FIGURE 6.

Aligned ¹H NMR partial spectra (2.60–4.65 ppm) of the GS conjugate, GS-βVE, in D₂O. Proton assignment labels correspond with the carbon to which the proton is bound. Alphabetical subscripts differentiate two non-identical geminal protons. Proton peaks that did not integrate as expected are denoted with an asterisk (see “Results”). A, compound GS-βVE obtained via chemical synthesis. B–D, reaction product GS-βVE isolated from LigE (B), LigP (C), or LigF (D) activities using the achiral model compound GβVE as a substrate.