合成路线图解说明: Condensation of 4-chromanone (I) with diethyl oxalate in the presence of sodium hexamethyldisilazane in THF at low temperature gave diketone (II), which on cyclization with hydrazine hydrochloride in refluxing ethanol provided pyrazole (III). Reduction of the ester group with LiAlH4 in THF yielded alcohol (IV). This was converted into chloride (V) by reaction with the complex between oxalyl chloride and dimethylformamide. Finally, alkylation of 1-(4-methoxyphenyl)piperazine (VI) with this chloride furnished the title compound. |