反应详情

0.46 g (1.32 mmol) (S)—N—((S)-5-cyclopropylmethyl-6-oxo-6,7-dihydro-5H-dibenzo[b,d]azepin-7-yl)-2-hydroxy-propionamide in 15 ml dichloromethane were stirred with 213 μl (2.64 mmol) pyridine and 0.33 g (1.58 mmol) 4-nitrophenyl chloroformate at room temperature overnight. Chromatography on silicagel with ethylacetate/cyclohexane (0-100/100-0) gave 0.63 mg (92%) carbonic acid (S)-1-((S)-5-cyclopropylmethyl-6-oxo-6,7-dihydro-5H-dibenzo[b,d]azepin-7-ylcarbamoyl)-ethyl ester 4-nitro-phenyl ester as a white foam; MS: m/e: 516.5 (M+H+), [α] 589=−164° (0.94% in MeOH).