Table 1.
1H and 13C NMR Data of Amyrisins A–C (1 – 3) in CDCl3
| Position | 1 | 2a | 3a | |||
|---|---|---|---|---|---|---|
| 13C | 1H | 13C | 1H | 13C | 1H | |
| 2 | 164.4 | 164.1 | 164.1 | |||
| 3 | 103.9 | 6.58 s | 103.9 | 6.58 s | 103.9 | 6.96 s |
| 4 | 183.1 | 182.7 | 6.60 s | 182.7 | ||
| 5 | 152.3 | 152.3 | nd | |||
| 6 | 130.5 | 130.4 | 130.1 | |||
| 7 | 155.0 | 155.1 | 155.0 | |||
| 8 | 93.4 | 6.60 s | 93.4 | 6.60 s | 93.4 | 6.98 s |
| 9 | 153.3 | 153.8 | 153.1 | |||
| 10 | 105.9 | 105.7 | 105.8 | |||
| 1′ | 123.6 | 124.5 | 123.5 | |||
| 2′ | 128.2 | 7.83 d, 9.0 | 128.3 | 7.84 d, 9.0 | 108.8 | 7.22, d, 2.1 |
| 3′ | 115.4 | 7.03 d, 9.0 | 115.1 | 7.05 d, 9.0 | 149.6 | |
| 4′ | 162.1 | 161.7 | 151.6 | |||
| 5′ | 115.4 | 7.03 d, 9.0 | 115.1 | 7.05 d, 9.0 | 112.7 | 6.97 d, 8.6 |
| 6′ | 128.2 | 7.83 d, 9.0 | 128.3 | 7.84 d, 9.0 | 120.1 | 7.49 dd, 8.5, 2.1 |
| 1″ | 65.3 | 4.60 d, 6.5 | 71.9 | 4.14 dd, 9.5, 3.2 4.04 t, 9.2 |
66.1 | 4.67 d, 6.6 |
| 2″ | 119.1 | 5.51 t, 6.5 | 74.1 | 4.53 m | 119.3 | 5.52 t, 6.6 |
| 3″ | 139.2 | 143.3 | 138.7 | |||
| 4″ | 18.4 | 1.78 s, 3H | 113.3 | 5.19 s 5.06 s |
18.0 | 1.77 s |
| 5″ | 26.0 | 1.83 s, 3H | 18.7 | 1.86 s, 3H | 25.5 | 1.80 s |
| OCH3-6 | 61.0 | 4.05 s, 3H | 60.7 | 4.05 s, 3H | 61.0 | 4.05 s |
| OCH3-3′ | 56.3 | 3.96 s | ||||
| OH-5 | 13.12 s | 13.01 s | 13.09 s | |||
| OH-7 | 6.49 brs | 6.49 s | ||||
a
13C NMR data were obtained from the HSQC and HMBC spectra due to the small quantity of material available, nd = not detected.