CCCn1c(=O)c(C(=O)Nc2c(C)n(C)n(-c3ccccc3)c2=O)c(O)c2ccccc21
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?