O=c1c2cc(S(=O)(=O)O)ccc2nc(COc2ccc(Oc3ccc(Cl)cc3Cl)cc2)n1-c1ccc(Cl)cc1Oc1c(Cl)cccc1Cl
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?