合成路线1

Alternatively, 8-bromo-1-octene (IX) is converted into the corresponding Grignard reagent (X) which is further carboxylated by solid carbon dioxide in cold THF to produce acid (XI). Coupling of acid (XI) with the lithium derivative of (S)-4-benzyl-2-oxazolidinone (XII), via activation with pivalic anhydride, leads to the chiral N-acyl oxazolidinone (XIII). Stereoselective alpha-azidation of the potassium enolate of (XIII) with trizylazide forms the (S)-azide (XIV). Subsequent reduction of azide (XIV) employing SnCl2 leads to amine (XV), which is further protected as the N-Boc derivative (XVI) with Boc2O in the presence of NaHCO3. Then, hydrolysis of the chiral auxiliary of (XVI) by means of lithium hydroperoxide gives rise to the desired N-Boc aminoacid (VIII).