O=c1c2ccccc2oc2cc(O)c([C@@H]3COC[C@@H](CO)[C@@H](O)[C@@H](O)[C@H]3O)c(O)c12
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?