COC(=O)C(Cc1ccc([N+](=O)[O-])cc1)NC(=O)C(CC(=O)OC(C)(C)C)NC(=O)OC(C)(C)C
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?