(5-Carboxypentyl)triphenylphosphanium bromide → (4S)-(E)-7-[4-[4-[[(4-Cyclohexylbutyl)amino]carbonyl]-4,5-dihydro-2-oxazolyl]phenyl]-7-(3-pyridyl)hept-6-enoic Acid

Beteiligte Stoffe

Reaktionsschritte

Using the method described above at example 18-G, 1.472 g (3.4 mmol) of (4S)-4,5-dihydro-2-[4-(3-pyridylcarbonyl)phenyl]oxazole-4-[N-(4-cyclohexylbutyl)]-L-serinamide was treated with 3.08 g (6.8 mmol) of (5-carboxypentyl)triphenylphosphonium bromide and 13.6 mL (13.6 mmol) of 1.0 M t-BuOK in 10.0 mL of THF at 0° C. for 2.5 hr. Preparative HPLC with MeOH-AcOH-CH2Cl2 (3:0.5:96.5) yielded ~700 mg (38%) of the title product and ~670 mg (37%) of the β-elimination Wittig product (less polar material) (E)-7-[4-[[[1-[[(4-cyclohexylbutyl)amino]carbonyl]-eth-1-enyl]amino]carbonyl]phenyl]-7-(3-pyridyl)-hept-6-enoic acid (311030): mp 61-63° C.; 1H NMR (CDCl3) δ9.05 (s, 1H), 8.58 (s, 1H), 8.48 (d, J=3.3 Hz, 1H), 7.89 (d, J=8.2 Hz, 2H), 7.43 (br d, J=8.0 Hz, 1H), 7.26 (d, J=8.0 Hz, 2H), 7.25 (buried, 1H), 6.63 (d, J=1.1 Hz, 1H), 6.55 (br s, 1H), 6.21 (t, J=7.4 Hz, 1H), 5.35 (s, 1H), 3.37 (dt, J=6.8, 6.3 Hz, 2H), 2.32 (dd, J=7.1, 6.9 Hz, 2H), 2.18 (ddd, J=7.3, 7.2, 7.1 Hz, 2H), 1.69-0.83 (m, 21H); FDMS 532 (M+1). Anal. (C32H41N3O4) C, H, N.

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