Table 3.
1H NMR data for gemmacolides AG-AL (7–12) a.
| Position | 7 | 8 | 9 | 10 | 11 | 12 |
|---|---|---|---|---|---|---|
| 2 | 5.61, ov | 5.67, ov | 5.78, d (9.9) | 5.58, d (9.9) | 5.7, d (9.9) | 5.64, d (9.7) |
| 3 | 5.61, ov | 5.62, dd (10.0, 9.9) | 5.61, dd (9.9, 10.3) | 5.60, dd (10.1, 9.9) | 5.6, dd (9.9, 10.3) | 5.60, dd (9.7, 9.8) |
| 4 | 6.29, br s | 6.34, d (10.4) | 6.32, d (10.3) | 6.40, d (10.1) | 6.40, d (10.3) | 6.33, d (9.8) |
| 6 | 5.71, d (8.6) | 5.69, ov | 5.65, ov | 6.06, d (8.4) | 5.9, d (8.6) | 5.89, d (8.7) |
| 7 | 4.97, d (8.6) | 4.96, d (9.0) | 4.96, ov | 4.95, d (8.4) | 4.99, d (8.6) | 4.98, d (8.7) |
| 9 | 4.74, d (4.4) | 4.74, d (4.7) | 4.74, d (4.8) | 4.74, d (4.7) | 4.74, d (4.8) | 4.75, d (4.5) |
| 10 | 3.61, ov | 3.61, d (4.7) | 3.6, ov | 3.59, ov | 3.62, d (4.8) | 3.62, d (4.5) |
| 12 | 4.86, br s | 4.91, d (3.0) | 3.45, br s | 4.91, d (3.2) | 4.9, d (3.4) | 4.89, d (3.1) |
| 13β | 5.08, dd (3.0, 2.8) | 5.08, dd (3.0, 2.8) | 4.97, ov | 5.08, dd (3.3, 3.2) | 5.08, dd (3.4, 3.5) | 5.09, dd (3.1, 3.0) |
| 14 | 5.22, br s | 5.20, d (2.8) | 5.30, br s | 5.18, d (3.3) | 5.16, d (3.5) | 5.17, d (3.0) |
| 15 | 1.14, s | 1.13, s | 1.13, s | 1.13, s | 1.13, s | 1.13, s |
| 16a | 5.45, d (15.6) | 5.42, d (15.6) | 5.46, d (15.6) | 4.68, d (16.2) | 4.5, d (14.7) | 4.53, d (15.3) |
| 16b | 4.64, d (15.6) | 4.59, d (15.6) | 4.56, d (15.6) | 4.45, ov | 4.25, d (14.7) | 4.11, d (15.3) |
| 17 | 2.31, q (7.0) | 2.30, q (6.9) | 2.28, q (6.9) | 2.30, q (7.0) | 2.31, q (6.9) | 2.29, q (6.9) |
| 18 | 1.15, d (7.0) | 1.13, d (6.9) | 1.13, d (6.9) | 1.14, d (7.0) | 1.15, d (6.9) | 1.15, d (6.9) |
| 20a | 3.61, ov | 3.60, ov | 3.60, br s | 3.59, ov | 3.60, d (2.6) | 3.60, d (2.1) |
| 20b | 2.92, br s | 2.93, d (2.2) | 2.76, d (2.1) | 2.93, d (1.4) | 2.97, d (2.6) | 2.92, d (2.1) |
| 9-OAc | 2.19, s | 2.19, s | 2.19, s | 2.18, s | 2.19, s | 2.18, s |
| R1 | 1.95, s | 4.52, d (15.6) | 4.52, d (15.6) | 4.54, d (15.7) | 4.15,d (16.9) | 4.53, d (15.7) |
| 4.43, d (15.6) | 4.42, d (15.6) | 4.44, d (15.7) | 4.0, d (16.9) | 4.43, d (15.7) | ||
| 2.28, ov (×2) | 2.28, ov (×2) | 2.29, ov (×2) | 2.28, ov (×2) | |||
| 2.16, m | 2.13, m | 2.13, m | 2.15, ov | |||
| 0.98, ov (×2) | 0.99, d (6.5) (×2) | 0.98, ov (×2) | 0.98, ov (×2) | |||
| R2 | 2.16, s | 2.35, ov (×2) | 2.32, ov | 2.16, s | 2.14, s | |
| 2.23, ov | ||||||
| 2.16, m | 2.17, m | |||||
| 0.98, ov (×2) | 1.00, ov (×2) | |||||
| R3 | 1.95, s | 1.94, s | 2.03, s | 1.94, s | 2.2, ov | 2.09, ov (×2) |
| 2.08, ov | 1.99, ov | |||||
| 1.97, m | 0.92, d (6.5) | |||||
| 0.9, d (6.5) (×2) | 0.91, d (6.5) | |||||
| R4 | 2.10, s | 2.10, s | 2.13, s | 2.07, s | 2.06, s | 2.05, s |
| R5 | 2.3, ov (×2) | 2.26, ov (×2) | 2.28, ov (×2) | 3.45, s | 3.44, s | |
| 2.05, m | 2.16, m | 2.13, m | ||||
| 0.99, d (6.6) (×2) | 0.98, ov (×2) | 0.99, d (6.6) (×2) |
a 400 MHz, in CDCl3, assignments made by DEPT, 1H-1H COSY, HSQC, and HMBC; “ov” means overlapped signals.