D-Phenylalanine → HCID 68297757, compound

Participants

Reaction Steps

A mixture of 1-benzyl-5-hydroxy-2-oxo-3-phenyl-1,2-dihydro-[1,7]naphthyridine-6-carboxylic acid methyl ester (60 mg, 0.16 mmol), D-phenylalanine (514 mg, 3.1 mmol), and NaOMe (126 mg, 2.3 mmol) in 2-methoxyethanol (10 mL) was refluxed for 2 h. After the mixture was cooled to r.t., solvent was evaporated in vacuo. The residue was partitioned between EtOAc and water. 1 M HCl was added with vigorous stirring until pH was about 3. The organic layer was dried over MgSO4 and concentrated. The residue was purified by silica gel chromatography (0-60% EtOAc/hexanes+1% AcOH). The product isolated was dissolved in saturated NaHCO3 and washed several times with ether. The aqueous layer was acidified to pH about 3 with 6 M HCl, and the resulting precipitate was isolated by filtration to give 36 mg of the title compound as a dull yellow solid. MS: (+) m/z 520.27 (M+1).

Provenance & Evidence