COc1c2cc(C(C)(C)C)cc1Cc1cccc(c1O)Cc1cc(C(C)(C)C)cc(c1OC)Cc1cccc(c1O)Cc1cc(C(C)(C)C)cc(c1OC)Cc1cccc(c1O)C2
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?