Trifluoroacetic acid → 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a-(piperidin-3-ylmethylamino)-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)benzoic acid

Participants

Reaction Steps

To a solution of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-((1-(tert-butoxycarbonyl)piperidin-3-yl)methylamino)-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)benzoic acid (0.019 g, 0.026 mmol) in DCM (1 mL) was added TFA (0.25 mL, 3.24 mmol). The mixture was stirred at rt for 1.75 h. Then, the mixture was concentrated under reduced pressure and purified by prep HPLC to give the title compound (14.2 mg, 0.021 mmol, 81% yield) as a white solid. LCMS: m/e 627.6 (M+H)+, 1.50 min (method 2). 1H NMR (500 MHz, Acetic acid d4) δ ppm 8.04 (2H, d, J=8.2 Hz), 7.30 (2H, d, J=7.9 Hz), 5.37 (1H, s), 4.85 (1H, d, J=5.5 Hz), 4.75 (1H, s), 2.98-3.83 (6H, m), 2.82-2.91 (1H, m), 2.57-2.72 (1H, m), 0.85-2.33 (44H, m).

Provenance & Evidence