O=[N+]([O-])c1cccc(C2=NN(c3ccccc3)C3c4cc(Br)ccc4OCC23)c1
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. Amide C-N bonds are not counted because of their high barrier to rotation.  How many rotatable bonds does the molecule have?