TABLE 2
Proton (1H NMR) and carbon chemical shifts (13C NMR for parent and heteronuclear multiple quantum coherence for conjugates) of compound 1 and its two GSH conjugates (GSH1-2 and GSH1-3)
The proposed structure of GSH1-3 (Z) is shown below. The numbering system is for illustrative purposes only.
| δH ppm | δC ppm | ||||||
|---|---|---|---|---|---|---|---|
| Position | Compound 1 | GSH1-2 | GSH1-3 | Compound 1 | GSH1-2 | GSH1-3 | |
| 3 | 8.52 | ND | ND | ||||
| 4 | 5.00 | 4.95 | 5.00 | 60.9 | 61.8 | 61.7 | |
| 5 | 5.54 | 5.45 | 5.50 | 82.8 | 83.2 | 83.1 | |
| 7 | 7.24 | 7.26 | 7.23 | 122.6 | 123.4 | 122.9 | |
| 8 | 7.44–7.58 | 7.55 | 7.45–7.55 | 132.0 | 131.8 | 131.6 | |
| 9 | 7.26–7.37 | 7.26 | 7.25 | 116.9 | 116.6 | 116.4 | |
| 11 | 7.26–7.37 | 7.30 | 7.35 | 113.6 | 113.8 | 113.6 | |
 | 13 | 8.59 | 8.38 | 8.47 | 148.9 | 147.7 | 148.6 |
| 15 | 8.86 | 8.87 | 8.72 | 140.2 | 151.0 | 140.2 | |
| 17 | 8.14 | 8.23 | 7.94 | 138.5 | 138.2 | 134.5 | |
| 20 | NA | 7.60a | NA | 88.55 | 134.2a | NA | |
| 21 | NA | 7.01 | 89.36 | 127.7 | |||
| 23 | 8.95 | 9.10 | 8.92 | 147.9 | 144.2 | 146.2 | |
| 25 | 8.73 | 8.75 | 8.50 | 143.9 | 144.4 | 142.2 | |
| 26 | 8.69 | 8.65 | 8.72 | 146.2 | 144.6 | 144.0 | |
NA, not applicable; ND, not detected.
↵a The site could not be assigned because HMBC and ROESY spectra could not be acquired