Using CSc1nc(C(=O)NC(C)(C)c2ccccc2)c(C(=O)O)s1, O=C([O-])[O-] to produce COC(=O)c1sc(SC)nc1C(=O)NC(C)(C)c1ccccc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.