abstract |
The invention relates to a preparation method of high-purity fexofenadine (chemical name (+/-)-4-[1-hydroxyl-4-[4-(hydroxyldiphenylmethyl)-1-piperidyl]butyl]-alpha, alpha-dimethylphenylacetic acid) and an intermediate thereof and a novel synthesizing route. The method comprises the following steps of: with p-cyanomethylbenzoate (II) as a raw material, and with a new compound (Va) or salt (Vb) thereof as a key intermediate, hydrolyzing, esterifying or halogenating to obtain a compound (VII); and condensing, hydrolyzing and reducing with a piperdinol compound (VIII) to obtain a high-purity fexofenadine type compound (I) without para-position substitution. The invention has the advantages of simple reaction, convenience for postprocessing, higher yield and high purity of generated products and is a more ideal preparation method of fexofenadine. |