Cn1c(=O)n(C)c2cc(NS(=O)(=O)c3ccc(Br)cc3)c(NCc3ccccc3)cc21
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?