O=C1C2C3C=CC([C@@H]2C(=O)N1C1CCCCC1)[C@H]1C(=O)N(C2CCCCC2)C(=O)C31
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?