Starting from D-mannitol, the total syntheses of methyl 9(S)- and 9(R)-hydroxy 5(Z), 7(E), 11(Z) eicosatetraenoate are described by two different ways. One route uses a diepoxide opening by an acetylide while the second one involved the transformation of a diepoxide into an equivalent of malic aldehyde, an important intermediate in the synthesis of other oxidation products of arachidonic acid. Both methods