CC(C)(C)OC(=O)[C@H]1[C@H](c2ccc([N+](=O)[O-])cc2)C2(C(=O)c3ccccc3C2=O)C2c3ccccc3C=NN21
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?