Using COCCOCCBr, COC(=O)c1n[nH]c(C(=O)OC)c1[N+](=O)[O-] to produce COCCOCCn1nc(C(=O)OC)c([N+](=O)[O-])c1C(=O)OC, please predict the agent for this reaction in SMILES notation in \boxed{$SMILES1, SMILES2, ...} format.