Using O=C1OC2(c3cc(Cl)c(O)cc3Oc3cc(O)c(Cl)cc32)c2ccccc21 to produce O=C(O)c1ccccc1C1c2cc(Cl)c(O)cc2Oc2cc(O)c(Cl)cc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.