Cc1ccc(C(c2c(O)c3ccccc3n(-c3ccccc3)c2=O)c2c(O)c3ccccc3n(-c3ccccc3)c2=O)cc1
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?