合成路线1

2'-Hydroxyacetophenone (I) is protected as the silyl ether (II) employing t-butyldimethylsilyl chloride and imidazole. Condensation of acetophenone (II) with 3-nitrobenzaldehyde (III) and malononitrile in the presence of ammonium acetate gives rise to the cyanopyridine (IV). The nitro group of (IV) is then reduced to the corresponding amine (V) by catalytic hydrogenation over Pd/C. 3-Piperidinylpropionic acid (VI) is then activated as the acid chloride (VII) upon treatment with oxalyl chloride. Subsequent coupling of acid chloride (VII) with amine (V) furnishes amide (VIII). Finally, desilylation of (VIII) by means of either tetrabutylammonium fluoride or HCl in dioxane leads to the title compound. (1,2)