5-cyclopropyl-4-((S)-2,2,2-trifluoro-1-methyl-ethoxy)-pyridine-2-carboxylic acid 、
tert-butyl 3-amino-3-cyclopropyl-butanoate 以isolated (467 mg, 56%)的产率得到tert-butyl 3-cyclopropyl-3-[[5-cyclopropyl-4-[(1S)-2,2,2-trifluoro-1-methyl-ethoxy]pyridine-2-carbonyl]amino]butanoate