FIGURE 7.

Partial ¹H-¹³C two-dimensional HSQC (green) and HMBC (orange) NMR spectra of β-S-thioether-linked compounds in D₂O, where ¹H chemical shifts are plotted on the x axis (2.60–4.65 ppm), ¹³C chemical shifts are plotted on the y axis (24.0–64.0 ppm), and non-¹H-¹³C-correlating HMBC spectral regions are indicated (gray). Proton assignment labels correspond with the carbon to which the proton is bound. Alphabetical subscripts differentiate two non-identical geminal protons. A, chemically synthesized GS-βVE. Proton peaks that did not integrate as expected are denoted with an asterisk (see “Results”). B, chemically synthesized mixture of GS-β(S)VG (red labels) and GS-β(R)VG (blue labels). Overlapping GS-β(S)VG and GS-β(R)VG ¹H and ¹³C spectral regions are indicated (black labels).