CCCCCCCCCCCCCCCC(=O)OCC1OC(N2C(=O)/C(=N\NC(N)=S)c3ccc([N+](=O)[O-])cc32)C(OC(C)=O)C1OC(C)=O
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?