Using CCOC(CCNC(Nc1ccsc1)=C1C(=O)OC(C)(C)OC1=O)OCC to produce CCOC(CCNc1[nH]c2ccsc2c(=O)c1C(=O)O)OCC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.