Hydroxyethyl-starchにおけるHydroxyethyl基結合位置の研究

抄録

Hydroxyethyl-starch, whose DS is 0.51 by Lortz method and intrinsic viscosity is 0.22 dl/g, was hydrolyzed with sulfuric acid to monosugar units. These monosugars were separated by paper chromatography and then by thin-layer chromatography to five fractions, which were identified as D-glucose, 6-O-hydroxyethyl-D-glucose (6-HEG), 3-O-hydroxyethyl-D-glucose (3-HEG), 2-O-hydroxyethyl-D-glucose (2-HEG), and cis-1, 2-O-ethylene-D-glucofuranose (1, 2-EGF). Molecular concentration ratio of the fractions determined by spectrophotometry using anthrone was 0.479 : 0.103 : 0.029 : 0.299 : 0.090 for D-glucose : 6-HEG : 3-HEG : 2-HEG : 1, 2-EGF. DS calculated from the molecular concentration of D-glucose was about 0.52, showing coincidence with DS by Lortz method. Since 1, 2-EGF, a dehydro isomer of 2-HEG, also showed the substitution at C-2 position of glucose unit in hydroxyethyl-starch, distribution ratio of hydroxyethyl groups on the C-2, C-6, and C-3 was calculated to be about 75%, 20%, and 5%, respectively.