C=C1C[C@@]23C[C@]1(O)CC[C@@H]2[C@]12C=C[C@@H](O)[C@](C)(C(=O)O1)[C@H]2[C@H]3C(=O)O
The electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?