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:
May. 17, 1983
Filed:
Jan. 19, 1982
Maurice Grelat, Bettingen, CH;
Ciba-Geigy Corporation, Ardsley, NY (US);
Abstract
The present invention relates to an advantageous novel process for producing 1-acylamino-3,4-phthaloylacridones by a hydrogenating ring-closure reaction of 1-acylamino-4-anilidoanthraquinone-2'-carboxylic acid esters. The ring-closure reaction according to the invention to the acridone ring is performed under mild conditions, with regard to temperature and alkalinity of the reaction medium, with the use of a hydrogenating catalyst. The first step to effect the ester formation can be carried out, as a single-vessel reaction, with the use of a polar solvent as the reaction medium, and of an alkylphosphoric acid dialkyl ester as the esterifying agent.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile