Table 1.
NMR spectral data of compound DGQ in methanol-d4 and water-d2 and compound DGK in methanol-d4 (600 MHz for 1H and 150.9 MHz for 13C) a.
| DGQ | DGK | ||||||
|---|---|---|---|---|---|---|---|
| Pos. b | δH c | δC c | δH d | δC d | Pos. b | δH c | δC c |
| 2 | 157.3 | 156.8 | 2 | 157.2 | |||
| 3 | 133.8 | 133.5 | 3 | 133.5 | |||
| 4 | 178.1 | 177.4 | 4 | 178.1 | |||
| 5 | 161.5 | 159.7 | 5 | 161.7 | |||
| 6 | 6.17 (1H, d, J = 1.9) | 98.5 | 5.89 (1H, d, J = 1.7) | 98.7 | 6 | 6.21 (1H, d, J = 1.9) | 98.4 |
| 7 | 164.4 | 162.6 | 7 | 164.4 | |||
| 8 | 6.36 (1H, d, J = 1.9) | 93.3 | 5.95 (1H, d, J = 1.7) | 94.3 | 8 | 6.41 (1H, d, J = 1.9) | 93.3 |
| 9 | 156.9 | 155.9 | 9 | 157.2 | |||
| 10 | 104.4 | 104.3 | 10 | 104.5 | |||
| 1′ | 121.7 | 121.5 | 1′ | 121.4 | |||
| 2′ | 7.66 (1H, d, J = 1.9) | 116.2 | 7.27 (1H, d, J = 1.7) | 116.4 | 2′, 6′ | 8.08 (2H, d, J = 9.0) | 130.9 |
| 3′ | 144.6 | 143.4 | 3′, 5′ | 6.91 (2H, d, J = 9.0) | 114.8 | ||
| 4′ | 148.4 | 147.3 | 4′ | 160.1 | |||
| 5′ | 6.88 (1H, d, J = 8.3) | 114.8 | 6.65 (1H, d, J = 8.9) | 115.3 | |||
| 6′ | 7.59 (1H, dd, J1 = 1.9, J2 = 8.3) | 122.1 | 7.15 (1H, dd, J1 = 1.7, J2 = 8.9) | 122.6 | |||
| 3-β-d-glucuronopyranosyl: | |||||||
| 1″ | 5.54 (1H, d, J = 7.5) | 99.8 | 5.29 (1H, d, J = 7.5) | 99.5 | 1″ | 5.58 (1H, d, J = 7.2) | 99.6 |
| 2″ | 3.80 (1H, dd, J = 7.5, J2 = 9.0) | 80.1 | 3.82 (1H, dd, J = 7.5, J2 = 8.3) | 79.4 | 2″ | 3.74 (1H, dd, J = 7.2, J2 = 9.4) | 80.5 |
| 3″ | 3.66 (1H, dd, J1 = 9.0, J2 = 9.8) | 71.6 | 3.64 (1H, dd, J1 = 8.3, J2 = 9.0) | 71.5 | 3″ | 3.63 (1H, dd, J1 = 9.4, J2 = 9.8) | 71.5 |
| 4″ | 3.68 (1H, dd, J1 = 9.8, J2 = 10.2) | 76.7 | 3.70 (1H, dd, J1 = 9.0, J2 = 9.4) | 76.4 | 4″ | 3.67 (1H, dd, J1 = 9.8, J2 = 10.2) | 76.4 |
| 5″ | 3.74 (1H, d, J = 10.2) | 75.4 | 3.80 (1H, d, J = 9.4) | 76.0 | 5″ | 3.71 (1H, d, J = 10.2) | 75.6 |
| 6″ | 173.4 | 174.5 | 6″ | 173.7 | |||
| 2″-β-d-xylopyranosyl: | |||||||
| 1‴ | 4.77 (1H, d, J = 7.5) | 103.8 | 4.76 (1H, d, J = 7.5) | 103.1 | 1‴ | 4.78 (1H, d, J = 6.8) | 103.9 |
| 2‴ | 3.29 (1H, dd, J1 = 7.5, J2 = 9.8) | 73.5 | 3.26 (1H, dd, J1 = 7.5, J2 = 9.0) | 73.3 | 2‴ | 3.37 (1H, dd, J1 = 6.8, J2 = 8.3) | 73.5 |
| 3‴ | 3.36 (1H, dd, J1 = 9.8, J2 = 9.8) | 75.7 | 3.43 (1H, dd, J1 = 9.0, J2 = 9.0) | 75.5 | 3‴ | 3.40 (1H, dd, J1 = 8.3, J2 = 8.7) | 75.6 |
| 4‴ | 3.48 (1H, ddd, J1 = 5.3, J2 = 9.8, J3 = 10.2) | 69.6 | 3.54 (1H, ddd, J1 = 5.7, J2 = 9.0, J3 = 9.6) | 69.3 | 4‴ | 3.53 (1H, ddd, J1 = 4.9, J2 = 8.3, J3 = 8.7) | 69.6 |
| 5‴ | 3.17 (1H, dd, J1 = 10.2, J2 = 11.7, H-5a‴) | 65.2 | 3.19 (1H, dd, J1 = 9.6, J2 = 10.5, H-5a‴) | 65.1 | 5‴ | 3.23 (1H, dd, J1 = 8.7, J2 = 11.3, H-5a‴) | 65.2 |
| 3.84 (1H, dd, J1 = 5.3, J2 = 11.7, H-5e‴) | 3.83 (1H, dd, J1 = 5.7, J2 = 10.5, H-5e‴) | 3.94 (1H, dd, J1 = 4.9, J2 = 11.3, H-5e‴) | |||||
a Data acquired with TMS as the internal standard, δ in ppm. Multiplicities and coupling constants (in Hz) are given in parentheses. Assignments confirmed by 1H-1H COSY, HMQC, and HMBC experiments. b For trivial atom numbering, see the chemical formula of DGQ (wintergreenoside A) and DGK (wintergreenoside B) (Figure 3). c Data acquired in methanol-d4. d Data acquired in water-d2.