N/N=C(\C(=O)Nc1c(Cl)cc([N+](=O)[O-])cc1Cl)C(c1cnc2ccc([N+](=O)[O-])cc2n1)[N+](=O)[O-]
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?