COC(=O)C1=C(C)N(Cc2ccccc2)C2=C3C(=O)OCCC3[C@@](O)(C(=O)OC)C(=O)N2C1c1ccccc1
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?