atom_id symbol chemical_shift mult coupling 16 H 2.03 d 7.2 17 H 2.03 d 7.2 18 H 2.03 d 7.2 19 H 7.05 q 7.2 20 H 6.02 dd 3.9,2.7 21 H 2.26 dt 13.8,2.7 22 H 2.12 ddd 13.8,1.8,3.9 23 H 3.95 m NA 24 H NA NA NA 25 H 7.63 s NA