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Names | |||
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IUPAC name
D-Xylose
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Other names
(+)-Xylose
Wood sugar |
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Identifiers | |||
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3D model (JSmol)
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ChEMBL | |||
ChemSpider | |||
ECHA InfoCard | 100.117.085 | ||
EC Number | 200-400-7 | ||
PubChem CID
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UNII | |||
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Properties | |||
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)
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+22.5° (CHCl3) | ||
-84.80·10−6 cm3/mol | |||
Hazards | |||
NFPA 704 | |||
Related compounds | |||
Related aldopentoses
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Arabinose Ribose Lyxose |
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Related compounds
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Xylulose | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|||
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 an aldehyde 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 aldehyde 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.