O=C(COC(=O)c1cc(S(=O)(=O)Nc2ccccc2Cl)ccc1O)Nc1nc2ccccc2s1
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?