反应详情

A mixture of fmoc-D-Nle-OH (10 g, 28.3 mmol, Novabiochem) and PS-carbodiimide (33 g, 42.45 mmol, 1.28 mmol/g, Argonaut Technologies Inc.) in dichloromethane (250 mL) was stirred at room temperature for 0.5 h. Then, glycine methyl ester hydrochloride (5.3 g, 42.45 mmol, Aldrich), HOAt (3.8 g, 28.3 mmol, Perseptive Biosystems) and diisopropylethylamine (16 mL, 84.9 mmol, Aldrich) were added and the mixture was stirred at room temperature for 16 h. The mixture was filtered and the resin was washed with dichloromethane (2×70 mL). The filtrate was concentrated in vacuo and the residue was purified by column chromatography, eluting with EtOAc/hexane (1:2) to give the title compound as a yellow solid. MS (ESI, positive ion) m/z: 425 (M+1).

1. stirringthe mixture was stirred at room temperature for 16 h
2. filtrationThe mixture was filtered
3. washthe resin was washed with dichloromethane (2×70 mL)
4. concentrationThe filtrate was concentrated in vacuo
5. customthe residue was purified by column chromatography
6. washeluting with EtOAc/hexane (1:2)