ISSN:
0018-019X
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Technical Procedures for the Synthesis of Carotenoids and Related Compounds from 6-Oxo-isophorone. I. Modification of the Kienzle-Mayer-Synthesis of (3S, 3′S)-AstaxanthinAn efficient synthesis of (3S, 3′S)-astaxanthin (1a) in high yield and optical purity starting from (4R, 6R)-4-hydroxy-2,2,6-trimethylcyclohexanone (4) is reported. The absolute configuration of 1a, previously derived from ORD. data, has been confirmed by X-ray analysis of 5, a derivative of 6-oxo-isophorone (2). The key features of the improved synthesis are the two-step conversion of 4 to the key intermediate (4S)-2,6,6-trimethyl-4-hydroxy-2-cyclohexen-1-one (14), a new method for the partial reduction of the sterically hindered triple bond of (S)-6-hydroxy-3-(5-hydroxy-3-methyl-3-penten-1-ynyl)-2,4,4-trimethyl-2-cyclohexen-1-one (32), and Wittig olefination of the dialdehyde 1,6-dimethyl-1,3,5-octatrienedial (38) using phosphonium salt 37 with a free hydroxyl group.
Additional Material:
2 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/hlca.19810640749
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