CCCCC(=O)O[C@@]1(C(=O)CO)C(C)CC2C3CCC4=CC(=O)C=C[C@@]4(C)[C@]3(F)C(O)C[C@]21C
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?