The molecule is a heparan composed of a backbone of repeating alpha-L-iduronosyl-(1->4)-alpha-D-glucosamine units joined by (1->4)-linkages. It derives from a L-idopyranuronic acid. It is a tautomer of a heparosan L-iduronic acid zwitterion.
(2R,3S,4S,5R,6R)-6-[(2R,3S,4R,5R,6S)-5-amino-4,6-dihydroxy-2-(hydroxymethyl)oxan-3-yl]oxy-3,4,5-trihydroxyoxane-2-carboxylic acid