2-[(2R,6S)-2,6-dimethylmorpholin-4-yl]acetic acid → 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-((2S,6R)-2,6-dimethylmorpholino)acetamido)-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)benzoic acid

Participants

Reaction Steps

The title compound was prepared in 43% yield from methyl 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)benzoate following the same procedure as described for the preparation of 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(3-(dimethylamino)propanamido)-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)benzoic acid, except [(2R,6S)-2,6-dimethylmorpholin-4-yl]acetic acid was used instead of 3-(dimethylamino)propionic acid hydrochloride in Step 1. LCMS: m/e 685.6 (M+H)+, 2.48 min (method 6). 1H NMR (500 MHz, 1:1 CDCl3:MeOD) δ=7.92 (d, J=8.2 Hz, 2H), 7.20 (d, J=8.2 Hz, 2H), 5.29 (dd, J=1.5, 6.1 Hz, 1H), 4.75 (d, J=1.2 Hz, 1H), 3.89 (dd, J=6.3, 9.0 Hz, 2H), 3.64 (br. s., 1H), 3.24 (br. s., 2H), 2.69-2.49 (m, 4H), 2.39 (dd, J=8.1, 12.4 Hz, 1H), 2.13 (dd, J=6.4, 17.1 Hz, 1H), 1.93-1.76 (m, 3H), 1.74 (br. s., 1H), 1.72 (s, 3H), 1.70-1.66 (m, 1H), 1.60-1.42 (m, 8H), 1.42-1.30 (m, 3H), 1.25 (d, J=3.1 Hz, 3H), 1.24 (d, J=2.7 Hz, 3H), 1.18-1.11 (m, 2H), 1.08 (s, 3H), 1.03 (s, 3H), 1.01 (s, 3H), 0.95 (s, 3H), 0.94 (s, 3H).

Provenance & Evidence