反応手順
The title compound was prepared in 47% 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-((2-fluoropyridin-4-yl)methylamino)-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 5-fluoro-2-formylpyridine was used instead of 2-fluoropyridine-4-carboxaldehyde in Step 1. LCMS: m/e 639.5 (M+H)+, 3.33 min (method 6). 1H NMR (500 MHz, 1:1 CDCl3:MeOD) δ=8.46 (d, J=2.7 Hz, 1H), 7.93 (d, J=8.2 Hz, 2H), 7.68 (dt, J=2.7, 8.2 Hz, 1H), 7.53 (dd, J=4.1, 8.7 Hz, 1H), 7.21 (d, J=8.5 Hz, 2H), 5.31 (dd, J=1.7, 6.3 Hz, 1H), 4.83 (s, 1H), 4.74 (s, 1H), 4.49 (d, J=15.3 Hz, 1H), 4.32 (d, J=15.0 Hz, 1H), 2.78 (dt, J=5.3, 10.9 Hz, 1H), 2.22-2.06 (m, 5H), 1.96 (dt, J=3.4, 12.2 Hz, 1H), 1.89-1.82 (m, 1H), 1.80 (d, J=10.7 Hz, 2H), 1.76 (s, 3H), 1.74-1.66 (m, 2H), 1.64-1.54 (m, 4H), 1.53-1.47 (m, 2H), 1.46-1.42 (m, 1H), 1.41-1.37 (m, 1H), 1.33 (s, 3H), 1.29 (dd, J=3.8, 9.9 Hz, 1H), 1.24 (dd, J=4.1, 13.0 Hz, 1H), 1.13 (s, 3H), 1.07 (s, 3H), 0.97 (s, 3H), 0.95 (s, 3H).
