1-Tetrazolylacetic acid → 4-((1R,3aS,5aR,5bR,7aR,11aS,11bR,13aR,13bR)-3a-(2-(1H-tetrazol-1-yl)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 33% 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 1-H-tetrazole-1-acetic acid was used instead of 3-(dimethylamino)propionic acid hydrochloride in Step 1. LCMS: m/e 638.7 (M−H)−, 1.98 min (method 6). 1H NMR (500 MHz, 1:1 CDCl3:MeOD) δ=9.10 (s, 1H), 7.93 (d, J=8.2 Hz, 2H), 7.39 (s, 1H), 7.21 (d, J=8.2 Hz, 2H), 5.30 (dd, J=1.5, 6.1 Hz, 1H), 5.27 (d, J=1.5 Hz, 2H), 4.78 (d, J=1.2 Hz, 1H), 4.65 (s, 1H), 2.71 (dt, J=5.2, 11.1 Hz, 1H), 2.64-2.56 (m, 1H), 2.34 (dd, J=8.1, 12.7 Hz, 1H), 2.13 (dd, J=6.4, 17.1 Hz, 1H), 2.00-1.86 (m, 2H), 1.80 (d, J=11.0 Hz, 1H), 1.74 (br. s., 1H), 1.72 (s, 3H), 1.71-1.66 (m, 1H), 1.62-1.30 (m, 11H), 1.29-1.22 (m, 1H), 1.20-1.14 (m, 1H), 1.12 (s, 3H), 1.10 (d, J=4.3 Hz, 1H), 1.03 (s, 6H), 0.95 (s, 3H), 0.94 (s, 3H).

Provenance & Evidence