Triethylamine → N-[1-(4-phenoxybutan-1-yl)piperidin-4-ylmethyl]-5-thia-1,8b-diazaacenaphthylene-4-carboxamide

To a solution of 0.58 g (1.5 mM) of N-(piperidin-4-ylmethyl)-5-thia-1,8b-diazaacenaphthylene-4-carboxamide dihydrochloride and 1.0 ml (27.5 mM) of triethylamine in ethanol (6 ml) was added 0.45 g (1.96 mM) of 4-phenoxybutyl bromide at room temperature and the mixture was refluxed under nitrogen for 14 hours. To this reaction mixture was further added 0.23 g (1.0 mM) of 4-phenoxybutyl bromide and the mixture was refluxed for 6 hours. The solvent was then distilled off under reduced pressure and the residue was diluted with water and extracted with chloroform. The organic layer was washed with saturated aqueous solution of sodium chloride and dried over MgSO4. The resulting crude product was purified by column chromatography (methanol/chloroform=1/15-1/10-1/5) to provide the title compound.