1. (4C) N1 O2 O3 O4 O5 O6 H14 H13 H7 H8 H9 H10 H11 H12 (4F) N1 O2 O3 O4 O5 O6 H13 H14 H7 H8 H9 H10 H11 H12 Supplementary Figure1. Calculated structures of isomers by MP2/aug-cc-pVTZ level of theory. Toshio et al. (4B) N1 O2 O4 O3 O5 O6 H7 H8 H9 H10 H11 H12 H13 H14 (4E) N1 O2 O3 O4 O5 O6 H14 H13 H7 H8 H9 H10 H11 H12

2. (4I) N1 O2 O4 O3 O5 O6 H13 H7 H8 H9 H10 H11 H12 H14 (4K) N1 O2 O4 O3 O5 O6 H7 H8 H9 H10 H11 H12 H13 H14 Supplementary Figure1(continue). Toshio et al. (4M) N1 O2 O4 O3 O5 O6 H7 H8 H9 H10 H11 H12 H13 H14 (4N) N1 O2 O4 O3 O5 O6 H7 H8 H9 H10 H11 H12 H13 H14

3. (4P) N1 O2 O4 O3 O5 O6 H8 H9 H10 H11 H12 H13 H14 H7 (4O) N1 O2 O4 O3 O5 O6 H7 H8 H9 H10 H11 H12 H13 H14 Supplementary Figure1(continue). Toshio et al. (4Q) N1 O2 O4 O3 O5 O6 H8 H9 H10 H11 H12 H13 H14 H7

4. (5B) N1 O2 O3 O4 O5 O6 O7O7 H8H8 H9H9 H10 H11 H12 H13 H14 H15 H16 H17 (5E) N1 O2 O3 O4 O5 O6 O7O7 H14 H8H8 H9H9 H10 H11 H12 H13 H15 H16 H17 Supplementary Figure1(continue). Toshio et al. (5G) N1 O2 O3 O4 O5 O6 O7O7 H15 H16 H17 H14 H8H8 H9H9 H10 H11 H12 H13

5. (5L) N1 O2 O3 O4 O5 O6 O7O7 H8H8 H9H9 H10 H11 H12 H13 H14 H15 H16 H17 (5I) N1 O2 O3 O4 O5 O6 O7O7 H9H9 H10 H11 H12 H13 H8H8 H14 H15 H16 H17 Supplementary Figure1(continue). Toshio et al. (5H) N1 O2 O3 O4 O5 O6 O7O7 H8H8 H9H9 H10 H11 H12 H13 H14 H15 H16 H17 (5K) N1 O2 O7O7 O3 O4 O5 O6 H8H8 H9H9 H10 H11 H12 H13 H14 H15 H16 H17

6. (5P) N1 O2 O4 O3 O5 O6 O7O7 H9H9 H10 H11 H12 H13 H15 H8H8 H16 H17 H14 Supplementary Figure1(continue). Toshio et al.

7. Toshio et al. Supplementary Table1. Calculated electronic energies (E), zero point energies (ZPE), relative energies (  E), and ZPE corrected relative energies (  E+  ZPE) at the MP2/aug-cc-pVTZ//B3LYP/aug-cc-pVDZ and the MP2/aug-cc-pVTZ levels of theory

8. Suplementary Table2. Cartesian Coordinates of all isomers.

9. Suplementary Table2. (continue)

15. Suplementary Table3. Geometrical parameters and natural atomic charges with hydrogen summed into heavy atoms at the MP2/aug-cc-pVTZ level of theory; bond length(r) is given in Å, angles (  and  ) in degrees, and charges (q) in electron units. Toshio et al.