Using CCOC(=O)c1cn(C[C@H]2CC[C@H]3CN(C(=O)OC)[C@H](C(=O)OCC)C[C@H]3C2)cn1 to produce CCOC(=O)c1cn(C[C@H]2CC[C@H]3CN[C@H](C(=O)OCC)C[C@H]3C2)cn1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.