Using CCOC=O, O=C(O)CCCc1ccc2c(c1)Cc1cccc(C(=O)O)c1-2 to produce O=CC1c2cc(CCCC(=O)O)ccc2-c2c(C(=O)O)cccc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.