Using Br[Mg]C1CCCC1, CC(C)(C)OC(=O)N1C[C@@H]1[C@H]1COC(C)(C)O1 to produce CC(C)(C)OC(=O)N[C@@H](CC1CCCC1)[C@H](O)CO, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.