HCID 15617231, compound → HCID 53822611, compound

A solution of (S)-N-(3-nitro-2-pyridinyl)alanine ethyl ester (5.0 g, 0.0209 mole) in tetrahydrofuran (60 ml) was hydrogenated over 5% palladium on carbon (0.5 g) keeping the temperature of the solution at approximately room temperature to give (S)-N-(3-amino-2-pyridinyl) alanine ethyl ester. The solution of the reduction product was cooled in an ice bath and dried over magnesium sulfate under nitrogen. The solution was filtered and 4-chlorobenzoyl chloride (3.84 g, 0.022 mole) and triethylamine (2.22 g, 0.022 mole) were added simultaneously, dropwise, to the cooled and stirred solution. The reaction mixture was stirred at room temperature overnight under nitrogen and the solvents were removed under reduced pressure. The residue was partitioned between water (50 ml) and ethyl acetate (50 ml). The layers were separated and the aqueous layer was extracted again with ethyl acetate. The combined organic layers were washed twice with water, dried over magnesium sulfate, treated with charcoal, filtered and evaporated to an oil weighing 6.2 g (85% yield). A 2.2-g portion of the oil was dissolved in isopropyl alcohol and the solution was acidified with ethereal hydrogen chloride. The resulting solid was filtered and dried under high vacuum to give 1.70 g of title compound, mp 172°-177° C. with decomposition.

1. customat approximately room temperature

ORD record

ord-b30b0213f4f64769a7fbd551ca1577ef

Source dataset

uspto-grants-1989_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04873251