Using CC(=O)Oc1cc(C(=O)O)ccc1OCC(C)C, CC(C)COc1cccc(OCC(C)C)c1 to produce CC(=O)Oc1cc(C(=O)c2ccc(OCC(C)C)cc2OCC(C)C)ccc1OCC(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.