Stereocontrolled synthesis of the PPAR-gamma agonist 10-nitrolinoleic acid

The naturally occurring PPAR-gamma ligand 10-nitrooctadeca-9(E),12(Z)-dienoic acid (10-nitrolinoleic acid) (2a) was prepared as a single regio- and geometrical isomer in a practical eight-step, convergent sequence. The synthetic route featured a nitro aldol reaction between 9-oxononanoic acid methyl ester (3) and 1-nitronon-3(Z)-ene (4) in the key carbon-carbon bond forming step. The ability of 2a (and its methyl ester 9) to bind to PPAR-gamma in a ligand-binding assay is reported.