4467. d-Glucuronolactone
Nomenclature
Description and references
Found in many plant gums in polymeric combination with other carbohydrates. Important structural constituent of practically all fibrous and connective tissues in the animal organism, cf. d-glucuronic acid. Prepd synthetically from many polysaccharides or suitable glucosides where the hydroxyl at carbon 6 may be oxidized while the other sensitive groups are protected. Prepn: Stacey, J. Chem. Soc. 1939, 1529; Hardegger, Spitz, Helv. Chim. Acta 33, 337 (1950); Marsh, Proc. Biochem. Soc. [Biochem. J.], 50, XI (1951); Mehltretter et al., J. Am. Chem. Soc. 73, 2424 (1951); Phillips, Moody, J. Chem. Soc. 1960, 762. Structure: J. Stanek et al., The Monosaccharides (Academic Press, New York, 1963) p 259. For isoln procedures see the ref under glucuronic acid.
Properties
Crystals from ethanol, mp 176-178°. (Commercial grades, mp 172°.) d430 1.76. [α]D25 +19.8° (c = 5.19). Soluble in water (26.9 g/100 ml of soln); slightly sol in methanol (2.8 g/100 ml). Very slightly sol in abs ethanol (0.7 g/100 ml), in glacial acetic acid (0.3 g/100 ml). The free acid is more sol than the lactone. At room temp an aq soln of glucuronolactone reaches an equilibrium of about 20% lactone and 80% acid within 2 months. At 100° an equilibrium of 60% lactone and 40% free acid is reached within 2 hrs. Initial pH of 10% aq soln 3.5, after 1 week the pH is about 2.5.Therapeutic Category
Detoxicant.