Reaktionen der glucuronsäure : 7. Mitt. Oxidationen an d-glucofuranosidurono-6,3-lactonen

Methyl α-D- (1) and methyl β-D-glucofuranosidurono-6,3-lactone (5) were oxidized at C-2 or C-5, 1,2-O-isopropylidene-α-D- (10) and 1,2-O-cyclohexylidene-α-D-glucofuranurono-6,3-lactone (11) at C-5 by various methods to the corresponding D-arabino- or D-xylo-hexulofuranosiduronolactones. In contrast to the starting materials 5, 10, and 11, the 5-uloses 15, 17, and 18 do not exhibit reducing power in alkaline Cu²⁺ solutions. Methyl 5-O-benzyl-α-D- and methyl 5-O-benzyl-β-D-arabino-2-hexulofuranosidurono-6,3-lactone reduce Benedict solution at room temperature.