Boronic Acid → (1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-[4-[(4-hydroxy-4-oxo-butanoyl)amino]phenyl]-1-isopropenyl-5a,5b,8,8,11a-pentamethyl-1,2,3,4,5,6,7,7a,11,11b,12,13,13a,13b-tetradecahydrocyclopenta[a]chrysene-3a-carboxylic acid

Participants

Reaction Steps

The title compound was prepared following the methods described above for (1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-9-(4-(2-carboxyethyl)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]chrysene-3a-carboxylic acid (example 4a) using 4-(4-boronophenylamino)-4-oxobutanoic acid as the reactant boronic acid. The product was isolated as a white solid (2.98 mg, 9%). LCMS: m/e 628.63 (M−H)−, 3.71 min (method 2). 1H NMR (599 MHz, DMSO-D6_CDCl3) δ ppm 0.91 (s, 3H), 0.93 (s, 3H), 0.98 (s, 3H), 0.99 (s, 3H), 1.02 (s, 3H), 1.03-1.71 (m, 17H), 1.71 (s, 3H), 1.84-1.93 (m, 2H), 2.09 (dd, J=17.87, 5.57 Hz, 1H), 2.20 (d, J=12.30 Hz, 1H), 2.29-2.39 (m, 1H), 2.59-2.62 (m, 2H), 2.97-3.10 (m, 1H), 3.30-3.33 (m, 2H), 4.61 (br. s, 1H), 4.74 (s, 1H), 5.24 (d, J=5.27 Hz, 1H), 7.03 (d, J=8.79 Hz, 2H), 7.51 (d, J=8.20 Hz, 2H).

Provenance & Evidence