Reaction Steps
To a solution of methyl 4-((E)-2-((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)vinyl)benzoate (35 mg, 0.048 mmol) in dioxane (2 mL) and MeOH (1 mL) was added 1N NaOH (1 mL, 1 mmol). The mixture was stirred at 50° C. for 2 h. The crude product was purified by prep HPLC (method 4) to give 4-((E)-2-((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)vinyl)benzoic acid as a white solid (12 mg, 35.0%). MS: m/e 717.5 (M+H)+, 2.798 min (method 4). 1H NMR (400 MHz, CHLOROFORM-d) δ 8.08-7.95 (m, 2H), 7.47 (br. s., 2H), 6.98-6.83 (m, 1H), 6.77-6.64 (m, 1H), 5.87 (d, J=4.8 Hz, 1H), 4.72 (br. s., 1H), 4.61 (br. s., 1H), 3.27-3.06 (m, 8H), 2.95 (d, J=7.3 Hz, 2H), 2.86-2.62 (m, 3H), 2.23-2.00 (m, 3H), 1.98-1.79 (m, 4H), 1.73 (br. s., 3H), 1.66-1.50 (m, 5H), 1.48-1.18 (m, 10H), 1.11 (s, 3H), 1.09-1.05 (m, 3H), 1.03-0.96 (m, 6H), 0.76 (s, 3H).
