new index atom name original index 1 C 1 2 C 8 3 C 7 4 C 2 5 C 6 6 C 4 7 C 9 8 O 3 9 O 12 10 O 5 11 O 10 12 O 11 13 H 13 14 H 19 15 H 20 16 H 14 17 H 18 18 H 16 19 H 15 20 H 22 21 H 17 22 H 21