Pyridine → (S)-2-[3-(6-Hydroxy-naphthalen-1-yl)-ureido]-pentanedioic acid 5-tert-butyl ester 1-methyl ester

Participants

Reaction Conditions

Reaction Steps

To H-Glu(OtBu)-OCH3 (2.0 mmol, 0.50 g) in dichloromethane (25 mL) at 0° C. was added pyridine (8 mmol, 0.66 mL) then followed by dropwise addition of phosgene in toluene (3.0 mmol, 1.60 mL, 1.92 M). After stirring at 0° C. for 2 hours, 1-amino-6-naphthol (2.0 mmol, 0.32 g) was added in dichloromethane. After stirring at room temperature for 12 hours, the reaction mixture was evaporated to dryness and purified on silica gel (1:19, methanol/dichloromethane) to provide product as a light brown solid (0.71 g, 88%).

Provenance & Evidence