5-Phenyl-4-(trifluoromethyl)isoxazole-3-carbonyl fluoride, Int-II-D (78 mg, 0.3 mmol) was dissolved in acetonitrile (5 mL) and (S)-ethyl 1-((S)-2-hydroxy-2-(4-((Z)—N′-hydroxycarbamimidoyl)phenyl)ethyl)piperidine-3-carboxylate, Preparation 14B (100 mg, 0.298 mmol) was added. After 2 hours, 1M TBAF in THF (298 μL, 0.298 mmol) was added and the reaction mixture was stirred overnight. The reaction mixture was diluted with ethyl acetate and washed with H2O. The organic layer was dried with MgSO4, filtered, and concentrated. The resulting material was purified on a silica gel cartridge using an EtOAc/hexanes gradient to yield 67 mg of (S)-ethyl 1-((S)-2-hydroxy-2-(4-(5-(5-phenyl-4-(trifluoromethyl)isoxazol-3-yl)-1,2,4-oxadiazol-3-yl)phenyl)ethyl)piperidine-3-carboxylate. MS (m+1)=557. HPLC Peak RT=3.32 minutes (Analytical Method A).
