C[C@H]([C@@H](N)C(=O)N[C@@H](C(=O)O)[C@@H]1O[C@H](n2ccc(=O)[nH]c2=O)[C@@H](O)[C@H]1O)[C@@H](O)c1ccc(O)cn1
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?