COc1ccc(O)c2c(=O)c3c(OC)cc4c(c3oc12)[C@@H]1C=CO[C@@H]1O4
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?