COc1cc(C2C(C#N)=C(N)N(c3sc4c(c3C#N)CCCC4)C3=C2C(=O)CC(C)(C)C3)cc(OC)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?