COc1cccc([C@@H]2Oc3ccc(OC)cc3/C(=N/O[C@@H](C)CN3CCCCc4nc(C)c(C)cc43)[C@@H]2O)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?