Triethylamine → (2S,3S,4S,5R,6R)-6-((4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-(1,1-dioxidothiomorpholino)ethyl)amino)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoyl)oxy)-3,4,5-trihydroxytetrahydro-2H-pyran-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of (2S,3S,4S,5R,6R)-benzyl 6-((4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((2-(1,1-dioxidothiomorpholino)ethyl)amino)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)-2,3,3a,4,5,5a,5b,6,7,7a,8,11,11a,11b,12,13,13a,13b-octadecahydro-1H-cyclopenta[a]chrysen-9-yl)benzoyl)oxy)-3,4,5-trihydroxytetrahydro-2H-pyran-2-carboxylate (8 mg, 8.36 mmol), tert-butyldimethylsilane (1.943 mg, 0.017 mmol), palladium acetate (3.75 mg, 0.017 mmol) and triethylamine (5.82 μl, 0.042 mmol) in dichloroethane (1 mL) was heated up at 60° C. for 2 hours. The reaction mixture was cooled to room temperature, filtered and the filtrates were concentrated to provide the residue. To this residue in THF (1.0 mL) was added TBAF (10.93 mg, 0.042 mmol), the reaction mixture was stirred for 1 hours. The reaction mixture was then purified by prep. HPLC to provide the desired product as a colorless oil (4 mg, 52%). LCMS: m/e 867.69 (M+H)+, 2.42 min (method 10). 1H NMR (500 MHz, Acetic) δ 8.06 (d, J=8.2 Hz, 2H), 7.31 (d, J=8.2 Hz, 2H), 5.96 (d, J=7.9 Hz, 1H), 5.37 (d, J=4.4 Hz, 1H), 4.84 (s, 1H), 4.74 (s, 1H), 4.40-4.16 (m, 1H), 4.02-3.76 (m, 3H), 3.46 (d, J=12.3 Hz, 1H), 3.37-3.22 (m, 6H), 3.20-3.11 (m, 3H), 3.07 (br. s., 2H), 3.00-2.82 (m, 1H), 2.37-1.03 (m, 22H), 1.76 (s, 3H), 1.29 (s, 3H), 1.14 (s, 3H), 1.10 (s, 3H), 1.02 (s, 3H), 0.99 (s, 3H).

Provenance & Evidence