JSmol)	Interactive image Interactive image
ChEBI	CHEBI:46983^Y
ChemSpider	59687^Y
EC Number	205-699-8
PubChem CID	5460291
UNII	509X20752R^Y F0W6ETZ4E5 (D)^Y B40ROO395Z (L)^Y
InChI InChI=1S/C5H10O5/c6-1-3(8)5(10)4(9)2-7/h1,3-5,7-10H,2H2/t3-,4-,5+/m1/s1^Y Key: PYMYPHUHKUWMLA-WDCZJNDASA-N^Y InChI=1/C5H10O5/c6-1-3(8)5(10)4(9)2-7/h1,3-5,7-10H,2H2/t3-,4-,5+/m1/s1 Key: PYMYPHUHKUWMLA-WDCZJNDABW
SMILES O=C[C@@H](O)[C@H](O)[C@H](O)CO C([C@H]([C@H]([C@@H](C=O)O)O)O)O
Properties
Chemical formula	C5H10O5
Molar mass	150.13 g/mol
Appearance	Colorless crystals as prisms or needles
Density	1.585 g/cm^3 (20 °C)
Melting point	164 to 165 °C (327 to 329 °F; 437 to 438 K)
Solubility in water	834 g/1 L (25 °C (77 °F))
Magnetic susceptibility (χ)	−85.70·10^−6 cm^3/mol
Hazards
NFPA 704 (fire diamond)	1 1 0
Related compounds
Related aldopentoses	Ribose Xylose Lyxose
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

Properties

For biosynthetic reasons, most saccharides are almost always more abundant in nature as the "D"-form, or structurally analogous to D-glyceraldehyde. However, L-arabinose is in fact more common than D-arabinose in nature and is found in nature as a component of biopolymers such as hemicellulose and pectin.

The L-arabinose operon, also known as the araBAD operon, has been the subject of much biomolecular research. The operon directs the catabolism of arabinose in E. coli, and it is dynamically activated in the presence of arabinose and the absence of glucose.

A classic method for the organic synthesis of arabinose from glucose is the Wohl degradation.

D-Arabinose
α-D-Arabinofuranose	β-D-Arabinofuranose
α-D-Arabinopyranose	β-D-Arabinopyranose

Etymology

Arabinose gets its name from gum arabic, from which it was first isolated.

Use in foods

Originally commercialized as a sweetener, arabinose is an inhibitor of sucrase, the enzyme that breaks down sucrose into glucose and fructose in the small intestine.

See also

• Arabinosyl nucleosides

Notes

1. The D/L nomenclature does not refer to the molecule's optical rotation properties but to its structural analogy to glyceraldehyde.