Reaction #1909790

Reaction equation

3,5-dihydroxy-2-naphthoic acid

L-phenylalanine methyl ester hydrochloride

WSC.HCl

HOBT

N-methylmorpholine

→

title compound

Yield 61.0%

(2S)-3-Phenyl-2-(3,5-dihydroxy-2-naphthoylamino)propionic acid methyl ester

Yield 61.0%

Solvents

Water

DMF

Conditions

Workup

1. 1
   Extractionthe mixture was extracted with ethyl acetate
2. 2
   WashThe organic layer was washed successively with a 10% aqueous citric acid solution, water
3. 3
   Dryinga saturated aqueous sodium hydrogencarbonate solution, water and saturated brine, dried over anhydrous sodium sulfate
4. 4
   Concentrationconcentrated under reduced pressure
5. 5
   OtherThe residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate-1/1 v/v)

Procedure

A solution of 3,5-dihydroxy-2-naphthoic acid (4.08 g), L-phenylalanine methyl ester hydrochloride (4.74 g), WSC.HCl (4.22 g), HOBT (2.97 g) and N-methylmorpholine (2.41 ml) in DMF (200 ml) was stirred at room temperature for 16 hours. Water was added to the reaction mixture, and the mixture was extracted with ethyl acetate. The organic layer was washed successively with a 10% aqueous citric acid solution, water, a saturated aqueous sodium hydrogencarbonate solution, water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (developing solvent: hexane/ethyl acetate-1/1 v/v) to give the title compound (4.42 g, yield 61%).

Source