The first synthesis of threo and erythro (E)-4, 5-dihydroxydec-2-enals, aldehydes related to the lipid peroxidation is accomplished by reaction of α-benzoyloxheptanal with the Grignard reagent of 3, 3-diethoxy-1-propyne and lithium aluminum hydride reduction. Acetonization of the diol system allows a simple chromatographic separation of the diastereoisomers, the geometry of which was established by 1H and 13C NMR experiments and was confirmed ...