C[C@H]1CC[C@H]2C(=O)N3[C@@H](CC[C@H](C)[C@H]3c3cccc(N4CCCC4=O)c3)C(=O)N2[C@@H]1c1cccc(N2CCCC2=O)c1
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?