Fucoidan

(→2)-α-L-fucan(1→), (→3)-α-L-fucan(1→) sulfated at C(4) [5,6].

Linkage distribution: Some branching possible at C(4) [6]. Some fucoidans contain galactose, glucose, mannose, xylose, uronic acid and glucosamine [5]. Short sequences of (→3)-α-L-fuc(2SO₃^-)-(1→4)-α-L-fuc(2,3diSO₃^-)-(1→), DP = 8-14, occurs in the backbone in some fucoidans [8].