The molecule is a polyanionic polymer obtained by global deprotonation of all the carboxy groups of (1->4)-beta-D-mannuronic acid; major species at pH 7.3. It is a carbohydrate acid anion and a polysaccharide acid oxoanion. It is a conjugate base of a poly[(1->4)-beta-D-mannuronic acid].
(2S,3S,4S,5S,6R)-3,4,5,6-tetrahydroxyoxane-2-carboxylate