反应详情

温度

80 °C

Benzoyl isothiocyanate (1.3 mL, 9.8 mmol) was added to tert-butyl {2-[(5-carbamoyl-1H-imidazol-4-yl)amino]ethyl}carbamate (2.5 g, 9.3 mmol, obtained from Example 26(a)) in dichloromethane (25 mL) and methanol (0.050 mL) at 0° C. The mixture was allowed to reach r.t. and stirred for 3 h. After removal of solvents, the residue was dissolved in ammonia (7 N in methanol, 30 mL) and subjected to microwave heating at 80° C. for 5 h. The solvent was then evaporated and the Boc-protected product was purified by silica gel column chromatography (dichloromethane/methanol 95:5) which gave 1.5 g (52% yield). This material (1.5 g, 4.9 mmol) was dissolved in dichloromethane (50 mL) and treated with trifluoroacetic acid (7 mL). After 2 h, the mixture was concentrated, diethyl ether was added and the solid was collected and dried in vacuo to afford 1.1 g (67% yield) of the title compound as its trifluoroacetic acid salt.

1. customto reach r.t.
2. customAfter removal of solvents
3. dissolutionthe residue was dissolved in ammonia (7 N in methanol, 30 mL)
4. customThe solvent was then evaporated
5. customwas purified by silica gel column chromatography (dichloromethane/methanol 95:5) which
6. customgave 1.5 g (52% yield)
7. waitAfter 2 h
8. concentrationthe mixture was concentrated
9. additiondiethyl ether was added
10. customthe solid was collected
11. customdried in vacuo