936359-29-4Relevant academic research and scientific papers
Process for the purification of montelukast
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Page/Page column 7, (2008/06/13)
It relates to a process for the purification of Montelukast, or pharmaceutically salts thereof, or solvates thereof, including stereoisomers or mixture thereof which comprises carrying out a specific set of selective solvent extractions of Montelukast or its impurities in a mixture of an organic solvent and water at specific ranges of pH and temperature which depend on the type of impurities to remove. In particular, it comprises at least one wash of an aqueous phase containing crude Montelukast in salt form with an organic solvent, at a pH comprised between 12.0 and 13.5; and optionally one or more washes of the resulting aqueous phase with an organic solvent at a pH comprised between 8.5 and 10.0. Montelukast is recovered by acidification at a pH comprised between 4.5 and 8.0 and solvent extraction, and is isolated either as acid or in salt form.
Process for the preparation of a leukotriene antagonist and intermediates thereof
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Page/Page column 9, (2008/06/13)
It comprises a preparation process of Montelukast from an intermediate compound of formula (V), which is previously prepared by reaction of the corresponding sulfonate with 1-(mercaptomethyl)cyclopropyl)methanol. Compound (V) is reacted with a Grignard reactant to convert the ester group into a tertiary alcohol, followed by conversion of the primary alcohol into a sulfonate, substitution of the sulfonate group by a cyano group, and finally transforming the cyano compound to the carboxilic acid compound by a hydrolysis reaction to afford Montelukast. Montelukast can also be prepared by a hydrolysis reaction of the corresponding amide. It also comprises intermediate compounds useful in such preparation process.
