New process for preparing cis-3,3,5-trimethylcyclohexyl-D,L-alpha-(3-pyridinecarboxy)-phenylacetate

摘要

A process for producing cis-3,3,5-trimethylcyclohexyl-D,L-a-(3-pyridinecarboxy)-phenylacetate (I) for use in human therapy as a spasmolytic and vasodilator.;By means of a first series of reactions and starting from pyridine-3-carboxylic acid (II), the hydrochloride of D,L-a-(3-pyridinecarboxy)-phenylacetic acid (VIII) is produced in crystalline form at high purity, from which by treatment with cis-3,3,5-trimethylcyclohexanol (IX) in a medium consisting of chloromethylene dimethylammonium chloride in methylene chloride, the product (I) is obtained in a form which is easily purified by treatment with p.toluenesulphonic acid followed by treatment with an alkaline base.