C[n+]1c2n(c3ccccc31)N=C(c1cc(C(C)(C)C)c(O)c(C(C)(C)C)c1)CS2.[Br-]
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?