Methyl alpha- and beta-pyranosides of d-glucose and d-galactose 1-4 were prepared containing single sites of (13)C-enrichment at C4, C5, and C6 (12 compounds), and (1)H and (13)C[(1)H] NMR spectra were obtained to determine a complete set of J-couplings ((1)J, (2)J, and (3)J) involving the labeled carbon and nearby protons and carbons within the exocyclic hydroxymethyl group (CH(2)OH) of each compound. In parallel theoretical studies, the dependencies of (1)J, (2)J, and (3)J involving (1)H and (13)C on the C5-C6 (omega) and C6-O6 (theta;) torsion angles in aldohexopyranoside model compounds were computed using density functional theory (DFT) and a special basis set designed to reliably recover the Fermi contact contribution to the coupling. Complete hypersurfaces for (1)J(C5,C6), (2)J(C5,H6)(R), (2)J(C5,H6)(S), (2)J(C6,H5), (2)J(C4,C6), (3)J(C4,H6)(R), (3)J(C4,H6)(S), and (3)J(C6,H4), as well as (2)J(H6)(R)(,H6)(S), (3)J(H5,H6)(R), and (3)J(H5,H6)(S), were obtained and used to parametrize new equations correlating these couplings to omega and/or theta;. DFT-computed couplings were also tested for accuracy by measuring J-couplings in (13)C-labeled 4,6-O-ethylidene derivatives of d-glucose and d-galactose in which values of omega and theta; were constrained. Using a new computer program, Chymesa, designed to utilize multiple J-couplings sensitive to exocyclic CH(2)OH conformation, the ensemble of experimental couplings observed in 1-4 were analyzed to yield preferred rotamer populations about omega and theta;. Importantly, due to the sensitivity of some couplings, most notably (2)J(H6)(R)(,H6)(S), (2)J(C5,H6)(R), and (2)J(C5,H6)(S), to both omega and theta;, unique information on correlated conformation about both torsion angles was obtained. The latter treatment represents a means of evaluating correlated conformation in 1,6-linked oligosaccharides, since psi and theta; are redundant in these linkages. In the latter regard, multiple, redundant scalar couplings originating from both sides of the glycosidic linkage can be used collectively to evaluate conformational correlations between psi/theta; and C5-C6 bond rotamers.

A new seven-parameter Karplus-type relation between vicinal proton-fluorine coupling constants and the corresponding H-C-C-F torsion angles has been developed. The optimum values of the seven parameters were determined using a data set consisting of 57 3 J HF values and the corresponding Φ HF torsion angles (ranging from cis, gauche, and trans regions) based upon ab initio structures as well as on the conformational analysis of temperature-dependent 3 J HH of monofluorinated nucleosides 1-11, which were also complemented with the data from conformationally fixed compounds 12-22. The best fit generalized Karplus-type equation shows the difference between input and back-calculated 3 J HF below 2.9 Hz with the overall rms deviation of 1.38 Hz, amounting to a total of 4% error for transoid coupling of ≈40-46 Hz, which compares very well with about 5% error encountered earlier in the experimental and the back-calculated 3 J HH of 8-9 Hz in the latest Karplus-Altona equation (ref 14). This is the first use of a new Karplus-type equation correlating 3 J HF with the H-C-C-F torsion angle in a quantitative manner (by making use of correction terms for substituent electronegativity as well as for H-C-C and F-C-C bond angles) to explore the pseudorotational equilibria of monofluorinated nucleosides 24 and 25 as well as difluorinated nucleosides 26-29 with the use of both 3 J HH and 3 J HF coupling constants in an iterative manner. The use of temperature-dependent 3 J HF in combination with 3 J HH greatly facilitates the conformational analysis of fluorinated sugar moieties of nucleosides because of the overwhelming increase of the number of experimental data points over the unknowns defining the pseudorotational equilibrium. This enables the pseudorotational parameters P and Ψ m of the two interconverting conformers to be more accurately defined. The best use of our new generalized Karplus-type relation is that it enables solution structure determination of fluorinated nucleosides or any other fluorinated compounds in which the number of measurable vicinal proton-proton couplings are not adequate enough to fully define the geometry of the system as in difluorinated nucleosides 26-29.

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Translation of the Bible or any other text unavoidably involves a determination about its meaning. There have been different views of meaning from ancient times up to the present, and a particularly Enlightenment and Modernist view is that the meaning of a text amounts to whatever the original author of the text intended it to be. This article analyzes the authorial-intent view of meaning in comparison with other models of literary and legal interpretation. Texts are anchors to interpretation but are subject to individualized interpretations. It is texts that are translated, not intentions. The challenge to the translator is to negotiate the meaning of a text and try to choose the most salient and appropriate interpretation as a basis for bringing the text to a new audience through translation.

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