CN1C[C@H](C(=O)N[C@@]2(C)O[C@@]3(O)[C@H]4CCCN4C(=O)[C@@H](Cc4ccccc4)N3C2=O)C=C2c3cccc4[nH]cc(c34)C[C@@H]21
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. This compound should contain a more electronegative atom (more electronegative than hydrogen) with lone electron pairs. Then it can attract protons from a donor. Moreover, the electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?