Using O=C(NC1CC(CN2CCC(CCCc3ccccc3)CC2)C(c2ccccc2)C1)OCc1ccccc1 to produce NC1CC(CN2CCC(CCCc3ccccc3)CC2)C(c2ccccc2)C1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.