CC1[N:3]([C@H:8]2[CH2:12][C@@:11]([C:23]3([OH:27])[CH2:26][CH2:25][CH2:24]3)([C:13]([O:15][CH2:16][C:17]3[CH:22]=[CH:21][CH:20]=[CH:19][CH:18]=3)=[O:14])[CH:10]=[CH:9]2)C(C)=CC=1.Cl.NO.NO.O>CO>[NH2:3][C@H:8]1[CH2:12][C@@:11]([C:23]2([OH:27])[CH2:24][CH2:25][CH2:26]2)([C:13]([O:15][CH2:16][C:17]2[CH:18]=[CH:19][CH:20]=[CH:21][CH:22]=2)=[O:14])[CH:10]=[CH:9]1A mixture of 5.52 g (15.1 mmol) of benzyl (1R,4S)-4-(2,5-dimethyl-1H-pyrrol-1-yl)-1-(1-hydroxycyclobutyl)cyclopent-2-ene-1-carboxylate (Preparation SRT-0229), 8.20 g (120 mmol) of hydroxylamine hydrochloride, and 7.0 mL of 50% aqueous hydroxylamine (100 mmol) in 50 mL of methanol was heated at 68 C for 8 h, then cooled. Sufficient water was added to dissolve the crystals which deposited, and the solution was concentrated under reduced pressure to remove methanol. The resulting mixture was brought to pH ˜10 with aq. NaOH and then extracted with several portions of dichloromethane. The organic phase was dried over Na2SO4 and then concentrated under reduced pressure to afford 4.15 g (96%) of the title amine as a nearly colorless oil, of sufficient purity for the subsequent reaction. 1H NMR (400 MHz, CHLOROFORM-d) δ ppm 1.42-1.53 (m, 1H) 1.85 (dd, 1H) 1.88-2.08 (m, 4H) 2.19-2.27 (m, 1H) 2.46 (dd, J=14.5, 8.3 Hz, 1H) 3.97-4.02 (m, 1H) 4.70 (s, 1H) 5.16 (s, 2H) 5.84 (dd, J=5.6, 1.6 Hz, 1H) 5.98 (dd, J=5.6, 2.1 Hz, 1H) 7.31-7.38 (m, 5H). LC-MS ES+ 288.2.
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