O=C1CCc2cc(S(=O)(=O)NCCC(=O)NC3CCN(Cc4ccccc4)CC3)ccc2N1
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?