COc1ccc(O[C@H]2C=C[C@@H](c3ccccc3)O[C@H]2COC(=O)CC/C(C)=N\O[C@@H](C)CN2CCCCc3nc(C)c(C)cc32)cc1
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?