Synthesis of [13C3]-B6 Vitamers Labelled at Three Consecutive Positions Starting from [13C3]-Propionic Acid

Abstract

[13C3]-labelled vitamers (PN, PL and PM) of the B6 group were prepared starting from [13C3]-propionic acid. [13C3]-PN was synthesized in ten linear steps with an overall yield of 17%. Hereby, higher alkyl homologues of involved esters showed a positive impact on the reaction outcome of the intermediates in the chosen synthetic route. Oxidation of [13C3]-PN to [13C3]-PL was undertaken using potassium permanganate and methylamine followed by acid hydrolysis of the imine derivative. [13C3]-PM could be prepared from the oxime derivative of [13C3]-PN by hydrogenation with palladium.

Keywords

• labelled vitamers
• pyridoxine
• pyridoxal
• pyridoxamine
• vitamin B6
• synthesis
• isotopologues