Synthesis of the lipid peroxidation product 4-hydroxy-2(E)-nonenal with 13C stable isotope incorporation

The aim of this work was to synthesize C-13 internal standards for the quantification of 4-hydroxy-2(E)-nonenal(HNE), a lipid peroxidation product, and of the etheno-adducts possibly formed by HNE damage to DNA nucleobases. We designed an eight-step synthesis starting from ethyl 2-bromoacetate and giving access to 4-[(tetrahydro-2H-pyran-2-yl)oxrl-2(E)nonenal. This compound is a precursor of HNE. The scheme was then used to produce the 13C precursor [1,2- C-13(2)]-4-[(tetrahydro-2H-pyran-2-yl)oxyl-2(E)-nonenal. [1,2- C-13(2)]-HNE was obtained by acid cleprotection. All the intermediary and final compounds were fully characterized by IR, HRMS, H-1 and C-13 NMR. it is the first synthesis of HNE which enables the incorporation Of two C-13 labels at determined positions.