COC(=O)C(=O)C(C(=O)C1=NS(=O)(=O)c2cc(S(N)(=O)=O)c(Cl)cc2N1)c1nc2ccc(C(=O)c3ccccc3)cc2nc1O
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?