Using Cc1noc(NS(=O)(=O)c2ccsc2C(N)=O)c1Br, O=C(O)c1ccc2c(c1)OCO2 to produce Cc1noc(NS(=O)(=O)c2ccsc2C(=O)NC(=O)c2ccc3c(c2)OCO3)c1Br, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.