Nc1ccc(Oc2ccc(C3(c4ccc(Oc5ccc(N)c(O)c5)cc4)C4CC5C6CC7CC5C3C(C7)C6C4)cc2)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?