Using C=C(OCC)[Sn](CCCC)(CCCC)CCCC, CCc1cc(Br)ccc1-c1cscn1 to produce CCc1cc(C(C)=O)ccc1-c1cscn1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.