Sodium Hydroxide → N-[(2,6-dichlorophenyl)carbonyl]-4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine

To a suspension of N-[(2,6-dichlorophenyl)carbonyl]-4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine methyl ester (2.2 mmol, 1.11 g) in ethanol (12 mL) was added aqueous 1.0 N sodium hydroxide (8.8 mL) at room temperature. The mixture was heated to 45-50° C. and the resulting clear solution was stirred for approximately 2 h. The ethanol was removed under reduced pressure and the residue was diluted with water (50 mL) and NaOH (5 mL, 1.0N) to dissolve the sodium salt. The aqueous solution was washed with diethyl ether (50 mL) to remove any neutral impurities. The aqueous layer was acidified with 1.0 N HCl and the product was extracted into ethyl acetate (2×75 mL). The combined organic extracts were washed with brine solution (100 mL) and were dried over anhydrous magnesium sulfate. Filtration of the drying agent and concentration of the filtrate afforded 970 mg (90% yield) of N-[(2,6-dichlorophenyl)carbonyl]-4-(1,3,6-trimethyl-2,4-dioxo-5-pyrimidinyl)-L-phenylalanine as a white solid: mp 225-227° C. FAB-HRMS m/e calcd for C23H21Cl2N3O5 (M+H) 490.0937, found 490.0940.

1. customThe ethanol was removed under reduced pressure
2. additionthe residue was diluted with water (50 mL) and NaOH (5 mL, 1.0N)
3. dissolutionto dissolve the sodium salt
4. washThe aqueous solution was washed with diethyl ether (50 mL)
5. customto remove any neutral impurities
6. extractionthe product was extracted into ethyl acetate (2×75 mL)
7. washThe combined organic extracts were washed with brine solution (100 mL)
8. dry with materialwere dried over anhydrous magnesium sulfate
9. filtrationFiltration of the drying agent and concentration of the filtrate

ORD record

ord-71889abe14264981ac43c85b5415cff9

Source dataset

uspto-grants-2002_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06380387B1