CO[C@]1(Nc2ccc(C=O)cc2)C(=O)c2ccccc2O[C@]1(OC)c1ccc([N+](=O)[O-])cc1
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?