Cc1ccc2c(=O)n3c(nc2c1)C(Cc1ccccc1)NC(=O)c1cc2ccccc2cc1-3
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?