Reaction Steps
To a stirred solution of (1R,3aS,5aR,5bR,7aR,9S,11aR,11bR,13aR,13bR)-3a-((1R,3S)-2,2-dimethyl-3-(pyrrolidine-1-carbonyl)cyclobutylcarbamoyl)-5a,5b,8,8,11a-pentamethyl-1-(prop-1-en-2-yl)icosahydro-1H-cyclopenta[a]chrysen-9-yl acetate (Example 43, 0.350 g, 0.517 mmol) in MeOH:THF (2:1) (30 ml) 2N NaOH (10 ml) was added at 0° C. and allowed to stir at room temperature for about 16 hours. After completion of the reaction (monitored by TLC), the volatile was evaporated and the aqueous layer was extracted with ethyl acetate and the organic layer was washed with water, brine and dried over Na2SO4 then the solvent was evaporated and the resulting crude was stirred in hexane and the resulting solid was obtained which was filtered and dried under vacuum to afford the title compound. Wt: 0.220 g: Yield: 67%; 1H NMR (300 MHz, CDCl3): δ 6.27 (d, 1H, J=8.1 Hz), 4.72 (s, 1H), 4.57 (s, 1H), 4.17-4.07 (m, 1H), 3.56-3.11 (m, 4H), 3.19-3.09 (m, 2H), 2.82-2.76 (m, 1H), 2.57-2.43 (m, 1H), 2.39-2.18 (m, 2H), 2.01-1.72 (m, 7H), 1.67 (s, 3H), 1.61-1.11 (m, 22H), 0.96, 0.93, 0.87, 0.81, 0.74 (s, 18H); Mass: [M+1]+ 635 (5%), [M+Na]+ 657 (100%); IR (KBr, cm−1): 3390, 3071, 2947, 2869, 1617, 1455, 1369, 1341, 1250, 1194, 1168, 1108, 1034, 921, 880; M.R: 176.3° C.-180.9° C.; HPLC: 98.9%.
