Using CCOC(=O)c1sc2cc(OCc3ccc(Cl)cc3Cl)ccc2c1O, CC(C)(C)OC(=O)CBr to produce CCOC(=O)c1sc2cc(OCc3ccc(Cl)cc3Cl)ccc2c1OCC(=O)OC(C)(C)C, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.