COc1ccc2[nH]cc([C@@H]3C4CCC(C4)[C@H]3NCc3cccc(CN[C@H]4C5CCC(C5)[C@@H]4c4c[nH]c5ccc(OC)cc45)c3)c2c1
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?