D-苏糖, D-Threose

D-Threose is a four-carbon monosaccharide or carbohydrate with molecular formula C4H8O4. The prefix "threo" which derives from threose (and "erythro" from a corresponding diastereomer erythrose) offer a useful way to describe general organic structures with adjacent chiral centers, where "the prefixes... designate the relative configuration of the centers". As is depicted in a Fischer projection of D-threose, the adjacent substituents will have a syn orientation in the isomer referred to as "threo", and are anti in the isomer referred to as "erythro".

Title: D-Threose

CAS Registry Number: 95-43-2

CAS Name: (2S,3R)-2,3,4-Trihydroxybutanal

Molecular Formula: C4H8O4

Molecular Weight: 120.10

Percent Composition: C 40.00%, H 6.71%, O 53.29%

Literature References: From calcium D-xylonate by oxidation with H2O2: Ruff, Ber. 34, 1370 (1901). Improved procedure using strontium D-xylonate and ferric acetate catalyst: Hockett, J. Am. Chem. Soc. 57, 2260, 2265 (1935). From tetraacetyl-D-xylononitrile: Maquenne, Compt. Rend. 130, 1403 (1900); Ann. Chim. [7] 24, 404 (1901); Bonner, Roth, J. Am. Chem. Soc. 81, 5454 (1959); from monobenzylidene-D-arabitol: Steiger, Reichstein, Helv. Chim. Acta 19, 1016 (1939); from 1,1-diethylsulfonyl-D-threo-3,4,5-trihydroxypent-1-ene: Hough, Taylor, J. Chem. Soc. 1955, 1212; from D-galactose: Perlin, Brice, Can. J. Chem. 34, 541 (1956). Synthesis of DL-threose: Lake, Glattfeld, J. Am. Chem. Soc. 66, 1091 (1944); Schmid, Grob, Helv. Chim. Acta 32, 77 (1949); Sonogashira, Nakagawa, Bull. Chem. Soc. Jpn. 45, 2616 (1972).

Properties: Syrup. Shows mutarotation. Final [a]D20 -12.3° (20 min, c = 4). Very sol in water; slightly in alcohol. Practically insol in ether, petr ether.

Optical Rotation: [a]D20 -12.3° (20 min, c = 4)

Derivative Type: Phenylosazone

Molecular Formula: C16H18N4O2

Molecular Weight: 298.34

Percent Composition: C 64.41%, H 6.08%, N 18.78%, O 10.73%

Properties: Dec 164-165°. Identical with D-erythrose phenylosazone.

Derivative Type: Triacetate

Molecular Formula: C10H14O7

Molecular Weight: 246.21

Percent Composition: C 48.78%, H 5.73%, O 45.49%

Properties: Prisms from abs ethanol, mp 117-118°. [a]D25 +34.4° (c = 2 in chloroform). Soluble in hot water, chloroform, acetone, ethyl acetate; sparingly sol in abs alcohol, methanol, ether.

Melting point: mp 117-118°

Optical Rotation: [a]D25 +34.4° (c = 2 in chloroform)