O=C(O)C(Cc1c[nH]c2ccccc12)N1C(=O)C2C3c4ccccc4C(c4ccccc43)[C@@H]2C1=O
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?