Using CCOC(=O)CCCCCCCCCCOc1ccc(OC(C)=O)cc1, CCOC(=O)OCC to produce CCOC(=O)CCCCCCCCCCOc1ccc(OC(=O)CC(=O)OCC)cc1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.