C[N+]1(C)CCO[C@](O)(c2ccc(-c3ccc([C@]4(O)C[N+](C)(C)CCO4)cc3)cc2)C1
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?