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