COc1ccc(COC(=O)N/N=C2/C[C@@H](O)[C@@H](O)[C@@H]3[C@@H]4C(=O)N(Cc5ccc6c(c5)OCO6)C(=O)[C@H]4CC[C@@H]23)cc1
The electronegative atoms usually involved in hydrogen bonding are oxygen, nitrogen and fluorine. How many hydrogen bond acceptors does the molecule contain?