Using C[O-], Cc1cc2nc(Cl)sc2c(Br)c1[C@@H](COC(=O)C(C)(C)C)OC(C)(C)C to produce COc1nc2cc(C)c([C@@H](COC(=O)C(C)(C)C)OC(C)(C)C)c(Br)c2s1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.