Triethylamine → Amino-2-ethyl-4-hydroxy-7-methyloctanoic acid isobutylamide

Participants

Reaction Conditions

Reaction Steps

20.7 mg of L-N-[(2R or S)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucine was dissolved in 0.5 ml of dry DMF. Then, 17.4 μl of triethylamine, 12.9 μl of DPPA and 20 mg of (2RS,4S,5S)-5-amino-2-ethyl-4-hydroxy-7-methyloctanoic acid isobutylamide monohydrochloride was added thereto under stirring at -15° C. The mixture was stirred at the same temperature for one hour and then at 5° C. overnight. The reaction solution was diluted with 20 ml of ethyl acetate, washed with water and with a saturated sodium chloride aqueous solution and dried over anhydrous sodium sulfate. Then, the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (chloroform/methanol=50/1) to obtain 16.9 mg of (2RS,4S,5S)-5-{L-N-[(2R or S)-5-ethylthio-2-(1-naphthylmethyl)pentanoyl]norleucyl}amino-2-ethyl-4-hydroxy-7-methyloctanoic acid isobutylamide as colorless solid.

Provenance & Evidence