Using CC(=O)OC(C)(C)C, COC(=O)c1cnc(NC(=O)C(C)(C)C)cn1 to produce CC(C)(C)OC(=O)CC(=O)c1cnc(NC(=O)C(C)(C)C)cn1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.