Table 3.
1H and 13C NMR (500 and 125 MHz, 300K) assignments of the C-13 glycosides of compound 1 in pyridine-d5.
| Sugar | Atom No. | 13C NMR | 1H NMR |
|---|---|---|---|
| Glc II | 1 | 96.6 | 5.42 d (8.0) |
| 2 | 81.2 | 4.19 m | |
| 3 | 88.6 | 4.93 m # | |
| 4 | 70.5 or 70.6 or 70.7 | 4.09 m | |
| 5 | 78.0–78.5 ¥ | 3.88 m | |
| 6 | 62.2–63.4 ¥ | 4.19 m or 4.22 m, 4.33 m | |
| Glc III | 1 | 104.8 | 5.48 d (7.4) |
| 2 | 75.9 or 76.0 | 4.11 m | |
| 3 | 78.7–79.0 ¥ | 4.13 m | |
| 4 | 74.3 | 3.87 m | |
| 5 | 76.5 | 3.97 m | |
| 6 | 72.1 | 4.44 m, 4.50 m | |
| Glc IV | 1 | 104.3 | 5.40 d (8.0) |
| 2 | 75.9 or 76.0 | 3.97 m | |
| 3 | 78.7–79.0 ¥ | 4.47 m | |
| 4 | 71.5 or 71.6 | 4.13 m or 4.15 m | |
| 5 | 78.0–78.5 ¥ | 3.97 m | |
| 6 | 62.2–63.4 ¥ | 4.19 m or 4.22 m, 4.32 m | |
| Glc VII | 1 | 100.6 | 5.76 d (3.5) |
| 2 | 81.4 | 4.13 m | |
| 3 | 84.7 | 4.60 m | |
| 4 | 70.5 or 70.6 or 70.7 | 4.16 m | |
| 5 | 74.0 | 4.41 m | |
| 6 | 62.2–63.4 ¥ | 4.36 m, ~4.5 m | |
| Glc VIII | 1 | 106.5 | 5.10 d (7.7) |
| 2 | 75.7 | 4.06 m | |
| 3 | 78.7–79.0 ¥ | 4.17 m | |
| 4 | 72.1 or 74.0 | 4.10 m or 4.16 m | |
| 5 | 78.7–79.0 ¥ | 3.81 m or 3.85 m | |
| 6 | 62.2–63.4 ¥ | ~4.2 m to ~4.5 m | |
| Glc IX | 1 | 105.4 | 5.06 d (7.8) |
| 2 | 76.1 | 3.98 m | |
| 3 | 78.7–79.0 ¥ | 4.13 m | |
| 4 | 72.1 or 74.0 | 4.10 m or 4.16 m | |
| 5 | 78.7–79.0 ¥ | 3.81 m or 3.85 m | |
| 6 | 62.2–63.4 ¥ | ~4.2 m to ~4.5 m |
¥ Chemical shifts could not be unequivocally assigned due to very close chemical shifts or overlapping resonances. # Proton resonance obscured by the water resonance, assignment based on 1D Total Correlation Spectroscopy (TOCSY) and 2D NMR data.