Nc1ncnc2c1ncn2C1OC(COC2C(CO)OC(OC(C(=O)O)C(O)C(OP(=O)(O)O)C(O)C(=O)O)C(O)C2O)C(O)C1O
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?