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