Using Nc1nc2[nH]cc(CCc3ccc(C(=O)N[C@H](CCC(=O)O)C(=O)O)cc3)c2c(=O)[nH]1 to produce Nc1nc2[nH]cc(CCc3ccc(C(=O)N[C@H](CCC(=O)[O-])C(=O)[O-])cc3)c2c(=O)[nH]1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.