C=Cc1cc(OC)c2c(c1)c(=O)oc1c2cc(OC)c2c(O)ccc(C3OC(C)C(O)C(C)(O)C3O)c21
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?