Using COc1cc(OC)nc(S)n1, COC(C)(C)C(OS(C)(=O)=O)C(=O)O to produce COc1cc(OC)nc(SC(C(=O)O)C(C)(C)OC)n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.