COC(=O)[C@H](CO)n1cc(-c2cc(C(=O)N3CCN(C(=O)OC(C)(C)C)CC3)cc(-c3cn([C@@H](CCC(=O)OC(C)(C)C)C(=O)OC(C)(C)C)nn3)c2)nn1
Molecules possible for drug usually have no more than 5 Hydrogen bond acceptor. How many hydrogen bond acceptors does the molecule have?