COc1ccc(C)c2sc(N(CCN(C)C)C(=O)c3ccc4ccccc4c3)nc12.Cl
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?