new index atom name original index 1 C 8 2 C 6 3 C 7 4 C 9 5 C 10 6 N 5 7 O 1 8 O 3 9 O 2 10 O 4 11 H 13 12 H 14 13 H 15 14 H 11 15 H 12 16 H 16 17 H 17 18 H 18 19 H 19