Table 1.
NMR Spectroscopic Data (400 MHz, CD3OD), for Papuamides E (3) and F (4)
| Papuamide E (3) | Papuamide F (4) | |||
|---|---|---|---|---|
| δC | δHa | δC | δHa | |
| Homoproline (Hpr) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 52.7 | 5.32 m | 52.7 | 5.18 d (9.6) |
| 3 | 27.3 | 2.20 m, 1.77 m | 27.5 | 2.25 m |
| 4 | 21.1 | 1.26 m | 21.7 | 1.75 s |
| 5 | 26.9 | 1.76 m | 25.8 | 1.72 ovl |
| 6 | 44.3 | 4.15 m | 44.9 | 4.06 m |
| β-Methoxytyrosine (β-OMeTyr) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 54.0 | 5.15 d (5.2) | 54.0 | 5.22 m |
| 3 | 85.5 | 4.25 d (9.6) | 84.9 | 4.33 m |
| 3-OMe | 56.1 | 3.10 s | 56.9 | 3.15 s |
| 1′ | 129.3 | – | 129.1 | – |
| 2′, 6′ | 130.6 | 7.21 d (8.4) | 130.3 | 7.20 d (8.4) |
| 3′, 5′ | 116.0 | 6.77 d (8.4) | 116.0 | 6.76 d (8.4) |
| 4′ | 159.2 | – | 158.7 | |
| N-Methylthreonine (NMeThr/Thr-2) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 59.3 | 3.37 m | 60.1 | 3.93 m |
| 3 | 64.1 | 3.89 m | 66.8 | 3.94 m |
| 4 | 20.0 | 0.52 d (6.4) | 19.7 | 0.76 d (6.0) |
| N-Me | 31.1 | 3.15 s | ||
| Alanine (Ala) | ||||
| 1 | n.o. | – | 175.0 | – |
| 2 | 51.1 | 4.68 m | 51.1 | 4.32 m |
| 3 | 15.8 | 1.46 d (7.2) | 17.4 | 1.47 d (7.6) |
| Glycine (Gly-1) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 43.8 | 3.85 s | 43.9 | 4.13 m, 3.85 m |
| 3-Methoxyalanine (3-OMeAla) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 56.0 | 4.18 m | 56.0 | 4.35 m |
| 3 | 70.9 | 3.44 m, 3.46 m | 71.9 | 3.83 m, 3.66 m |
| 3-OMe | 59.5 | 3.44 s | 59.2 | 3.38 s |
| 3-Hydroxyleucine (3-OHLeu) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 54.0 | 4.75 m | 54.9 | 4.87 m |
| 3 | 77.4 | 5.40 m | 77.6 | 5.40 m |
| 4 | 29.6 | 2.04 m | 29.4 | 2.03 m |
| 5 | 17.6 | 0.92 m | 16.8 | 0.91 ovl |
| 5′ | 19.8 | 0.90 m | 19.6 | 0.90 ovl |
| 3,4 - Dimethylglutamine (3,4-DiMeGln) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 58.7 | 4.21 m | 58.5 | 4.32 m |
| 3 | 39.7 | 2.15 m | 38.0 | 2.20 m |
| 4 | 42.9 | 2.64 m | 42.4 | 2.59 m |
| 5 | 180.5 | – | n.o. | – |
| 3-Me | 13.6 | 0.95 ovl | 14.0 | 0.98 d (6.8) |
| 4-Me | 15.5 | 1.19 d (7.2) | 15.5 | 1.16 d (7.2) |
| Aminobutenoic acid (Aba) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | n.o. | – | n.o. | – |
| 3 | 132.0 | 6.55 m | 131.1 | 6.57 q (7.2) |
| 4 | 13.0 | 1.77 d (4.3) | 12.9 | 1.78 d (4.0) |
| Threonine (Thr-1) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 59.6 | 4.60 d (3.2) | 59.7 | 4.60 d (3.2) |
| 3 | 68.9 | 4.40 m | 68.9 | 4.40 dd (6.4, 3.6) |
| 4 | 19.8 | 1.24 d (6.4) | 19.8 | 1.24 d (6.4) |
| Glycine (Gly-2) | ||||
| 1 | n.o. | – | n.o. | – |
| 2 | 44.0 | 4.14 m | 45.0 | 3.39 m, 3.38 m |
| 2,3-Dihydroxy-2,6,8-trimethyl-4,6-decadienoic acid (Dhtda) | ||||
| 1 | 178.5 | – | 178.4 | – |
| 2 | 48.7 | 2.41 m | 48.7 | 2.42 m |
| 3 | 71.5 | 4.72 m | 71.3 | 4.69 t (9.6) |
| 4 | 129.8 | 5.29 ovl | 129.8 | 5.29 m |
| 5 | 137.9 | 6.09 m | 137.8 | 6.08 dd (11.6, 2.8) |
| 6 | 132.0 | – | 132.0 | – |
| 7 | 139.6 | 5.26 m | 139.7 | 5.26 m |
| 8 | 35.4 | 2.36 m | 35.4 | 2.37 m |
| 9 | 31.3 | 1.35 m, 1.30 m | 31.1 | 1.39 m, 1.29 m |
| 10 | 12.3 | 0.89 ovl | 12.3 | 0.88 ovl |
| 2-Me | 14.2 | 1.05 d (6.4) | 14.1 | 1.05 d (6.8) |
| 6-Me | 16.8 | 1.80 s | 16.8 | 1.80 s |
| 8-Me | 20.8 | 0.98 d (6.8) | 20.8 | 0.98 ovl |
Ovl: overlapped; n.o.: not observed.
a
Coupling constants are in parentheses and given in hertz. Although an HMBC was recorded, more assignments thus appear not possible.