C[C@]12[C@@H]3CC[C@H]1[C@@H](OC(=O)Nc1cc([N+](=O)[O-])cc([N+](=O)[O-])c1)C(=O)N2CC3
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?