C[C@@]12C(=O)N(CC3CC3)CC(=O)N1[C@H](/C=C/c1ccccc1)[C@@H]1C(=O)N(c3ccccc3)C(=O)[C@@H]12
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?