Acetyl chloride → (6aR,7S,9aS,11S,13aS)-11-acetylamino-5-benzyloxy-2-(t-butoxycarbonyl)-2,3,6,6a,7,8,9,9a,10,11,12,13-dodecahydro-6a,7,10,10-tetramethyl-3-oxo-1H-benzo[8,8a][1]benzopyrano [2,3-e] isoindole

Participants

Reaction Steps

Under nitrogen, 25 μl (0.18 mmol) of triethylamine and 8 μl (0.11 mmol) of acetyl chloride was added to a solution of Compound (45a) (50 mg, 0.087 mmol) in 2.0 ml of dry dichloromethane under ice-cooling, and the mixture stirred for 40 min at the same temperature. After addition of ice-water, the reaction was extracted with ethyl acetate. The extract was washed with aqueous saturated sodium hydrogen carbonate and water, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by a preparative thin layer chromatography (Merck, Kieselgel 60 F254, 0.5 mm; chloroform:methanol=30:1) to give 44 mg (82%) of Compound (45b).

Provenance & Evidence