Using COC(=O)c1cccc(Cn2cc(C3c4ccccc4C=Cc4ccccc43)c(=S)[nH]c2=O)n1 to produce O=C(O)c1cccc(Cn2cc(C3c4ccccc4C=Cc4ccccc43)c(=S)[nH]c2=O)n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.