CN(C(=O)c1ccc(NC(=O)Cc2cccc(NC(=O)C3CCCN(C(=O)CCc4ccccc4)C3)c2)cc1)C1CCCC1
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?