4-Hydroxy-N-[4-methoxy-7-(4-morpholinyl)-2-benzothiazolyl]-4-methyl-1-piperidinecarboxamide

383869-80-5

3970-68-1

870070-55-6

Phenyl (4-methoxy-7-morpholin-4-ylbenzo[D]thiazol-2-yl) carbamate (3.2 g, 8.3 mmol) and 4-methyl-4-hydroxypiperidine were used as raw materials and both were dissolved in trichloromethane (50 ml) in the presence of N-ethyl diisopropylamine (4.4 ml, 25 mmol). Subsequently, a mixed solution of trichloromethane (3 ml) and tetrahydrofuran (3 ml) of 4-hydroxy-4-methylpiperidine was added to this solution. The reaction mixture was heated to reflux for 1 hour. After completion of the reaction, the mixture was cooled to room temperature and washed sequentially with saturated aqueous sodium carbonate solution (15 ml) and water (2 x 5 ml). The organic phase was dried over magnesium sulfate and the solvent was concentrated under reduced pressure, the resulting crude product was recrystallized from ethanol to afford the target compound 4-hydroxy-N-[4-methoxy-7-(4-morpholinyl)-2-benzothiazolyl]-4-methyl-1-piperidinecarboxamide as white crystals in 78% yield, melting point 236 °C. Mass spectral analysis showed m/e = 407 (M + H+).