Dimethylformamide → 2-(3-Hydroxypiperidino)-8-[(E)-2-(4-isopropyl-1,3-thiazol-2-yl)-1-ethenyl]-4H-pyrido[1,2-a]pyrimidin-4-one

Participants

Reaction Steps

The 2-hydroxy-8-[(E)-2-(4-isopropyl-1,3-thiazol-2-yl)-1-ethenyl]-4H-pyrido[1,2-a]-pyrimidin-4-one (1.00 g, 3.19 mmol) obtained in (E) was dissolved in anhydrous tetrahydrofuran (15.0 ml) and anhydrous dimethylformamide (15.0 ml), added with 4-dimethylaminopyridine (585 mg, 4.79 mmol) and p-toluenesulfonyl chloride (730 mg, 3.83 mmol), and then the mixture was stirred at room temperature for 50 minutes. Subsequently, the reaction solution was added with 3-hydroxypiperidine (646 mg, 6.38 mmol) and stirred at room temperature for 16 hours, and then added with 3-hydroxypiperidine (968 mg, 9.57 mmol) and stirred at 60° C. for 1.5 hours. After the reaction mixture was concentrated, the residue was purified by silica gel column chromatography (chloroform:methanol=100:0→100:1→100:2→100:5→100:10, v/v) to obtain the title compound (865 mg, 68%).

Provenance & Evidence