COC(=O)[C@H](Cc1c[nH]c2ccccc12)n1cc(-c2cc(C(=O)N3CCN(C(=O)OC(C)(C)C)CC3)cc(-c3cn([C@@H](CCC(=O)OC(C)(C)C)C(=O)OC(C)(C)C)nn3)c2)nn1
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?