Using C[C@H]1COCc2nc3cnc4cc(/C=C/S(C)(=O)=O)ccc4c3n21 to produce C[C@H]1COCc2nc3cnc4cc(CCS(C)(=O)=O)ccc4c3n21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.