Using COC1=CC(=O)c2ccccc2C1(CCC(C)C)COC(C)=O to produce CC(=O)OCC1(CCC(C)C)C(=O)CC(=O)c2ccccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.