O=C1OCCN1C(=O)[C@H]1[C@H](c2ccc(Cl)cc2)C(c2cccc(Cl)c2)=NN1c1ccc(Br)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?