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

Participants

Reaction Steps

To a solution of Compound (39a) (Step-1 in Example 44) (303 mg, 0.53 mmol) in 10 ml of methanol containing 1% water was added 30 mg of 10% palladium-carbon, followed by catalytic reduction under atomospheric pressure for 2.5 hours. After the catalyst was removed by filtration, the filtrate was concentrated under reduced pressure. The residue was purified by a column chromatography (silica gel 5 g; ethyl acetate) to give 234 mg (91%) of Compound (55a).

Provenance & Evidence