Using C=C(OCC)[SnH2]CCCC, Brc1cnc2nnn(Cc3ccc4ncccc4c3)c2n1 to produce C=C(OCC)c1cnc2nnn(Cc3ccc4ncccc4c3)c2n1, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.