反应详情

To a solution of N-(tert-butoxycarbonyl)-L-phenylalanine (98.5 mg, 0.371 mmol) in N-methylpyrrolidinone (2.2 mL) was added N,N,N′,N′-tetramethyl-O-(7-azabenzotriazol-1-yl)uronium hexafluorophosphate (128 mg, 0.337 mmol) and N,N-diisopropylethylamine (180 μL, 0.001 mol) and premixed for 5 minutes. To the solution was added (2S)-2-amino-3-[4-(1,1-dioxido-3-oxo-2,3-dihydroisothiazol-5-yl)phenyl]propanoic acid (100 mg, 0.338 mmol) with several drops of DMSO to dissolve and the mixture was stirred overnight. The product was purified by preparative LCMS to afford the desired product (96 mg, 52%). 1H NMR (400 MHz, CD3OD): δ 7.81 (d, J=8.2, 2H), 7.42 (d, J=8.2, 2H), 7.18–7.36 (m, 5H), 6.98 (s, 1H), 4.70–4.73 (m, 1H), 4.26–4.30 (m, 1H), 3.02–3.13 (m, 3H), 2.71–2.76 (m, 1H), 1.33 (s, 9H); LCMS found for C26H9N3O8SNa (M+Na)+: m/z=566.0.

1. additionpremixed for 5 minutes
2. dissolutionto dissolve
3. customThe product was purified by preparative LCMS