Table 2.
1H chemical shift (δ, ppm) of sildenafil citrate and sildenafil base in dimethyl sulfoxide-d6
| Signal number | Functional group | Position number | δ 1H | Multiplicity | |
|---|---|---|---|---|---|
|
| |||||
| Sildenafil citrate | Sildenafil base | ||||
| I | –CH3 | 13 | 0.95 | 0.95 | Triplet |
| II | –CH2 | 21 | 1.18 | 1.19 | Triplet |
| IV | –CH2 | 12 | 1.54 | 1.54 | Sextuplet |
| IV | –CH2 | 11 | 2.84 | 2.86 | Triplet |
| V | –CH3 | 10 | 3.72 | 3.75 | Singlet |
| VI | Ring C | Ring C | 7.07 | 7.11 | Doublet of doublet |
| VII | Ring C | Ring C | 7.30 | 7.34 | Doublet |
| VII | Ring C | Ring C | 7.40 | 7.42 | Doublet |
| DMSO | - | - | 2.50 | 2.50 | Singlet |
DMSO: Dimethyl sulfoxide