Table 2.
Comparison of structural information obtained from thiolysis and 1H-13C HSQC NMR.
| Plant Sample | PC/PD Ratio | cis/trans | % Galloyl | mDP | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Thiol | NMR | Thiol | NMR H/C-4 | NMR H/C-2 | Thiol | NMR H/C-4 | NMR H/C-2′,5′ | Thiol | NMR | |
| Desmodium paniculatum | 55/45 | 52.5/47.5 | 90/10 | 87.8/12.2 | 84.2/15.8 | None | None | None | 18.6 | ND 1 |
| Lespedeza stuevei | 42/58 | 41.4/58.6 | 44/56 | 34.8/65.2 | 33.9/66.1 | 3 | 2.4 | 1.0 | 9.3 | 6.7 |
| Lespedeza cuneata | 8/92 | 4.3/95.7 | 80/20 | 82.1/17.9 | 75.4/24.6 | None | ND 2 | 5.3 | 10.6 | 9.1 |
| Mimosa strigillosa | 15/85 | 15.3/84.7 | 89/11 | ND 3 | ND 4 | 40 | 50.8 | ND 5 | 7.6 | 6.1 |
| Desmanthus illinoensis | 3/97 | 1.8/98.2 | 98/2 | ND 3 | 96.2/3.8 | 75 | 76.2 | 87.5 | 6.0 | 5.97 |
| Neptunia lutea | 12/88 | 8.2/91.8 | 93/7 | ND 3 | 91.5/8.5 | 32 | 34.4 | 25.6 | 11.5 | 8.1 |
| Leucaena retusa | 99/1 | 98.6/1.4 | 98/2 | ND 3 | ND 4 | 29 | 21.3 | 34.3 | 39.2 | 6.3 |
ND, not determined. 1 Low signal to noise ratio on terminal C-H cross-peak signal. 2 Low signal to noise ratio for H/C-4 cross-peak signal. 3 Due to galloylation of the CT sample, cis/trans assignments become ambiguous using H/C-4 cross-peaks. 4 Low signal to noise ratio for the trans H/C-2 cross-peak signal. 5 Integration of peaks indicated > 100 mol % galloylation.