Using COC(CCBr)OC, O=c1[nH]cc(-c2cnsc2)c(=O)[nH]1 to produce COC(CCn1cc(-c2cnsc2)c(=O)[nH]c1=O)OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.