COC(=O)c1c(N2C(=O)[C@@H]3[C@@H]4CCCN4[C@@]4(C(=O)Nc5c(C)cccc54)[C@@H]3C2=O)sc(C)c1C
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?