[NH2:1][C:2](=[O:22])[CH:3]([C:15]1[CH:20]=[CH:19][C:18]([Br:21])=[CH:17][CH:16]=1)[CH2:4][C:5]([O:7]CC1C=CC=CC=1)=[O:6]>C(O)C.C(OCC)(=O)C.[Pt](=O)=O>[NH2:1][C:2](=[O:22])[CH:3]([C:15]1[CH:20]=[CH:19][C:18]([Br:21])=[CH:17][CH:16]=1)[CH2:4][C:5]([OH:7])=[O:6]A suspension of benzyl 4-amino-3-(4-bromophenyl)-4-oxobutanoate (1.14 g, 3.16 mmol) and platinum(IV) oxide (30 mg) in ethanol/ethyl acetate (5:1; 120 mL) was stirred under an hydrogen atmosphere for 2 h. After replacement of hydrogen with nitrogen the crude reaction mixture was filtered through a thin pad of celite and the filtrate evaporated to dryness to give the title compound as a white solid (671 mg, 78%). LC/MS: 2.41 min; z/e 271 and 273, calcd (M+1) 271 and 271. 1H NMR (400 MHz: DMSO-d6): 7.50 (2H), 7.25 (2H), 3.95 (1H), 2.95 (1H), 2.45 (1H).
Wird geladen…