O=C(c1ccccc1)N(C(=O)c1ccccc1)c1ncnc2c1C(c1ccccc1)c1c(ccc3ccccc13)O2
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?