申请人:HOECHST MARION ROUSSEL, INC.
公开号:EP0415384A2
公开(公告)日:1991-03-06
An amino-acid ester compound can be cyclized into a cyclic amido-carbonyl compound by contacting the amino-acid ester compound in a liquid medium with a heterogeneous acidic ion-exchange substance. For example, 2-hydroxy-3-(2-aminophenylthio)-3-(4-methoxyphenyl)propionic acid, methyl ester, threo form, can be cyclized in an aqueous mixture into cis-2-(4-methoxyphenyl)-3-hydroxy-2,3-dihydro-1,5-benzothiazepin-4(5H)-one by employing a sulfonated polystyrene-divinylbenzene ion-exchange resin in its acid form, e.g., Dowex 50X4-400, at yields exceeding 85 percent of theory, and the product can be used to make diltiazem hydrochloride.
通过将氨基酸酯化合物在液体介质中与异质酸性离子交换物质接触,可将氨基酸酯化合物环化为环状氨基羰基化合物。例如,2-羟基-3-(2-氨基苯硫基)-3-(4-甲氧基苯基)丙酸甲酯,苏氨酸形式,可以通过使用磺化聚苯乙烯-二乙烯基苯离子交换树脂的酸性形式,在水性混合物中环化成顺式-2-(4-甲氧基苯基)-3-羟基-2,3-二氢-1,5-苯并硫氮杂卓-4(5H)-酮、Dowex 50X4-400,产量超过理论值的 85%,产品可用于制造盐酸地尔硫卓。