CC[C@H](C)[C@@H]1NC(=O)c2cc([N+](=O)[O-])cc(I)c2SC[C@@H](C(N)=O)NC(=O)[C@H](CCCCN)NC1=O
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?