CN1CCC23c4c5ccc(O)c4OC2C(=NN=C2CCC4(O)C6Cc7ccc(O)c8c7C4(CCN6C)C2O8)CCC3(O)C1C5
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?