COc1cc(O)c2c(=O)c3c(O[C@H]4O[C@@H](CO)[C@H](O)[C@@H](O)[C@@H]4O)ccc(O)c3oc2c1
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?