The molecule is a beta-D-glucan consisting of (1->4)-beta-D-glucan in which the residue at the non-reducing end has undergone formal dehyderogenation resulting on conversion of the hydroxy group at position 4 to the corresponding ketone.
(2R,4R,5R,6R)-4,5-dihydroxy-2-(hydroxymethyl)-6-[(2R,3S,4R,5R,6R)-4,5,6-trihydroxy-2-(hydroxymethyl)oxan-3-yl]oxyoxan-3-one