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:
Aug. 07, 1984
Filed:
Sep. 28, 1982
Csaba Szantay, Budapest, HU;
Lajos Szabo, Budapest, HU;
Gyorgy Kalaus, Budapest, HU;
Janos Kreidl, Budapest, HU;
Andras Nemes, Budapest, HU;
Maria Farkas nee Kirjak, Budapest, HU;
Gyorgy Visky, Budapest, HU;
Laszlo Czibula, Budapest, HU;
Richter Gedeon Vegyeszeti Gyar Rt., Budapest, HU;
Abstract
The invention relates to a new process for the preparation of apovincaminic acid esters. More particularly, the invention concerns a process for preparing racemic and optionally active vincaminic acid esters of the formula (I) ##STR1## in which R.sup.1 and R.sup.2 independently stand for alkyl having from one to 6 carbon atoms, and 14-epimers thereof. According to the invention an octahydroindolo[2,3-a]quinolizine-oxime ester of the formula (II) ##STR2## in which R.sup.1 and R.sup.2 have the same meaning as defined above, is reacted with an aqueous solution of sulfurous acid or a salt thereof at a temperature of 80.degree. to 110.degree. C. and the 14-epimeric mixture obtained is epimerized or separated in a known manner and if desired, the racemic vincaminic acid esters are resolved. The valuable, pharmaceutically active compounds of the formula (I) can be prepared according to the invention in a considerably improved yield and the undesired side reactions can be suppressed and/or the by-products can easily be converted into other pharmaceutically active materials.