Synthesis of (2E,6E)-[10-3H]farnesol and (2E,6E)-[10-3H]farnesal for insect dehydrogenase studies

Article abstract of DOI:10.1002/jlcr.2580361106

[10-³H]Farnesol ((2E,6E)-3,7,11-trimethyl-2,6,10-dodecatrien-1-ol) and [10-³H]farnesal ((2E,6E)-3,7,11-trimethyl-2,6,10- -dodecatrian-1-al) were synthesized by sequential reduction and oxidation of the corresponding tert-butyldiphenylsilyl protected 11,12,13-trisnoraldehyde, followed by Wittig homologation using isopropyltriphenylphosphorane. Direct reduction of the C-12 allylic bromide or allylic chloride proved to be an nonviable method, resulting in either multiple decomposition products or significant double bond transposition. Oxidation of the [10-³H]labelled trisnoralcohol with pyridinium chlorochromate resulted in essentially complete retention of the radiolabel as was established for the corresponding deuterated material. [³H]labelled farnesol and farnesal were obtained in 78% and 74% yields, respectively, from the trisnoraldehyde. These materials were used as radiotracers for examining the enzymatic activity of insect farnesol and farnesal dehydrogenase, key enzymes in the biosynthesis of juvenile hormone.