Using N[C@@H](CCC(=O)O)C(=O)O, CCCCCCCCCCCCCCCC(=O)O to produce CCCCCCCCCCCC(=O)N[C@@H](CCC(=O)O)C(=O)O, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.