4-Methylmorpholine → N-{[4-((2R,3R)-1-(4-fluorophenyl)-3-{[2-(4-fluorophenyl)-2-hydroxyethyl]thio}-4-oxoazetidin-2-yl)phenoxy]acetyl}glycyl-3-cyclohexyl-D-alanine

Participants

Reaction Steps

N-{[4-((2R,3R)-1-(4-fluorophenyl)-3-{[2-(4-fluorophenyl)-2-oxoethyl]thio}-4-oxoazetidin-2-yl)phenoxy]acetyl}glycine (30 mg, 0.0555 mmol) and N-methylmorpholine (30 mg, 0.296 mmol) were dissolved in DMF (0.5 ml). TBTU (23 mg, 0.0717 mmol) was added and the mixture was stirred for 15 min at room temperature. 3-Cyclohexyl-D-alanine (15 mg, 0.0876 mmol) was added and the stirring was continued overnight at room temperature. The solvent was evaporated under reduced pressure and the residue was dissolved in methanol (1 ml). NaBH4 (10 mg, 0.264 mmol) was added and the mixture was stirred for 10 min at room temperature. Three drops of acetic acid was added to the reaction mixture. The product was isolated by preparative HPLC using acetonitrile/ammonium acetate buffer (40:60) as eluent. After freeze-drying 19 mg (49%) of the title compound was obtained. 1H-NMR, 300 MHz, DMSO): 0.68-0.93 (m, 2H), 1.0-1.75 (m, 1H), 2.78-3.00 (m, 2H), 3.73 (s, 2H), 4.00-4.14 (m, 1H), 4.23-4.35 (m, 1H), 4.51 (s, 2H), 4.65-4.78 (m, 1H), 4.99-5.09 (m, 1H), 6.90-7.44 (m, 12H), 7.72-7.86 (m, 1H), 8.26 (t, 1H).

Provenance & Evidence