CN(C)CCNc1ccc(C(=O)NCCCN(C)CCCNC(=O)c2ccc(NCCN(C)C)c3c(=O)c4ccccc4[nH]c23)c2[nH]c3ccccc3c(=O)c12.Cl
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?