反应详情

A solution of anhydride 1 (145 mg, 0.4 mmol) in glacial acetic acid (10 mL) was refluxed with hydrazine hydrate (0.023 mL, 0.48 mmol) for 24 h under nitrogen and then poured, after cooling, into ice water. The resulting precipitate was filtered and dried under reduced pressure. The residue was purified by column chromatography on silica gel using CH2Cl2/MeOH (30:1 to 20:1, v/v) to give 25 (143 mg, 86%) as a yellow solid. mp 281-283° C.; 1H NMR (CDCl3) δ 8.34 (s, 1H, H4), 7.69 (d, 1H, H5, J=8.7 Hz), 7.46 (s, 1H, NHAc), 7.38 (d, 1H, H6, J=8.7 Hz), 6.84-6.87 (m, 3H, H2′+H5′+H6′), 6.06 (AB, 2H, 3′,4′-OCH2O—, Δδ=16.5 Hz, J=1.5 Hz), 5.98 (AB, 2H, 7,8-OCH2O—, Δδ=5.4 Hz, J=1.2 Hz), 2.17 (s, 3H, NHCOCH3); MS (EI) m/z 418 [M]+.

1. additionpoured
2. filtrationThe resulting precipitate was filtered
3. customdried under reduced pressure
4. customThe residue was purified by column chromatography on silica gel