O=C1N[C@@H](Cc2ccccc2)C(=O)N2[C@H]1CC1([C@]34C[C@H]5C(=O)N[C@@H](Cc6ccccc6)C(=O)N5[C@H]3Nc3ccccc34)c3ccccc3N[C@H]21
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?