atom_id symbol chemical_shift mult coupling 14 H 4.98 s NA 15 H 4.94 s NA 16 H 4.34 d 4.8 17 H 4.13 d 4.8 18 H 3.66 d 4.8 19 H 3.61 d 4.8 20 H NA NA NA 21 H 4.11 s NA 22 H 4.11 s NA 23 H NA NA NA 24 H 5.78 br s NA 25 H 2.73 dd 10.2,7.8 26 H 2.24 d 10.2 27 H 3.11 d 7.8