Using Brc1cc(C=Cc2scc3c2OCCO3)ccn1, COC(=O)c1ccnc([Sn](C)(C)C)c1 to produce COC(=O)c1ccnc(-c2cc(C=Cc3scc4c3OCCO4)ccn2)c1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.