反应详情

温度

70 °C

To a solution of (6R,6aS,14aR)-methyl 1,6,8,14a-tetrahydroxy-11-((2S,3R,4R,5R,6S)-4-hydroxy-3,5-dimethoxy-6-methyltetrahydro-2H-pyran-2-ylamino)-6a-methoxy-3-methyl-7,9,12,14-tetraoxo-5,6,6a,7,9,12,14,14a-octahydrobenzo[a]tetracene-2-carboxylate (100 mg, 0.14 mmol) in acetonitrile (1 mL) was added zirconyl(IV) nitrate hydrate (36 mg, 0.16 mmol). The reaction mixture was heated to 70° C. for 1 h. After cooled to room temperature, the reaction mixture was filtered through a micro filter and the filtrate was concentrated under reduced pressure. The crude material was purified by preparative TLC (silica gel, 96:4 chloroform/methanol) and semi-preparative HPLC to afford (6R,6aS,14aR)-methyl 1,6,8,14a-tetrahydroxy-11-((2S,3R,4R,5R,6S)-4-hydroxy-3,5-dimethoxy-6-methyltetrahydro-2H-pyran-2-ylamino)-6a-methoxy-3-methyl-4-nitro-7,9,12,14-tetraoxo-5,6,6a,7,9,12,14,14a-octahydrobenzo[a]tetracene-2-carboxylate (34 mg, 33%) as a dark red solid: 1H NMR (500 MHz, CDCl3) δ 14.23 (s, 1H), 12.27 (br s, 1H), 8.19 (s, 1H), 6.86 (d, J=8.0 Hz, 1H), 5.89 (s, 1H), 5.31 (s, 1H), 5.19 (s, 1H), 4.69 (d, J=8.5 Hz, 1H), 4.61 (s, 1H), 3.91 (s, 3H), 3.79 (s, 3H), 3.76-3.65 (m, 2H), 3.61 (s, 3H), 3.49 (dd, J=19.5, 6.5 Hz, 1H), 3.40 (s, 3H), 3.39-3.35 (m, 1H), 3.28 (d, J=19.5 Hz, 1H), 3.13 (t, J=9.5 Hz, 1H), 2.47 (d, J=4.5 Hz, 1H), 2.40 (s, 3H), 1.36 (d, J=6.0 Hz, 3H); MS (ESI+) m/z 743 (M+H); HPLC 98.0% (AUC), tR 13.79 min.

1. temperatureAfter cooled to room temperature
2. filtrationthe reaction mixture was filtered through
3. filtrationa micro filter
4. concentrationthe filtrate was concentrated under reduced pressure
5. customThe crude material was purified by preparative TLC (silica gel, 96:4 chloroform/methanol) and semi-preparative HPLC