Table 1.
NMR spectroscopic data for compounds 1–4 in DMSO-d6.
| 1 | 2 | 3 | 4 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Position | δC a | δH b | HMBC | δC a | δH b | HMBC | δC a | δH b | HMBC | δC a | δH b | HMBC |
| 1 NH | 10.41 (1H, s) | 3 | 10.57 (1H, s) | 10.57 (1H, s) | 10.74 (1H, s) | |||||||
| 2 | 177.4, C | 176.9, C | 177.3, C | 177.2, C | ||||||||
| 3 | 78.1, C | 78.1, C | 77.8, C | 78.3, C | ||||||||
| 3-OH | 6.74 (1H, brs) | 6.91 (1H, brs) | 6.85 (1H, brs) | 7.00 (1H, s) | ||||||||
| 3a | 133.1, C | 135.4, C | 132.5, C | 135.2, C | ||||||||
| 4 | 124.1, CH | 6.99 (1H, d, 7.2) | 3, 6, 7a | 126.8, CH | 7.12 (1H, d, 2.0) | 3, 5, 6, 7, 7a | 126.0, CH | 6.95 (1H, d, 7.8) | 3, 6, 7a | 129.2, CH | 7.32 (1H, s) | 3, 3a, 5, 6, 7a |
| 5 | 121.6, CH | 6.89 (1H, dd, 7.5, 7.5) | 3a, 7 | 113.2, C | 124.2, CH | 7.08 (1H, dd, 8.1, 2.0) | 3a, 6, 7 | 115.8 C | ||||
| 6 | 129.4, CH | 7.20 (1H, dd, 7.5, 7.5) | 4, 7a | 132.0, CH | 7.39 (1H, dd, 8.2, 2.1) | 4, 5, 7a | 121.8, C | 124.6 C | ||||
| 7 | 109.8, CH | 6.84 (1H, d, 7.7) | 3a, 5 | 111.9, CH | 6.81(1H, d, 8.2) | 3, 3a, 4, 5, 7a | 112.6, CH | 6.99 (1H, d, 2.0) | 5, 6, 7a | 115.1, CH | 7.21 (1H, s) | 3a, 5, 6, 7a |
| 7a | 142.8, C | 142.2, C | 144.6, C | 144.0, C | ||||||||
| 1′ | - | - | - | - | - | - | - | - | - | |||
| 2′ | 162.9, C | 162.9, C | 162.9, C | 163.4, C | ||||||||
| 2′-NH2 | 6.48 (2H, brs) | 6.53 (2H, brs) | 6.51 (2H, brs) | 6.55 (2H, brs) | 2′, 4′, 6′ | |||||||
| 3′ | - | - | - | - | - | - | - | - | - | |||
| 4′ | 170.6, C | 170.0, C | 170.1, C | 169.9, C | ||||||||
| 5′ | 105.8, CH | 6.97 (1H, d, 5.1) | 3, 6′ | 105.8, C | 6.99 (1H, d, 5.1) | 3, 4′, 6′ | 105.7, CH | 6.97 (1H, d, 4.9) | 6′ | 106.3, CH | 7.00 (1H, d, 5.0) | 3, 4′, 6′ |
| 6′ | 158.9, CH | 8.28 (1H, d, 5.1) | 2′, 4′, 5′ | 159.1, C | 8.30 (1H, d, 5.1) | 3, 2′, 4′, 5′ | 159.0, CH | 8.30 (1H, d, 4.9) | 4′,5′ | 159.7, CH | 8.33 (1H, d, 5.0) | 3, 2′, 4′, 5′ |
a 125 MHz, multiplicity from HSQC; b 500 MHz (integration, multiplicity, J (Hz)).