COc1ccccc1C(O)[C@@H]1C[C@@H]2[C@H]3CC[C@@](C)([C@@H]2O1)C3(C)C
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?