Xylose

D-Xylose

Names
IUPAC name D-Xylose
Other names (+)-Xylose Wood sugar
Identifiers
CAS Number	58-86-6 Y 609-06-3 (L-isomer) Y[ESIS] 41247-05-6 (racemate) Y[ESIS]
3D model (Jmol)	Interactive image
ChEMBL	ChEMBL502135 N
ChemSpider	119104 N
ECHA InfoCard	100.117.085
EC Number	200-400-7
PubChem	135191
UNII	A1TA934AKO Y
InChI InChI=1S/C5H10O5/c6-2-1-10-5(9)4(8)3(2)7/h2-9H,1H2/t2-,3+,4-,5?/m1/s1 N Key: SRBFZHDQGSBBOR-IOVATXLUSA-N N InChI=1/C5H10O5/c6-2-1-10-5(9)4(8)3(2)7/h2-9H,1H2/t2-,3+,4-,5?/m1/s1 Key: SRBFZHDQGSBBOR-IOVATXLUBL
SMILES C1[C@H]([C@@H]([C@H](C(O1)O)O)O)O
Properties
Chemical formula	C5H10O5
Molar mass	150.13 g/mol
Appearance	monoclinic needles or prisms, colourless
Density	1.525 g/cm3 (20 °C)
Melting point	144 to 145 °C (291 to 293 °F; 417 to 418 K)
Chiral rotation ([α]D)	+22.5° (CHCl3)
Magnetic susceptibility (χ)	-84.80·10−6 cm3/mol
Hazards
NFPA 704	1 1 0
Related compounds
Related aldopentoses	Arabinose Ribose Lyxose
Related compounds	Xylulose
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Xylose (cf. Greek: ξύλον, xylon, "wood") is a sugar first isolated from wood, and named for it. Xylose is classified as a monosaccharide of the aldopentose type, which means that it contains five carbon atoms and includes a formyl functional group. It is derived from hemicellulose, one of the main constituents of biomass. Like most sugars, it can adopt several structures depending on conditions. With its free carbonyl group, it is a reducing sugar.

The acyclic form of xylose has chemical formula HOCH₂(CH(OH))₃CHO. The cyclic hemiacetal isomers are more prevalent in solution and are of two types: the pyranoses, which feature six-membered C₅O rings, and the furanoses, which feature five-membered C₄O rings (with a pendant CH₂OH group). Each of these rings subject to further isomerism, depending on the relative orientation of the anomeric hydroxy group.

The dextrorotary form, D-xylose, is the one that usually occurs endogenously in living things. A levorotary form, L-xylose, can be synthesized.

Xylose is the main building block for the hemicellulose xylan, which comprises about 30% of some plants (birch for example), far less in others (spruce and pine have about 9% xylan). Xylose is otherwise pervasive, being found in the embryos of most edible plants. It was first isolated from wood by Finnish scientist, Koch, in 1881, but first became commercially viable, with a price close to sucrose, in 1930.