Table 4. Partial spectroscopic details of the four amphidinolide E stereoisomers 1–4.
| C(H) | Synthetic Amphidinolide E (1) | 2-epi-Amphidinolide E (2) | 19-epi-Amphidinolide E (3) | 2-epi-19-epi-Amphidinolide E (4) |
|---|---|---|---|---|
| 2 | 3.26 (1H, m) | 3.35 (1H, q, J = 5.2) | 3.26 (1H, m) | 3.34 (1H, m) |
| 3 | 5.67 (3H, m) 3, 10, & 23 overlap | 6.00 (1H, m) | 5.60 (3H, m) 3, 6, & 10 overlap | 5.98 (1H, m) |
| 4 | 6.19 (2H, m) 4 & 5 overlap | 6.20 (2, m) 4 & 5 overlap | 6.19 (2, m) 4 & 5 overlap | 6.20 (2, m) 4 & 5 overlap |
| 5 | 6.19 (2H, m) | 6.20 (2, m) | 6.19 (2, m) | 6.20 (2, m) |
| 4 & 5 overlap | 4 & 5 overlap | 4 & 5 overlap | 4 & 5 overlap | |
| 6 | 5.53 (1H, dd, J = 14.4, 8.8) | 6.00 (3H, m) 6, 10, & 23 overlap | 5.60 (3H, m) 3, 6, & 10 overlap | 5.63 (2H, m) 6 & 10 overlap |
| 7 | 3.89 (1H, t, J = 8.8) | 3.95 (2H, app dt, J = 8.4, 19.2) 7 & 8 overlap | 3.88 (1H, t, J = 8.8) | 3.96 (2H, m) 7 & 8 overlap |
| 8 | 3.95 (1H, t, J = 8.4) | 3.95 (2H, app dt, J = 8.4, 19.2) 7 & 8 overlap | 3.95 (1H, t, J = 8.4) | 3.96 (2H, m) 7 & 8 overlap |
| 9 | 5.27 (1H, dd, J = 14.4, 7.6) | 5.27 (1H, dd, J = 7.6, 14.4) | 5.27 (1H, dd, J = 8.0, 15.2) | 5.30 (1H, dd, J = 7.6, 15.2) |
| 10 | 5.67 (3H, m) 3, 10, & 23 overlap | 6.00 (3H, m) 6, 10, & 23 overlap | 5.60 (3H, m) 3, 6, & 10 overlap | 5.63 (2H, m) 6 & 10 overlap |
| 13 | 3.40 (1H, m) | 3.43 (1H, m) | 3.40 (1H, m) | 3.42 (1H, m) |
| 16 | 3.56 (1H, m) | 3.50 (1H, m) | 3.56 (1H, app q, J = 8.8) | 3.50 (1H, m) |
| 17 | 3.72 (1H, m) | 3.69 (1H, app t, J = 5.2) | 3.78 (1H, d, J = 7.2) | 3.74 (1H, m) |
| 18 | 4.66 (1H, d, J = 9.2) | 4.66 (1H, d, J = 9.6) | 4.68 (1H, d, J = 10.4) | 4.69 (1H, d, J = 10.4) |
| 22 | 6.05 (1H, d, J = 15.2) | 6.04 (1H, d, J = 16.0) | 6.05 (1H, d, J = 15.6) | 6.05 (1H, d, J = 16.0) |
| 23 | 5.67 (3H, m) 3, 10, & 23 overlap | 6.00 (3H, m) 6, 10, & 23 overlap | 5.87 (1H, dt, J = 6.8, 16.0) | 5.85 (1H, dt, J = 7.2, 15.6) |
| 26a | 4.75 (1H, s) | 4.74 (1H, s) | 4.73 (1H, s) | 4.74 (1H, s) |
| 26b | 4.71 (1H, s) | 4.70 (1H, s) | 4.70 (1H, s) | 4.70 (1H, s) |
| 27 | 1.72 (3H, s) | 1.72 (3H, s) | 1.71 (3H, s) | 1.72 (3H, s) |
| 28a | 4.98 (1H, s) | 4.98 (1H, s) | 4.98 (1H, s) | 4.98 (1H, s) |
| 28b | 4.87 (1H, s) | 4.86 (1H, s) | 4.88 (1H, s) | 4.88 (1H, s) |
| 29 | 0.92 (3H, d, J = 6.8) | 0.91 (3H, d, J = 6.8) | 0.81 (3H, d, J = 6.4) | 0.82 (3H, d, J = 6.8) |
| 30 | 1.25 (3H, d, J = 6.8) | 1.34 (3H, d, J = 7.2) | 1.25 (3H, d, J = 6.8) | 1.34 (3H, d, J = 6.8) |