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:
Jan. 20, 1998
Filed:
Dec. 21, 1995
Alfons Carcasona, Koln, DE;
Wolf Grimminger, Bergisch-Gladbach, DE;
Pentti Hietala, Helsinki, FI;
Helga Zaeske, Overath, DE;
Klaus Witthohn, Overath, DE;
Madaus AG, Cologne, DE;
Abstract
Sennosides A, B and Al of the formula: ##STR1## which are substantially free from sennosides C, D and Dl, and from aloe-emodin derivatives, are prepared by a process wherein a) a sennoside mixture is reduced to rhein-9-anthrone-8-glucoside and aloe-emodin-9-anthrone-8-glucoside, b) a liquid-liquid partitioning of the compounds obtained is carried out between a polar organic solvent which is only partly miscible with water and an aqueous phase and c) the rhein-9-anthrone-8-glycosides contained after the partitioning in the aqueous phase is again oxidized to the corresponding sennosides and these are recovered.