O=C(CSc1nnc(NC2CCCCC2)s1)Nc1ccc2c(c1)C(=O)c1ccccc1C2=O
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?