Using CC(=O)OC(C)=O, CC[C@]12C[C@H](Cl)[C@H]3[C@@H](CCC4=CC(=O)CC[C@@H]43)[C@@H]1[C@@H](O)CC2=O to produce CC[C@]12C[C@@H](Cl)[C@H]3[C@@H](CCC4=CC(=O)CC[C@@H]43)[C@@H]1[C@@H](OC(C)=O)CC2=O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.