NC(Cc1cc(I)c(Oc2ccc(O)c(I)c2)c(I)c1)C(=O)[O-].[Na+]
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?