TABLE 2.
1H NMR data for the peracetylated derivative of F. meningosepticum de-O-acylated lipid A-HCl containing a hybrid backbonea
| Unit | Value for chemical shift (coupling constant)b
|
||||||||
|---|---|---|---|---|---|---|---|---|---|
| H-1 | H-2 | H-3 | H-4 | H-5 | H-6a | H-6b | 2-NH | 3-NH | |
| Reducing terminal unit | |||||||||
| α-d-Glucosamine | 6.10 (3.3) | 4.41 (10.8) | 5.25 (9.4) | 5.15 (9.9) | 3.91 (2.2) | 3.41 (11.7) | 4.00 (4.8) | 6.04 (8.8) | |
| β-d-Glucosamine | 5.68 (8.8) | 4.29 (10.8) | 5.20 (9.2) | 4.91 (9.7) | 3.79 (2.3) | 3.68 (12.5) | 3.80 (NDc) | 6.34 (9.2) | |
| Nonreducing terminal unit, 2,3-di-amino-glucose | 4.38 (8.4) | 3.96 (10.4) | 4.09 (9.9) | 4.83 (9.9) | 3.70 (2.2) | 4.05 (12.6) | 4.24 (3.1) | 6.48 (7.7) | 6.37 (8.4) |
a
Spectra were recorded at 600 MHz in CDCl3 relative to TMS (0.00 ppm). Assignments were made by 1H,1H-COSY NMR. The α-, β-, γ-, methylene, and methyl protons of fatty acid residues were detected at 2.15 to 2.60, 4.94 to 5.24, 1.50 to 1.70, 1.15 to 1.35, and 0.85 to 0.90 ppm, respectively, and methyl protons of acetyl groups were detected at 2.00 to 2.25 ppm.
b
Chemical shift is expressed in parts per million; coupling constant (J) is expressed in hertz.
c
ND, not defined.