N,N′-Carbonyldiimidazole (77 mg, 0.475 mmol) was added to a solution of 2-(2-(4-methoxy-N,2,6-trimethylphenylsulfonamido)-ethoxy)acetic acid (acid unit S2) (150 mg, 0.453 mmol) in methylene chloride (7 ml), and the mixture was stirred for 1 h at room temperature. A solution of 4-(pyridin-3-ylmethyl)piperidin-4-ol dihydrochloride (120 mg, 0.453 mmol) dissolved in methylene chloride (3 ml) and triethylamine (0.18 ml) was then added, and the reaction mixture was stirred overnight at room temperature. Saturated sodium bicarbonate solution (10 ml) was then added to the reaction mixture, and the aqueous phase was then extracted with methylene chloride (20 ml). The combined organic phases were extracted with saturated sodium chloride solution (10 ml), dried with sodium sulfate and concentrated in vacuo. The crude product was purified by flash chromatography with ether/methylene chloride/methanol (10:10:1) and 25% strength ammonia solution. N-(2-(2-(4-Hydroxy-4-(pyridin-3-ylmethyl)piperidin-1-yl)-2-oxoethoxy)ethyl)-4-methoxy-N,2,6-trimethylphenylsulfonamide (140 mg) was dissolved in methyl ethyl ketone (1 ml), and HCl in ether (3 eq.) was added slowly, whereupon a white solid precipitated. After addition of diethyl ether, stirring was carried out for 1 h, while cooling with ice. The solid was filtered off, washed with diethyl ether and dried. Yield: 120 mg (48%). The amine units used in Examples 279 and 280 can be prepared analogously to the synthesis processes described above for amine units A2, A3, A4 and A7 with addition of a corresponding Li organyl or Grignard radical to the corresponding piperidone derivative.
