Using COC(=O)C=Cc1ncc(-c2cccc(NCC(=O)OC(C)(C)C)c2)cn1 to produce COC(=O)CCc1ncc(-c2cccc(NCC(=O)OC(C)(C)C)c2)cn1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.