The reaction of L-cysteine methyl ester (I) with farnesyl bromide (II) by means of ammonia in methanol gives the S-derivative (III), which is Boc protected as usual yielding the protected cysteine (IV). The reduction of (IV) with diisobutylaluminum hydride in toluene affords the cysteine aldehyde (V), which is reductocondensed with the tripeptide L-valine-L-isoleucine-L-methionine methyl ester (VI) by means of sodium cyanoborohydride in acidic methanol giving the peptide ester (VII). Finally, this compound is hydrolyzed with barium hydroxide in methanol/water.