Tetrahydrofuran → HCID 54110952, compound

Temperature

0 °C

A mixture of N-benzyloxycarbonyl-(L)-isoleucyl-(L)-tryptophan methyl ester (11.3 g), palladium-carbon (5%, 50% wet, 3.0 g) and THF (50 ml) was subjected to catalytic hydrogenation at room temperature and atmospheric pressure. After the catalyst was filtered off, the filtrate was concentrated under reduced pressure to yield an oily substance. The oil was dissolved in N,N-dimethylformamide (50 ml), and 1-naphthalenesulfonyl chloride (5.8 g) and 4-(N,N-dimethylamino)pyridine (DMAP) (3.2 g) were added to the ice-cooling mixture. After stirring at 0° C. for 3 hours, the reaction mixture was concentrated under reduced pressure. The residue was suspended in ethyl acetate and the mixture was successively washed with 10% aqueous citric acid solution, water, saturated aqueous sodium hydrogen carbonate and brine, and dried (MgSO4). The organic solvent was evaporated off to yield N-(1-naphthylsulfonyl)-(L)-isoleucyl-(L)-tryptophan methyl ester (9.8 g, 77%) as crystals. Melting point: 172°-174° C.

1. customwas subjected to catalytic hydrogenation at room temperature
2. filtrationAfter the catalyst was filtered off
3. concentrationthe filtrate was concentrated under reduced pressure
4. customto yield an oily substance
5. temperaturecooling mixture
6. concentrationthe reaction mixture was concentrated under reduced pressure
7. washthe mixture was successively washed with 10% aqueous citric acid solution, water, saturated aqueous sodium hydrogen carbonate and brine
8. dry with materialdried (MgSO4)
9. customThe organic solvent was evaporated off

ORD record

ord-83365a1161e74110bdbc4163de2f18af

Source dataset

uspto-grants-1997_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05639781