反应详情

To (S)-3-[(2S,3R,4R,5S)-2,3,4,6-tetrahydroxy-5-(L-leucyl)aminohexanoyl]amino-3-phenylpropionic acid (Compound 3) (500 mg) was added a 28% solution of hydrogen chloride in ethanol (200 ml) and the mixture was stirred at room temperature for 20 hours. After concentration, the residue was subjected to silica gel column chromatography and eluted with acetonitrile-water (5:1). The effective fractions were combined and concentrated under reduced pressure. The residue was dissolved in water (10 ml) and neutralized with aqueous sodium hydrogencarbonate solution. The solution was passed through a column of DIAION HP-20SS (Mitsubishi kasei corporation), followed by elution with water-acetonitrile. The effective fractions were combined and concentrated under reduced pressure. The residue was recrystallized from chloroform-diethylether to afford the title compound (123 mg).

1. concentrationAfter concentration
2. washeluted with acetonitrile-water (5:1)
3. concentrationconcentrated under reduced pressure
4. dissolutionThe residue was dissolved in water (10 ml)
5. washfollowed by elution with water-acetonitrile
6. concentrationconcentrated under reduced pressure
7. customThe residue was recrystallized from chloroform-diethylether