Table 1. 1H NMR Data (500 MHz or 600 MHz, δ, Hz) for Compounds 1–4 in CDCl3.
| position | 1a,b | 2b | 3c | 4c |
|---|---|---|---|---|
| 2 | 7.76 (s) | 7.87 (s) | 7.76 (s) | 7.87 (s) |
| 5 | 7.85 (s) | 7.86 (s) | ||
| 8 | 6.59 (s) | 6.76 (s) | 6.59 (s) | 6.76 (s) |
| 2′ | 7.14 (d, 2.0) | 7.19 (d, 2.0) | 7.11 (d, 1.8) | 7.17 (d, 1.0) |
| 5′ | 6.93 (d, 8.0) | 6.93 (d, 8.0) | 6.90 (d, 7.8) | 6.90 (d, 8.0) |
| 6′ | 6.97 (dd, 8.0, 2.0) | 7.00 (dd, 8.0, 2.0) | 6.97 (dd, 7.8, 1.8) | 7.00 (br d, 8.0) |
| 1″ | 6.72 (d, 10.0) | 6.43 (d, 10.0) | 6.72 (d, 10.2) | 6.43 (d, 10.0) |
| 2″ | 5.71 (d, 10.0) | 5.73 (d, 10.0) | 5.70 (d, 10.2) | 5.72 (d, 10.0) |
| 4″ | 1.46 (s) | 1.47 (s) | 1.45 (s) | 1.47 (s) |
| 5″ | 1.46 (s) | 1.47 (s) | 1.45 (s) | 1.49 (s) |
| 1‴ | 4.29 (dd, 9.5, 2.5) | 4.30 (dd, 10.0, 2.0) | 4.59 (br d, 6.6) | 4.60 (br d, 6.6) |
| 4.08 (dd, 9.5, 6.5) | 4.09 (dd, 10.0, 5.5) | |||
| 2‴ | 3.69 (br s) | 3.70 (br s) | 5.51 (t, 7.0) | 5.51 (t, 7.0) |
| 4‴ | 1.29 (s) | 1.30 (s) | 1.72(s) | 1.72 (s) |
| 5‴ | 1.24 (s) | 1.29 (s) | 1.75(s) | 1.75(s) |
| 5-OCH3 | 3.86 (s) | 3.87(s) | ||
| 3′-OCH3 | 3.87 (s) | 3.88 (s) | 3.88(s) | 3.89 (3H, s) |
a
Signals were assigned by HMQC, HMBC and 1H–1H COSY experiments.
b
At 500 MHz.
c
At 600 MHz.