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