Hydrochloric Acid → Amino-2-hydroxy-5-methylhexyl benzyl ether

Participants

Reaction Steps

To a suspension of 31 mg of N-[(+)-2-(1-naphthylmethyl)-3-(phenethylcarbamoyl)propionyl]-L-histidine hydrazide in 1 ml of N,N-dimethylformamide were added successively dropwise 0.044 ml of a dry 5.1N-hydrogen chloride in N,N-dimethylformamide solution and 0.011 ml of isoamyl nitrite, and the mixture was stirred. After disappearance of hydrazide compound, the reaction mixture was cooled to +30° C., and neutrlized by adding 0.031 ml of triethylamine to prepare a solution of N-[(+)-2-(1-naphthylmethyl)-3-(phenethylcarbamoyl)-propionyl]-L-histidine azide. The azide solution prepared was added dropwise to a solution of 16 mg of (2RS, 3S)-3-amino-2-hydroxy-5-methylhexyl benzyl ether hydrochloride and 0.011 ml of triethylamine in 1 ml of N,N-dimethylformamide under ice-cooling, and the mixture was stirred for 16 hours under ice-cooling. A 5% aqueous sodium bicarbonate solution was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with a saturated sodium chloride aqueous solution, dried over anhydrous magnesium sulfate, and evaporated under reduced pressure. The residue was purified by preparative silica gel thin layer chromatograpy (developing solvent: lower layer of chloroform/methanol/water=8/3/1 by volume) to obtain 18 mg of (2RS, 3S)-3-{N-(+)-2-(1-naphthylmethyl)-3-(phenethylcarbamoyl)propionyl]-L-histidyl}amino-2-hydroxy-5-methylhexyl benzyl ether as a white powder.

Provenance & Evidence