5-cyclopropyl-4-(2,2,2-trifluoro-ethoxy)-pyridine-2-carboxylic acid 、
2R-amino-3,3-dimethyl-butyric acid tert-butyl ester 以isolated (490 mg, 92%)的产率得到tert-butyl 2-[[5-cyclopropyl-4-(2,2,2-trifluoroethoxy)pyridine-2-carbonyl]amino]-3,3-dimethyl-butanoate