Table 1.
1H NMR, 13C NMR, and 15N NMR of etamycin (each rotamer) in CDCl3.
| rotamer 1 (major) | rotamer 2 | rotamer 3 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| δN | δCa | δH (m, J (Hz)) | δCa | δH | δCa | δH | |||
| Phg | 1 | 169.6 | C | 169.5 | 169.5 | ||||
| 2 | 62.8 | CH | 5.66 (s) | 61.6 | 5.96 | 63.2 | 5.60 | ||
| 3 | 130.3 | C | 130.9 | 130.4 | |||||
| 4, 8 | 129.7 | CH | 7.41 (m) | 129.4 | 7.46 | 129.4 | 7.36 | ||
| 5, 7 | 129b | CH | 7.4b | 129b | 7.4b | 129b | 7.4b | ||
| 6 | 129b | CH | 7.4b | 129b | 7.4b | 129b | 7.4b | ||
| 2-NCH3 | 182.5 | 31.8 | CH3 | 2.80 (s) | 31.4 | 2.87 | 32.4 | 2.78 | |
| Ala | 9 | 173.5 | C | 174.1 | 173.2 | ||||
| 10 | 45.8 | CH | 5.05 (m) | 45.3 | 5.10 | 46.2 | 4.98 | ||
| 11 | 17.9 | CH3 | 1.39 (d, 6.6) | 16.5 | 1.40 | 18.1 | 1.28 | ||
| 10-NH | 179.5 | 7.26 | 7.93 | 7.48 | |||||
| β-MeLeu | 12 | 168.9 | C | 168.4 | 167.2 | ||||
| 13 | 58.4 | CH | 5.09 (d, 10.3) | 62.8 | 3.77 | 61.9 | 3.93 | ||
| 14 | 35.4 | CH | 2.21 (m) | 37.1 | 2.26 | 36.2 | 2.35 | ||
| 15 | 28.3 | CH | 1.80 (m) | 27.3 | 1.51 | 27.2 | 1.61 | ||
| 16 | 15.4 | CH3 | 0.77 (d, 7.1) | 15.8 | 0.79 | 15.3 | 0.81 | ||
| 17 | 21.5 | CH3 | 0.94 (d, 6.2) | 21.9 | 0.90 | 21.6 | 0.95 | ||
| 18 | 8.5 | CH3 | 0.60 (d, 7.1) | 8.5 | 0.75 | 8.4 | 0.71 | ||
| 13-NCH3 | 195.5 | 30.0 | CH3 | 2.82 (s) | 29.3 | 2.93 | 28.6 | 2.91 | |
| Gly | 19 | 167.5 | C | 167.8 | 167.7 | ||||
| 20a | 52.3 | CH2 | 3.87 (d, 16.8) | 50.5 | 3.40 | 52.3 | 3.87 | ||
| 20b | 5.34 (d, 16.8) | 5.39 | 6.03 | ||||||
| 20-NCH3 | 192.5 | 35.6 | CH3 | 2.92 (s) | 33.3 | 3.21 | 36.4 | 3.02 | |
| Hyp | 21 | 173.9 | C | 173.3 | 173.7 | ||||
| 22 | 53.9 | CH | 5.17 (d, 6.1) | 55.2 | 4.82 | 56.6 | 4.53 | ||
| 23a | 37.4 | CH2 | 2.05 (d, 13.7) | 35.4 | 1.94 | 37.0 | 2.13 | ||
| 23b | 2.15 (m) | 2.26 | |||||||
| 24 | 70.8 | CH | 4.52 (m) | 71.3 | 4.44 | 70.5 | 4.38 | ||
| 25a | 58.1 | CH2 | 3.72 (dd, 5.6, 11.3) | 56.0 | 3.81 | 57.9 | 3.73 | ||
| 25b | 4.42 (dd, 5.8, 11.3) | 3.82 | |||||||
| 24-OH | 6.68 (d, 11.5) | 5.44 | 6.52 | ||||||
| 22-N | 167.5 | ||||||||
| Leu | 26 | 172.0 | C | 171.5 | 170.9 | ||||
| 27 | 49.0 | CH | 4.89 (m) | 48.9 | 5.02 | 48.8 | 5.03 | ||
| 28a | 39.4 | CH2 | 1.48 (ddd, 4.4, 9.0, 13.4) | 39.4 | 1.38 | 40.8 | 1.61 | ||
| 28b | 1.91 (m) | 2.14 | 1.80 | ||||||
| 29 | 24.2 | CH | 1.85 (m) | 24.2 | 1.87 | 24.1 | 1.69 | ||
| 30 | 21.0 | CH3 | 0.93 (d, 6.4) | 20.6 | 1.01 | 21.5 | 0.95 | ||
| 31 | 23.0 | CH3 | 0.98 (d, 7.0) | 23.3 | 0.99 | 23.2 | 0.94 | ||
| 27-NH | 174.5 | 8.33 (d, 8.5) | 8.15 | 7.84 | |||||
| Thr | 32 | 165.9 | C | 166.1 | 165.9 | ||||
| 33 | 53.0 | CH | 4.88 (m) | 53.4 | 4.84 | 53.0 | 4.93 | ||
| 34 | 70.0 | CH | 5.17 (m) | 69.7 | 5.25 | 70.0 | 5.27 | ||
| 35 | 13.4 | CH3 | 1.17 (d, 6.8) | 13.5 | 1.22 | 13.9 | 1.20 | ||
| 33-NH | 199.0 | 8.93 (d, 7.5) | 9.02 | 8.95 | |||||
| Hpca | 36 | 167.7 | C | 167.8 | 168.1 | ||||
| 37 | 130.8 | C | 130.8 | 130.6 | |||||
| 38 | 157.3 | C | 157.3 | 157.3 | |||||
| 39 | 125.6 | CH | 7.25 (m) | 125.6 | 7.25 | 125.7 | 7.27 | ||
| 40 | 128.5 | CH | 7.30 (m) | 128.5 | 7.29 | 128.7 | 7.3b | ||
| 41 | 139.6 | CH | 8.07 (d, 3.9) | 139.6 | 8.04 | 139.8 | 8.09 | ||
| 38-OH | 11.77 (s) | 11.74 | 11.67 | ||||||
| 41-N | 197.5 | ||||||||
a
13C shifts obtained from HMBC and HSQC spectra.
b
Overlapping peaks.