4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-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)-2-fluorobenzoic acid → 4-((1S,3aS,5aR,5bR,7aS,9S,11aS,11bR,13aR,13bR)-3a-amino-1-isopropyl-5a,5b,8,8,11a-pentamethylicosahydro-1H-cyclopenta[a]chrysen-9-yl)benzoic acid

Participants

Reaction Steps

The title compound was prepared following the method described above for the synthesis of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-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)-2-fluorobenzoic acid using methyl 4-((1S,3aS,5aR,5bR,7aS,9S,11aS,11bR,13aR,13bR)-3a-amino-1-isopropyl-5a,5b,8,8,11a-pentamethylicosahydro-1H-cyclopenta[a]chrysen-9-yl)benzoate as the starting material in Step 5. The product was isolated as a white solid (12 mg, 47%). LCMS: m/e 532.43 (M−H)−, 2.37 min (method 10). 1H NMR (500 MHz, METHANOL-d4) δ 7.84 (d, J=8.2 Hz, 2H), 7.19 (d, J=8.2 Hz, 2H), 2.42 (dd, J=13.0, 2.9 Hz, 1H), 2.18 (qd, J=13.3, 3.1 Hz, 1H), 2.07-1.24 (m, 25H), 1.16 (s, 3H), 1.07 (s, 3H), 1.03 (s, 3H), 0.93 (d, J=6.7 Hz, 3H), 0.83 (d, J=6.7 Hz, 3H), 0.79 (s, 3H), 0.74 (s, 3H).

Provenance & Evidence