tert-butyl N-[(4'-hydroxy-1,1'-biphenyl-4-yl)sulfonyl]-D-valinate 、
2-氯-5-三氟甲基吡啶 在
potassium carbonate 作用下,
以
DMF (N,N-dimethyl-formamide) 为溶剂,
反应 4.5h,
以74%的产率得到(R)-3-methyl-2-[4'-(5-trifluoromethyl-pyridin-2-yloxy)-biphenyl-4-sulfonylamino]-butyric acid tert-butyl ester