反应详情

5-(4-Acetoxyphenyl)-3-benzyl-2-bis(4-nitrophenylsulfonyl)aminopyrazine (c-40) (151 mg, 219 μmol) was suspended in methanol (3 mL), and to this was added 10% (w/v) aqueous solution of sodium hydroxide aqueous (600 μL) while stirring at room temperature and then stirred at 65° C. for 30 min. To this were sequentially added methanol (1 mL) and 10% (w/v) aqueous solution of sodium hydroxide (400 μL) and stirred for an hour. After cooling to room temperature, to this was added 2 M hydrochloric to stop the reaction and extracted twice with ethyl acetate. The organic layer was washed with saturated brine and then dried over anhydrous sodium sulfate. After removing anhydrous sodium sulfate by filtration, the filtrate was concentrated under reduced pressure with a rotary evaporator. The residue was purified by column chromatography (8 g, n-hexane/ethyl acetate=3/2) to give 3-benzyl-5-(4-hydroxyphenyl)-2-[(4-nitrophenyl) sulfonylamino]pyrazine (coelentera-p-nosylamide) (c-36) as an orange solid (88.8 mg, 87.7%). Rf=0.13 (n-hexane/ethyl acetate=3/2). Mp. 176-177.5° C. (dec.). UV (MeOH) λmax (log ε) 338 (4.11), 276.5 (4.42). UV (pH 7.4 PB) λmax (log ε) 347 (4.15), 278.5 (4.49). 1H NMR (400 MHz, DMSO-d6) δ 4.28 (s, 2H), 6.81 (d, J=8.7 Hz, 2H), 7.17-7.25 (m, 1H), 7.29 (s, 4H), 7.81 (d, J=8.6 Hz, 2H), 8.15 (d, J=8.6 Hz, 2H), 8.40 (d, J=8.4 Hz, 2H), 8.52 (s, 1H), 9.81 (s, 1H), 11.25 (s, 1H). IR (KBr, cm−1) 633, 698, 748, 773, 827, 853, 970, 1084, 1121, 1231, 1263, 1277, 1350, 1395, 1501, 1514, 1528, 1611, 3227. HRMS (FAB+) m/z 463.1086 (M+H, C23H19N4O5S requires 463.1076).

1. stirringstirred at 65° C. for 30 min
2. stirringstirred for an hour
3. temperatureAfter cooling to room temperature
4. additionto this was added 2 M hydrochloric
5. customthe reaction
6. extractionextracted twice with ethyl acetate
7. washThe organic layer was washed with saturated brine
8. dry with materialdried over anhydrous sodium sulfate
9. customAfter removing anhydrous sodium sulfate
10. filtrationby filtration
11. concentrationthe filtrate was concentrated under reduced pressure with a rotary evaporator
12. customThe residue was purified by column chromatography (8 g, n-hexane/ethyl acetate=3/2)