Preparation of astaxanthin, novel intermediates therefor and the preparation thereof

US5625099A · kind A · utility

Inventors

• Hansgeorg Ernst · Speyer, DE
• Walter Dobler · Schwetzingen, DE
• Joachim Paust · Schifferstadt, DE
• Udo Rheude · Otterstadt, DE

Key dates

• Filing date: May 23, 1995
• Grant date: Apr 29, 1997
• Expiry date: May 23, 2015

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P20/55
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Abstract of the Disclosure: Compounds of the formula I ##STR1## where R.sup.1 is H or C.sub.1 -C.sub.4 -alkyl, R.sup.2 is C.sub.1 -C.sub.4 -alkyl and R.sup.3 is an ether, silyl ether or acetal protective group which can be converted into a hydroxyl group by hydrolysis, in particular one of the radicals ##STR2## and a process for preparing these compounds by reacting an alkenyne of the formula II ##STR3## in an inert solvent in the presence of lithium amide with a cyclohexenone of the formula III ##STR4## and the use of the compounds of the formula I for preparing astaxanthin, are described.