[{"from": "human", "value": "Provide a description of this molecule. [C][C][=Branch1][C][=O][N][C@@H1][C@H1][Branch2][#Branch1][Branch1][C@@H1][Branch1][O][C@H1][Branch1][=Branch1][O][C@H1][Ring1][=Branch1][O][C][O][O][C@H1][C@@H1][Branch2][Branch1][P][C@H1][Branch1][=N][C@H1][Branch1][=Branch2][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C][O][O][O][C@H1][C@@H1][Branch2][Ring2][=Branch1][C@H1][Branch1][=N][C@@H1][Branch1][=Branch2][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C][O][O][O][C@H1][C@@H1][Branch1][P][C@H1][Branch1][=N][C@H1][Branch1][=Branch2][C@H1][Branch1][Ring2][O][Ring1][=Branch1][C][O][O][O][O][N][C][=Branch1][C][=O][C][O][O]"}, {"from": "gpt", "value": "The molecule is a tetrasaccharide comprising residues of galactose, N-acetylglucosamine, galactose and N-acetylglucosamine units in a linear sequence, joined sequentially via beta(1->3), beta(1->3), and beta(1->4) linkages. beta-D-Gal-(1->3)-beta-D-GlcNAc-(1->3)-beta-D-Gal-(1->4)-D-GlcNAc with beta-configuration at the anomeric centre of the reducing-end N-acetylglucosamine residue. It has a role as an epitope."}]