O=C(CN1C(=O)C2C3CC(C(Br)C3Br)C2C1=O)OCC(=O)c1cccc([N+](=O)[O-])c1
Hydrogen bond acceptor: The atom, ion, or molecule component of a hydrogen bond which does not supply the bridging (shared) hydrogen atom. How many hydrogen bond acceptors does the molecule have?