66 mg of thiazolidinedione are dissolved in 10 ml of tetrahydrofuran and, at −78° C., 0.11 ml of a 2.7 M solution of n-butyllithium in n-hexane is added. The mixture is stirred at −78° C. for 30 minutes, and 150 mg of [cis-3-[2-(4-fluorophenyl)-5-methyloxazol-4-ylmethoxy]cyclohexyl]acetaldehyde, dissolved in 5 ml of tetrahydrofuran, are then added. After 30 minutes of stirring at −78° C., the mixture is allowed to warm to room temperature. 5 ml of 1N hydrochloric acid are added, and the mixture is extracted three times with in each case 20 ml of ethyl acetate. The combined organic phases are dried over magnesium sulfate and the solvent is then removed under reduced pressure. The residue is purified by RP-HPLC. This gives 184 mg of 5-(2-{cis-3-[2-(4-fluorophenyl)-5-methyloxazol-4-ylmethoxy]cyclohexyl-oxy}ethylidene)thiazolidine-2,4-dione as a white solid. C22H23FN2O5S (446.01), MS (ESI): 447 (M+H+).
