Synthesis and shift-reagent-assisted full NMR assignment of bacterial (Z8, E2, ω)-undecaprenol

The repeating isoprene unit is a fundamental biosynthetic motif. The repetitive structure presents challenges both for synthesis and for structural characterization. In this synthesis of the (Z(8), E-2, omega)undecaprenol of prokaryotic glycobiology, we exemplify solutions to these challenges. Allylation of sulfone-derived carbanions controlled the stereochemistry, and its proof-of-structure was secured by Eu(hfc)(3) complexation to disperse the overlaid resonances of its H-1 NMR spectrum.