COC(=O)C1=C(C(=O)OC)[C@@H]2N(C)c3ccc(OC)cc3[C@@]23C[C@@H](C(=O)OC)N(C(=O)c2cccs2)C3=N1
The electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?