C[C@H](CCC(=O)NCC(=O)O)[C@H]1CC[C@H]2[C@@H]3[C@@H](O)C[C@H]4C[C@@H](O)CC[C@@]4(C)[C@@H]3C[C@@H](O)[C@@]21C
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?