COc1ccc(-c2oc3ccc(-c4cc(OC)c(OC)c(OC)c4)cc3c2C(=O)c2ccc(OC)nc2)cc1
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?