Reaction Steps
To a solution of methyl 2-fluoro-4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a-((2-(4-(methylsulfonyl)piperazin-1-yl)ethyl)amino)-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)benzoate (0.056 g, 0.074 mmol) in 1,4-dioxane (2 mL) was added NaOH (1N) (0.372 mL, 0.372 mmol). The mixture was heated to 60° C. for 6.5 h then was cooled to rt. The mixture was diluted with methanol and 1,4-dioxane, was filtered through a plug of glass wool and was purified by prep HPLC. The fractions containing the expected product were combined and were concentrated under reduced pressure to give 2-fluoro-4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-5a,5b,8,8,11a-pentamethyl-3a-((2-(4-(methylsulfonyl)piperazin-1-yl)ethyl)amino)-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 (30.1 mg, 0.039 mmol, 52.0% yield) as a white solid. LCMS: m/e 738.6 (M+H)+, 1.66 min (method 2). 1H NMR (400 MHz, Acetic acid d4) 67.92 (t, J=7.9 Hz, 1H), 7.04 (dd, J=8.0, 1.5 Hz, 1H), 7.01-6.96 (m, 1H), 5.38 (d, J=5.0 Hz, 1H), 4.81 (s, 1H), 4.70 (s, 1H), 3.59-3.25 (m, 8H), 3.15 (br. s., 4H), 2.90 (s, 3H), 2.94-2.81 (m, 1H), 1.72 (s, 3H), 1.21 (s, 3H), 1.09 (s, 3H), 1.04 (s, 3H), 0.99 (s, 3H), 0.97 (s, 3H), 2.23-0.83 (m, 22H).
