preferred_name: a 3-O-{beta-D-galactosyl-(1->3)-[N-acetyl-beta-D-glucosaminyl-(1->6)]-N-acetyl-alpha-D-galactosaminyl}-L-threonyl-[protein] + 3'-phosphoadenylyl sulfate => 3-O-{beta-D-galactosyl-(1->3)-[6-O-sulfo-N-acetyl-beta-D-glucosaminyl-(1->6)]-N-acetyl-alpha-D-galactosaminyl}-L-threonyl-[protein] + adenosine 3',5'-bisphosphate + H(+)