C=C1C(=O)O[C@@H]2[C@@H]3O[C@]3(C)C[C@@H]3C=C(C[C@H](OC(=O)C=C(C)C)[C@@H]12)C(=O)O3
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?