C=C1[C@]2(C)C=C(C)[C@@H](n3c(=O)n(-c4ccccc4)c(=O)n32)[C@]1(C)[C@@H]1CCCS1
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?