Cc1cnc(NC(=O)C2=C([O-])c3ccccc3S(=O)(=O)N2C)s1.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?