Figure 2. Synthetic RvD3/AT-RvD3 stereoisomers.

These isomers were prepared in enantiomerically pure form via stereocontrolled total synthesis and were fully characterized by NMR spectroscopy. (A) Structures of the isomers of RvD3/AT-RvD3 and color-coded illustration depicting the origin of R or S stereochemistry of each chiral alcohol group from stereochemically pure precursors (Winkler et al., 2013). (B) Assignment of the Z or E stereochemistry for each C=C bond using 2-dimensional NMR spectroscopy. The shown ¹H-¹H gCOSY spectrum of a solution of RvD3 in CD₃OD [9.6x10⁻³M] was acquired using a Varian VNMRS 600 MHz NMR spectrometer at 25°C on a 5mm Triple Resonance PFG ¹H and referenced to the CD₃OD and an internal standard. This spectrum depicts all of the connectivities between adjacent alkenyl hydrogens (H₅-H₁₀, H₁₃-H₁₆, H₁₉-H₂₀). The colors denote a bitmap plotting method using a rainbow palette that gives depth to the positive and negative contours. The complete identification of each H-atom using this in combination with its corresponding constants (J values) permitted the unambiguous E/Z assignment of all alkenyl hydrogens (see Results).