Repeated chromatography of the residue (2.3 g)
obtained from hexane-EtOAc (1:1) over Sephadex LH-20
(hexane-MeOH-CHCl3, 2:1:1) furnished 93 mg of 19-oxodihydroatisine
(2), 5 mg of 22-O-acetyl-19-oxodihydroatisine (3),
and 76 mg of 5.
4 Fraction F2, after crystallization (EtOAcMeOH,
9:1) yielded 0.8 g of pure 4.
4 The mother liquors, after
separation of azitine, were rechromatographed on alumina
preparative plates (hexane-EtOAc, 2:1, twice). Two bands
were cut
Repeated chromatography of the residue (2.3 g)obtained from hexane-EtOAc (1:1) over Sephadex LH-20(hexane-MeOH-CHCl3, 2:1:1) furnished 93 mg of 19-oxodihydroatisine(2), 5 mg of 22-O-acetyl-19-oxodihydroatisine (3),and 76 mg of 5.4 Fraction F2, after crystallization (EtOAcMeOH,9:1) yielded 0.8 g of pure 4.4 The mother liquors, afterseparation of azitine, were rechromatographed on aluminapreparative plates (hexane-EtOAc, 2:1, twice). Two bandswere cut
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