Fig. 1.

Fischer projection formula of l-fucose. The six carbons of fucose are numbered. Note that most naturally occurring sugars, such as galactose, are present in the d-configuration, as can be determined by the arrangement of the hydroxyl group bound to the C-5 carbon. Note further that the C-6 carbon of l-fucose lacks a hydroxyl group present at the C-6 position of d-galactose. l-Fucose can also be described as 6-deoxy-l-galactose. This figure is available in black and white in print and in color at Glycobiology online.