COc1ccc([C@H]2[C@H](C(=O)C(C)(C)C)N3N=Cc4ccccc4C3[C@]23N=C(c2ccccc2)OC3=O)cc1OC
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?