The values of Bock and Duus [1] are based on the Karplus equation of Haasnoot et al. [2] whereas those of Stenutz et al. [3] are based on quantum mechanical calculations in 2-hydroxymethyl tetrahydropyran (oxane). Apart from slight differences in the relationship between torsion angles and coupling constants Stenutz et al. assume a larger torsion (65°) for the gg and gt rotamers.
The θ torsion is defined here as C5-C6-O6-X, i.e. H or glycosyl/alkyl. The amount of trans can be estimated from 2JH6R,H6S if the amounts of the ω rotamers are known.
The ω rotamers are estimated to be accurate to about +-5%, but the error in
θ is larger since 1) the relationship between 2JH6R,H6S
is less reliable and 2) the ω rotamer populations are required. An error of at
least +-10% is to be expected.
[1] K. Bock and J.Ø. Duus,
J. Carbohydr. Chem. 13 (1994) 513-543
[2] C.A.G. Haasnoot, F.A.A.M. DeLeeuw and C. Altona, Tetrahedron 36 (1980) 2783-2792.
[3] R. Stenutz, I. Carmichael, G. Widmalm and A.S. Serianni, J. Org. Chem. 67 (2002) 949-958 DOI 10.1021/jo010985i
| Coupling constants | Bock & Duus | Stenutz et al. | ||||||||
| Compound | 3JH5,H6R | 3JH5,H6S | 2JH6R,H6S | Pgt | Pgg | Ptg | Pgt | Pgg | Ptg | θtrans |
| methyl α-D-glucopyranoside | 5.49 | 2.39 | -12.35 | 50 | 57 | -7 | 47 | 42 | 10 | 7 |
| methyl α-D-glucopyranoside (CD3OD) | 5.64 | 2.40 | -11.80 | 51 | 56 | -7 | 49 | 41 | 11 | 26 |
| methyl β-D-glucopyranoside | 6.11 | 2.47 | -12.31 | 56 | 50 | -6 | 54 | 35 | 11 | 9 |
| α-D-glucopyranose (DMSO) | 5.00 | 2.30 | -11.20 | 45 | 63 | -8 | 42 | 48 | 10 | 46 |
| β-D-glucopyranose | 5.78 | 2.29 | -12.33 | 53 | 55 | -8 | 51 | 40 | 9 | 9 |
| β-D-glucopyranose (DMSO) | 5.90 | 2.20 | -11.80 | 55 | 55 | -10 | 53 | 39 | 8 | 27 |
| methyl α-D-mannopyranoside | 6.40 | 2.44 | -12.20 | 59 | 48 | -7 | 57 | 32 | 11 | 12 |
| methyl 2-acetamido-2-deoxy-β-D-glucopyranoside | 5.38 | 2.35 | -12.20 | 49 | 59 | -8 | 46 | 44 | 10 | 13 |
| 6-O-methyl-α-D-glucopyranose | 5.73 | 2.37 | -11.04 | 52 | 55 | -7 | 50 | 40 | 10 | 51 |
| 6-O-methyl-β-D-glucopyranose | 6.10 | 2.16 | -11.20 | 57 | 53 | -10 | 55 | 37 | 8 | 47 |
| 4,6-di-O-methyl-β-D-glucopyranose | 5.64 | 1.96 | -11.14 | 54 | 59 | -13 | 51 | 43 | 6 | 50 |
| methyl 6-O-acetyl-β-D-glucopyranoside | 4.90 | 2.30 | -12.30 | 44 | 64 | -8 | 41 | 49 | 10 | 9 |
| methyl 4,6-di-O-acetyl-β-D-glucopyranoside | 3.80 | 2.10 | -12.60 | 34 | 76 | -10 | 30 | 62 | 8 | 0 |
| methyl 6-O-phosphono-α-D-glucopyranoside (pH 1.3) | 4.60 | 2.40 | -11.60 | 41 | 66 | -7 | 37 | 52 | 11 | 32 |
| methyl 6-O-phosphonato-α-D-glucopyranoside (pH 9.3) | 3.53 | 1.91 | -12.13 | 32 | 80 | -12 | 28 | 67 | 6 | 17 |
| methyl 4-deoxy-α-D-xylo-hexopyranoside | 6.20 | 3.03 | -12.06 | 54 | 45 | 1 | 52 | 31 | 17 | 14 |
| methyl 4-deoxy-β-D-xylo-hexopyranoside | 7.42 | 3.34 | -12.04 | 65 | 31 | 4 | 65 | 15 | 20 | 14 |
| methyl 4-O-acetyl-β-D-glucopyranoside | 5.90 | 2.20 | -12.30 | 55 | 55 | -10 | 53 | 39 | 8 | 10 |
| methyl 4,4-di-hydroxy-α-D-xylo-hexopyranoside | 8.40 | 2.40 | -12.00 | 80 | 28 | -8 | 79 | 11 | 10 | 19 |
| methyl 4-thio-α-D-glucopyranoside | 5.00 | 2.00 | -12.50 | 47 | 65 | -12 | 44 | 50 | 6 | 4 |
| methyl 4-ammonio-4-deoxy-α-D-glucopyranoside (pH 2.0) | 4.64 | 3.70 | -12.44 | 34 | 56 | 10 | 32 | 43 | 25 | -1 |
| methyl 4-amino-4-deoxy-α-D-glucopyranoside (pH 9.0) | 5.40 | 2.46 | -12.42 | 48 | 58 | -6 | 46 | 43 | 11 | 5 |
| C-propyl β-D-glucopyranoside | 8.50 | 2.40 | 81 | 27 | -8 | 81 | 10 | 10 | ||
| methyl α-D-galactopyranoside | 8.60 | 3.70 | -11.70 | 75 | 16 | 9 | 76 | 0 | 24 | 24 |
| methyl β-D-galactopyranoside | 7.50 | 4.83 | -11.76 | 58 | 19 | 24 | 59 | 5 | 36 | 17 |
| β-D-galactopyranose | 7.92 | 4.28 | -11.50 | 65 | 19 | 16 | 66 | 4 | 30 | 28 |
