O=C(CC1=Nc2nnc(CCCCCCCc3nnc4n3C(=O)C(CC(=O)c3ccc5ccccc5c3)=N4)n2C1=O)c1ccc2ccccc2c1
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?