COc1ccc2cc1Oc1ccc(cc1)C[C@@H]1c3c(cc(OC)c4c3Oc3cc5c(cc3O4)CCN[C@H]5C2)CCN1C
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. This compound should contain a more electronegative atom (more electronegative than hydrogen) with lone electron pairs. Then it can attract protons from a donor. Moreover, the electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?