tert-butyl 3-(3-amino-2-methylphenyl)propanoate 、
(2S,3R)-3-methyl-2-{4-[(5-oxo-2-phenyl-5,6-dihydro-4H-1,3,4-oxadiazin-4-yl)methyl]phenyl}pentanoic acid 在
吡啶 、 N-[(dimethylamino)-3-oxo-1H-1,2,3-triazolo[4,5-b]pyridin-1-yl-methylene]-N-methylmethanaminium hexafluorophosphate 作用下,
以
N,N-二甲基甲酰胺 为溶剂,
以78%的产率得到tert-butyl 3-(2-methyl-3-{[(2S,3R)-3-methyl-2-{4-[(5-oxo-2-phenyl-5,6-dihydro-4H-1,3,4-oxadiazin-4-yl)methyl]phenyl}pentanoyl]amino}phenyl)propanoate