Table 1.
NMR Spectroscopic Data (500 MHz, CDCl3) of compound 3 (betulinic acid-3-trans-caffeate)
| Position | Compound 3 | |
|---|---|---|
| δH (J in Hz) | δC, type | |
| 1 | 1.73 (m), 1.07 (m) | 39.2, CH2 |
| 2 | 1.68 (m), 1.68 (m) | 24.6, CH2 |
| 3 | 4.57 (t, 5.1) | 81.2, CH |
| 4 | – | 38.3, C |
| 5 | 0.91 (m) | 55.7, CH |
| 6 | 1.53 (m), 1.46 (m) | 19, CH2 |
| 7 | 1.39 (m), 1.51 (m) | 35.1, CH2 |
| 8 | – | 42.7, C |
| 9 | 1.43 (m) | 50.7, CH |
| 10 | – | 34.6, C |
| 11 | 1.12 (m), 1.46 (m) | 21.8, CH2 |
| 12 | 1.26 (m), 1.74 (m) | 26.4, CH2 |
| 13 | 2.39 (m) | 39.0, CH |
| 14 | – | 43.3, C |
| 15 | 1.59 (m), 1.20 (m) | 30.5, CH2 |
| 16 | 2.26 (m) 1.44 (m) | 32.9, CH2 |
| 17 | – | 56.8, C |
| 18 | 1.59(m) | 49.5, CH |
| 19 | 3.0(m) | 47.1, CH |
| 20 | – | 150, C |
| 21 | 1.93 (m), 1.37 (m) | 31.4, CH2 |
| 22 | 1.50 (m), 1.92 (m) | 37.9, CH2 |
| 23 | 0.86 (s) | 28.3, CH3 |
| 24 | 0.89 (s) | 16.3, CH3 |
| 25 | 0.93 (s) | 16.9, CH3 |
| 26 | 0.97 (s) | 16.4, CH3 |
| 27 | 0.97 (s) | 14.9, CH3 |
| 28 | – | 177.8, C |
| 29 | 4.60, 4.57 (brs) | 110, CH2 |
| 30 | 1.68 (s) | 19.6, CH3 |
| 1′ | – | 128, C |
| 2′ | 7.07 (d, 1.2) | 122.6, CH |
| 3′ | – | 115.8, C |
| 4′ | – | 146.1, C |
| 5′ | 6.86 (d, 8.0) | 143.9, CH |
| 6′ | 6.99 (dd, 8.0, 1.2) | 114.6, CH |
| 7′ | 7.53 (d, 15.9) | 144.3, CH |
| 8′ | 6.24 (d, 15.9) | 116.9, CH |
| 9′ | – | 167.7, C |
Assignments were based on 2D NMR including HSQC, HMBC and NOESY. Well-resolved couplings are expressed with coupling patterns and coupling constants in hertz in parentheses