Table 2.
13C-NMR (125 MHz) spectral data of xanthones 1–5.
| Position | Compound 1 1 | Compound 2 2 | Compound 3 2 | Compound 4 2 | Compound 5 2 |
|---|---|---|---|---|---|
| 1 | 159.9 | 159.7 | 157.9 | 157.8 | 160.44 |
| 2 | 109.9 | 111.5 | 109.6 | 104.4 | 108.4 |
| 3 | 162.3 | 163.5 | 161.5 | 159.8 | 161.6 |
| 4 | 92.3 | 88.8 | 86.7 | 94.0 | 93.4 |
| 4a | 154.5 | 154.4 | 153.4 | 156.1 | 155.3 |
| 5 | 101.8 | 101.5 | 96.3 | 101.6 | 115.2 |
| 6 | 156.6 | 155.6 | 156.1 | 154.5 | 151.0 |
| 7 | 143.4 | 142.5 | 142.1 | 142.7 | 135.8 |
| 8 | 136.3 | 137.0 | 135.2 | 136.9 | 136.5 |
| 8a | 112.2 | 112.3 | 112.9 | 112.1 | |
| 9 | 181.3 | 181.9 | 180.0 | 181.8 | 182.9 |
| 9a | 103.6 | 103.8 | 102.0 | 103.6 | 117.2 |
| 10a | 154.1 | 155.2 | 153.4 | 155.6 | |
| 11 | 21.3 | 21.3 | 20.4 | 115.6 | 21.4 |
| 12 | 122.4 | 122.3 | 121.6 | 126.9 | 121.4 |
| 13 | 130.3 | 132.0 | 129.6 | 77.8 | 132.6 |
| 14 | 25.5 | 25.8 | 25.8 | 28.3 | 25.8 |
| 15 | 17.9 | 18.2 | 16.3 | 25.6? | 17.9 |
| 16 | 25.6 | 31.2 | 24.1 | 26.5 | 22.6 |
| 17 | 123.7 | 123.2 | 120.5 | 123.1 | 121.0 |
| 18 | 130.3 | 131.7 | 129.7 | 131.8 | 131.3 |
| 19 | 17.7 | 17.8 | 15.8 | 18.1 | 17.9 |
| 20 | 25.7 | 26.7 | 24.1 | ? | 25.8 |
| 3-OMe | − | 55.8 | 54.9 | ||
| 6-OMe | − | − | 53.9 | ||
| 7-OMe | 60.1 | 62.0 | 60.9 | ||
| 8-OMe | 7-OMe | ||||
| 1' | 121.0 | ||||
| 2' | 131.3 | ||||
| 3' | 77.1 | ||||
| 4' | 27.4 | ||||
| 5' | 27.4 |
1 DMSO-d6, 2 CDCl3.