CCOC(=O)CCC(C(=O)OCC)n1nnc2cc(Nc3c(C)[n+]([O-])c4cc(Cl)ccc4[n+]3[O-])ccc21
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?