Using CC1(C)O[C@H](CC#N)C[C@H](CC(=O)O)O1, CC(C)(C)O to produce CC(C)(C)OC(=O)C[C@H]1C[C@@H](CC#N)OC(C)(C)O1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.