C[C@]12c3[nH]c4ccccc4c3CCN1C(=O)C(CC(=O)NCC13C[C@H]4C[C@@H](C1)C[C@@H](C3)C4)C[C@@H]2C(=O)N1CCOCC1
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. How many hydrogen bond acceptors does the molecule contain?