Using CC(C)(C)OC(=O)N[C@H]1CC(C(=O)O)=C[C@H]1O, COC(=O)Cl to produce COC(=O)C1=C[C@@H](O)[C@@H](NC(=O)OC(C)(C)C)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.