Reaction Steps
4-(N—(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-(tert-butoxycarbonyl)phenyl)-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-3a-yl)methyl)sulfamoyl)benzoic acid (10 mg, 0.013 mmol) from Step 1 was dissolved in dioxane (1 ml) and MeOH (5 ml) sodium hydroxide (10.20 mg, 0.255 mmol) (powder) was added followed by 5 drops of water. The resulting suspension was stirred at 70° C. for 6 h. After the reaction was completed, all volatile material was removed in vacuo. The residue was re-dissolved in MeOH and purified by prep. HPLC to afford 4-(N—(((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-carboxyphenyl)-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-3a-yl)methyl)sulfamoyl)benzoic acid as a white solid (1.8 mg, 18.4%). LCMS: m/e 728.2 (MH+), 2.11 min (method 3). 1H NMR (400 MHz, MeOD) δ ppm 8.24 (m, J=8.5 Hz, 2H), 8.01 (m, J=8.5 Hz, 2H), 7.94 (m, J=8.3 Hz, 2H), 7.24 (m, J=8.3 Hz, 2H), 5.31 (d, J=4.3 Hz, 1H), 4.70 (d, J=2.3 Hz, 1H), 4.59 (s, 1H), 3.05 (s, 1H), 2.62 (d, J=13.1 Hz, 1H), 2.37 (br. s., 1H), 2.11 (m, 1H), 1.76-2.01 (m, 4H), 1.65-1.76 (m, 6H), 1.53-1.65 (m, 4H), 1.44 (br. s., 5H), 1.31 (d, J=2.8 Hz, 6H), 1.03 (s, 6H), 1.01 (s, 3H), 0.99 (s, 3H), 0.96 (s, 3H).
