Using O=C(O)c1ccc2c(c1)C1(OC2=O)c2ccc(O)cc2Oc2cc(O)ccc21 to produce O=C(O)c1ccccc1-c1c2ccc(=O)cc-2oc2cc(O)ccc12, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.