COc1cccc(C2C(C(=O)c3c(C)nc4c(C)cccn34)=C(O)C(=O)N2CCCN(C)C)c1OC
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?