A stirred mixture of [1-(5-formyl-isoxazol-3-yl)-3-methyl-butyl]-carbamic acid benzyl ester (407 mg, 1.3 mmol), pyridine (10 ml) and ethyl hydrogen malonate (255 mg, 1.9 mmol) was warmed to 55° C. After 2 days the mixture was cooled to room temperature, poured into water and extracted into EtOAc (3×). The combined organics were washed with 1N HCl, water, and brine; dried over NaSO4, filtered and concentrated under reduced pressure to give 480 mg of a yellow oil. Purification by Flash 40(small) chromatography eluting with 1:3 EtOAc/hexane gave 220 mg of the title compound as a light yellow oil. MS [M+1]+ 387.
