C[C@@H](C(=O)N1CCN(C(=O)OC(C)(C)C)CC1)n1cc(-c2cn([C@@H](C)C(=O)N3CCN(C(=O)OC(C)(C)C)CC3)nn2)nn1
Hydrogen bond acceptor: The atom, ion, or molecule component of a hydrogen bond which does not supply the bridging (shared) hydrogen atom. How many hydrogen bond acceptors does the molecule have?