(R)-ethyl 4-(5'-fluoro-2'-methoxy-[1,1'-biphenyl]-4-yl)-3-(2-hydrazinyl-2-oxoacetamido)butanoate 、
Carbonyldiimidazole 在
silica gel 、
ethyl acetate n-hexane 作用下,
以
四氢呋喃 为溶剂,
反应 24.0h,
以to afford (R)-ethyl 4-(5′-fluoro-2′-methoxy-[1,1′-biphenyl]-4-yl)-3-(5-oxo-4,5-dihydro-1,3,4-oxadiazole-2-carboxamido)butanoate 4.25 g (84%)的产率得到(R)-ethyl 4-(5'-fluoro-2'-methoxy-[1,1'-biphenyl]-4-yl)-3-(5-oxo-4,5-dihydro-1,3,4-oxadiazole-2-carboxamido)butanoate