The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 29, 1986
Filed:
May. 21, 1984
Rudolf Franzmair, Linz, AT;
Chemie Linz Aktiengesellschaft, Linz, AT;
Abstract
The invention relates to a process for the preparation of .beta.-methyldigoxin by the selective methylation of digoxin with dimethyl sulfate in the presence of a basic strontium compound and, if appropriate, of an inert inorganic adsorbent. Strontium hydroxide octahydrate, strontium methylate or strontium hydroxymethylate is used as the basic strontium compound, and an oxide, silicate or phosphate of magnesium, calcium, aluminum, silicon or titanium, with a water content in the range of 0 to 20% by weight, is used as the inorganic adsorbent. The reaction is carried out at temperatures of -15.degree. to 15.degree. C. in the presence of 3 to 24 moles of water per mole of digoxin, the water being introduced in the reaction mixture by the water content of strontium hydroxide octahydrate and/or the inorganic adsorbent used and purification of the methylation product so formed by column chromatography on SiO.sub.2 with a mixture of chlorohydrocarbon and a lower aliphatic alcohol.