O=C(Cc1csc2[n+]1C(=O)/C(=C/c1ccc(Cl)cc1)S2)Nc1ccccc1.[Br-]
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?