Synthesis of enantiopure ABC-type triacylglycerols

Abstract

The synthesis of twelve enantiopure structured triacylglycerols (TAGs) of the ABC type possessing three different fatty acids is described by a six-step chemoenzymatic approach starting from (S)-solketal. Eight of the TAGs possess two different saturated fatty acyl groups located in the sn-1 and sn-2 positions with an unsaturated fatty acyl group in the remaining sn-3 position of the glycerol skeleton, whereas the remaining four possess two different saturated acyl groups in the terminal sn-1 and sn-3 positions with an unsaturated acyl group in the sn-2 position. The former group was synthesised by a six-step chemoenzymatic route involving a highly regioselective immobilised Candida antarctica lipase. The second group was prepared by a similar six-step approach, that required two separate lipase steps. Such enantiopure TAGs are strongly demanded as standards for enantiospecific analysis of intact TAGs in fats and oils.