CC[C@H](NC(=O)OC(C)(C)C)C(=O)NCP(=O)(OCc1ccc([N+](=O)[O-])cc1)OCc1ccc([N+](=O)[O-])cc1
Hydrogen bond acceptor is the chemical compound which contains the lone electron pairs that participate in the hydrogen bond formation. How many hydrogen bond acceptors does the molecule contain?