O=C1C=CC(=O)c2c1ccc1c3ccccc3n(CCCCCCCCn3c4ccccc4c4ccc5c(c43)C(=O)C=CC5=O)c21
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?