C2H4O3\mathrm{C}_{2} \mathrm{H}_{4} \mathrm{O}_{3}C2H4O3
C2H2O\mathrm{C}_{2} \mathrm{H}_{2} \mathrm{O}C2H2O
C4H6O4\mathrm{C}_{4} \mathrm{H}_{6} \mathrm{O}_{4}C4H6O4
C3H6O3\mathrm{C}_{3} \mathrm{H}_{6} \mathrm{O}_{3}C3H6O3
None