反应详情

温度

110 °C

To a solution of 4-[3-(N-hydroxycarbamimidoyl)-phenoxazin-10-yl]-piperidine-1-carboxylic acid tert-butyl ester, 1b (0.13 g; 0.31 mmol) in dioxane (5 mL) was added 1,1′-carbonyldiimidazole (75 mg; 0.46 mmol), and the mixture was stirred at 110° C. for 4 hr. The mixture was allowed to cool to rt, and treated with 4N HCl in dioxane (5 mL). The mixture was stirred at rt for 16 hr and evaporated. The residue was suspended in methanol, and the solid was removed via filtration. The filtrate was purified via reverse phase HPLC (eluent gradient: 20 to 40% CH3CN in water containing 0.1% TFA) to yield 8.8 mg (14.4%) of 3-(10-piperidin-4-yl-10H-phenoxazin-3-yl)-4H-[1,2,4]oxadiazol-5-one, 2b as a TFA salt. MS m/z (MH+) 351.1.

1. temperatureto cool to rt
2. stirringThe mixture was stirred at rt for 16 hr
3. customevaporated
4. customthe solid was removed via filtration
5. customThe filtrate was purified via reverse phase HPLC (eluent gradient: 20 to 40% CH3CN in water containing 0.1% TFA)