Using COC(=O)NC[C@H]1CN(c2ccc(C34CC3CN(C(=O)OC(C)(C)C)C4)cc2)C(=O)O1 to produce COC(=O)NC[C@H]1CN(c2ccc(C34CC3CN(C(=O)OC)C4)cc2)C(=O)O1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.