Using CCOC(=O)CC1CCc2c1[nH]c1ccc(OCc3ccc(-c4csnn4)cc3)cc21 to produce O=C(O)CC1CCc2c1[nH]c1ccc(OCc3ccc(-c4csnn4)cc3)cc21, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.