Using CC[Mg]Br, CCOC(=O)c1sc(N(C(=O)OC(C)(C)C)C(=O)OC(C)(C)C)nc1C=O to produce CCOC(=O)c1sc(N(C(=O)OC(C)(C)C)C(=O)OC(C)(C)C)nc1C(O)CC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.