Title: D-Psicose
CAS Registry Number: 551-68-8
Additional Names: D-ribo-2-Ketohexose; D-ribohexulose; D-allulose; D-erythrohexulose; pseudofructose
Molecular Formula: C6H12O6
Molecular Weight: 180.16
Percent Composition: C 40.00%, H 6.71%, O 53.28%
Literature References: Occurrence and identification as a non-fermentable substance in cane molasses: Zerban, Sattler, Ind. Eng. Chem. 34, 1180 (1942). Structure: Ohle, Just, Ber. 68, 601 (1935). Prepn starting with D-ribono-g-lactone: Wolfrom et al., J. Am. Chem. Soc. 67, 1793 (1945); from D-allose: Steiger, Reichstein, Helv. Chim. Acta 19, 184 (1937); from D-glucose: Hough et al., J. Chem. Soc. 1953, 2005.
Properties: Sweet syrupy liquid. [a]D25 +4.7° (c = 4.3 in water; no detectable mutarotation). Soluble in water, methanol, ethanol. Practically insol in acetone.
Optical Rotation: [a]D25 +4.7° (c = 4.3 in water; no detectable mutarotation)
Derivative Type: Phenylosazone
Molecular Formula: C18H22N4O4
Molecular Weight: 358.39
Percent Composition: C 60.32%, H 6.19%, N 15.63%, O 17.86%
Properties: Yellow crystals from water, mp about 162-163° (dec); also reported mp 178°.
Melting point: mp about 162-163° (dec); mp 178°
d-Quercitol Drazoxolon D-Ribose-5-phosphoric Acid D-Ribulose Drimenin

CAS number 23140-52-5 N
PubChem 90008
ChemSpider 81254 YesY
MeSH psicose
ChEBI CHEBI:27605 YesY
Jmol-3D images Image 1
Molecular formula C6H12O6
Molar mass 180.16 g mol−1
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

D-Psicose (D-allulose, D-ribo-2-hexulose, C6H12O6) is an ultralow-energy monosaccharide sugar. It is a C-3 epimer of D-fructose, and is present in small quantities in agricultural products and commercially prepared carbohydrate complexes. It is known as a "rare sugar" because it is rarely found in nature, and even when found, only in small amounts. D-Psicose yields only 0.3% the metabolic energy of the equivalent amount of sucrose.[1] Its name derives from the antibiotic psicofuranine, from which it can be isolated. Research is being conducted into how it can be used in diets to aid in combating hyperglycemia, hyperlipidemia, and obesity. The first mass production method for D-psicose was established when Ken Izumori at Kagawa University in Japan discovered the key enzyme, D-tagatose 3-epimerase, to convert fructose to D-psicose in 1994.[2][3] This method of D-psicose production, called Izumoring named after Izumori, has a high yield but suffers from a very high production cost. In 2012, Food and Drug Administration (FDA) approved D-psicose as a food additive and designated it as generally recognized as safe (GRAS).[4][5]