new index atom name original index 1 C 14 2 C 10 3 C 19 4 C 13 5 C 12 6 C 11 7 C 18 8 C 16 9 C 17 10 C 15 11 N 5 12 N 9 13 N 7 14 N 8 15 N 6 16 O 1 17 O 2 18 O 4 19 O 3 20 H 30 21 H 31 22 H 25 23 H 26 24 H 32 25 H 29 26 H 28 27 H 27 28 H 22 29 H 23 30 H 24 31 H 20 32 H 21