Using CCOC(=O)c1c(NC(C)=O)sc2c1CCCC2, O=S(=O)([O-])[O-] to produce CCOC(=O)c1c(NC(C)=O)sc2c1CCCC2=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.