CC(C)=CCc1cc(C2COc3cc4c(c(O)c3C2=O)C=CC(C)(C)O4)c(O)cc1O
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?