COc1cc(C2C(C(=O)Nc3ccc(Cl)c(Cl)c3)=C(C)NC(C)=C2C(=O)Nc2ccc(Cl)c(Cl)c2)ccc1O
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?