O=C(OCC1OC2OC(c3ccccc3)(n3ccc4c([N+](=O)[O-])ccnc43)OC2C1OC(=O)c1ccccc1)c1ccccc1
A rotatable bond is defined as any single non-ring bond, attached to a non-terminal, non-hydrogen atom. How many bonds in the molecule are rotatable?