Table 2.
1H-NMR (600 MHz) and 13C-NMR (150 MHz) spectral data of the sugar moieties of swertisin (1) and embinoidin (2) in DMSO-d6 (δ in ppm, J in Hz).
| Position | 1 | 2 | ||
|---|---|---|---|---|
| δC | δH | δC | δH | |
| 6-C-Glc | ||||
| C-1″ | 72.82 a | 4.58 ( d , 10) | 71.02 a | 4.68 ( d , 8.8) |
| 72.58 b | 4.60 ( d , 10) | 70.70 b | 4.70 ( d , 8.8) | |
| C-2″ | 69.62 a | 4.19 ( dt , 10, 2.6) | 80.73 a | 4.47 ( t , 8.8) |
| 70.27 b | 4.00 ( dt , 10, 2.6) | 81.21 b | 4.30 ( t , 8.8) | |
| C-3″ | 79.08 a | 3.18 ( m ) | 78.29 a | 3.42 ( m ) |
| 78.38 b | 3.18 ( m ) | 78.69 b | 3.44 ( m ) | |
| C-4″ | 70.92 a | 3.09 ( m ) | 70.45 a,b | 3.15 ( m) |
| 70.83 b | 3.09 ( m ) | |||
| C-5″ | 81.68 a | 3.16 ( m ) | 81.60 a | 3.16 ( m ) |
| 81.86 b | 3.16 ( m ) | 81.93 b | 3.18 ( m ) | |
| C-6″ | 61.75 a,b | 3.70 ( dd , 12.9, 4.3), | 61.45 a,b | 3.69 ( dd , 13, 4.4), |
| 3.37 ( m ) | 3.38 ( m ) | |||
| 2″-O-Glc | ||||
| C-1‴ | ― | ― | 105.42 a | 4.16 ( d , 8.8) |
| 105.25 b | 4.18 ( d , 8.8) | |||
| C-2‴ | ― | ― | 74.54 a | 2.85 ( dt , 8.8, 2.6) |
| 74.70 b | 2.85 ( dt , 8.8, 2.6) | |||
| C-3‴ | ― | ― | 76.32 a | 3.05 ( m ) |
| 76.37 b | 3.06 ( m ) | |||
| C-4‴ | ― | ― | 69.16 a | 3.02 ( m ) |
| 69.46 b | 2.96 ( m ) | |||
| C-5‴ | ― | ― | 76.42 a | 2.57 ( dt , 8.8, 2.6) |
| 76.68 b | 2.77 ( dt , 8.8, 2.6) | |||
| C-6‴ | ― | ― | 60.07 a | 3.16 ( m), 2.96 (m ) |
| 60.60 b | 3.20 ( m ) | |||
a 13C- and 1H-NMR saccharide signals for one rotamer; b13C- and 1H-NMR saccharide signals for the second rotamer.