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:
Nov. 16, 1999
Filed:
Jul. 31, 1997
Guido Di Napoli, Collonge-Bellerive, CH;
Laboratoire Medidom S.A., Geneve, CH;
Abstract
The following description sets forth a process for producing rhein, diacerhein and other diacyl derivatives thereof, which comprises the following steps: treatment of a diphenylketone ##STR1## in which R.sub.1 is --OR', --NR'R', --SR', where R' and R' are H, an alkyl or aromatic group; R.sub.2 is H or a protective group, R.sub.3 is --OH or C.sub.1 -C.sub.4 alkyl, with an acid or superacid to give a 1-aminoanthraquinone derivative, diazotisation, replacement of the --NH.sub.2 group by --OH, optional removal of the protective group, and acylation.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile