15647-89-9Relevant articles and documents
Reaction of R-pulegone with P–H phosphonium salts
Fayzullin, Robert R.,Grigor'eva, Leysan R.,Khasiyatullina, Nadezhda R.,Mironov, Vladimir F.,Nemtarev, Andrey V.,Shemakhina, Mariya E.
, p. 700 - 702 (2021/01/12)
The reaction of the R-pulegone with P–H-phosphonium salts gives the corresponding 8-phosphonio-p-menthan-3-one salts with high regio- and stereoselectivity. The structure of salts was determined by NMR and IR spectroscopy, mass spectrometry and X-ray diffraction analysis.
Process for Synthesis of (3S)- and (3R)-3-Hydroxy-Beta-Ionone, and Their Transformation to Zeaxanthin and Beta-Cryptoxanthin
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, (2009/12/27)
(3R)-3-Hydroxy-β-ionone and (3S)-3-hydroxy-β-ionone are two important intermediates in the synthesis of carotenoids with β-end group such as lutein, zeaxanthin, β-cryptoxanthin, and their stereoisomers. Among the various stereoisomers of these carotenoids, only (3R,3′R,6′R)-lutein, (3R,3′R)-zeaxanthin, and (3R)-β-cryptoxanthin are present in commonly consumed fruits and vegetables. There are 3 possible stereoisomers for zeaxanthin, these are: dietary (3R,3′R)-zeaxanthin (1), non-dietary (3S,3′S)-zeaxanthin (2), and non-dietary (3R,3′S;meso)-zeaxanthin (3) which is a presumed metabolite of dietary lutein. Dietary lutein as well as 1 and 3 are accumulated in the human macula and have been implicated in the prevention of age-related macular degeneration. (3R)-β-Cryptoxanthin (4) is also present in selected ocular tissues at a very low concentration whereas its enantiomer (3S)-β-cryptoxanthin (5) is absent in foods and human plasma. The present invention relates to a process for the synthesis of (3R)-3-hydroxy-β-ionone and its (3S)-enantiomer in high optical purity from commercially available (rac)-α-ionone. The key intermediate for the synthesis of these hydroxyionones is 3-keto-α-ionone ketal that was prepared from (rac)-α-ionone after protection of this ketone as a 1,3-dioxolane. Reduction of 3-keto-α-ionone ketal followed by deprotection, lead to 3-hydroxy-α-ionone that was transformed into (rac)-3-hydroxy-β-ionone by base-catalyzed double bond isomerization in 46% overall yield from (rac)-α-ionone. The racemic mixture of these hydroxyionones was then resolved by enzyme-mediated acylation in 96% ee. (3R)-3-Hydroxy-β-ionone and its (3S)-enantiomer were respectively transformed to (3R)-3-hydroxy-(β-ionylideneethyl)triphenylphosphonium chloride [(3R)—C15-Wittig salt] and its (3S)-enantiomer [(3S)—C15-Wittig salt] according to known procedures. Double Wittig condensation of these Wittig salts with commercially available 2,5-dimethylocta-2,4,6-triene-1,8-dial provided all 3 stereoisomers of zeaxanthin (1-3). Similarly, (3R)—C15-Wittig and its (3S)-enantiomer were each coupled with β-apo-12′-carotenal to yield 4 and 5.
Tocopherols, tocotrienols, other chroman and side chain derivatives and uses thereof
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, (2008/06/13)
The present invention provides an antiproliferative compound having a structural formula where X and Y independently are oxygen, nitrogen or sulfur; R1 is alkyl, alkenyl, alkynyl, aryl, heteroaryl, carboxylic acid, carboxylate, carboxamide, est
