O(3)-{beta-D-GlcNAc-(1->3)-beta-D-Gal-(1->3)-[beta-D-GlcNAc-(1->6)]-alpha-D-GalNAc}-L-serine residue
o(3)-{beta-d-glcnac-(1->3)-beta-d-gal-(1->3)-[beta-d-glcnac-(1->6)]-alpha-d-galnac}-l-serine residue
An <small>L</small>-α-amino acid residue derived from <em>O</em><small><sup>3</small></sup>-{β-<small>D</small>-GlcNAc-(1→3)-β-<small>D</small>-Gal-(1→3)-[β-<small>D</small>-GlcNAc-(1→6)]-α-<small>D</small>-GalNAc}-<small>L</small>-serine