Using COC(=O)[C@@H](Nc1nc(-c2ccc(Br)cc2)cs1)C(F)(F)F to produce OCC(Nc1nc(-c2ccc(Br)cc2)cs1)C(F)(F)F, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.