472-70-8Relevant academic research and scientific papers
Bidirectional Hiyama–Denmark Cross-Coupling Reactions of Bissilyldeca-1,3,5,7,9-pentaenes for the Synthesis of Symmetrical and Non-Symmetrical Carotenoids
Rivas, Aurea,Pérez-Revenga, Víctor,Alvarez, Rosana,de Lera, Angel R.
, p. 14399 - 14407 (2019/11/03)
The construction of the carotenoid skeleton by Pd-catalyzed Csp2?Csp2 cross-coupling reactions of symmetrical and non-symmetrical 1,10-bissilyldeca-1,3,5,7,9-pentaenes and the corresponding complementary alkenyl iodides has been developed. Reaction conditions for these bidirectional and orthogonal Hiyama–Denmark cross-coupling reactions of bisfunctionalized pentaenes are mild and the carotenoid products preserve the stereochemical information of the corresponding oligoene partners. The carotenoids synthesized in this manner include β,β-carotene and (3R,3′R)-zeaxanthin (symmetrical) as well as 9-cis-β,β-carotene, 7,8-dihydro-β,β-carotene and β-cryptoxanthin (non-symmetrical).
Process or synthesis of (3S)- and (3R)-3-hydroxy-beta-ionone, and their transformation to zeaxanthin and beta-cryptoxanthin
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, (2012/07/27)
Disclosed is 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-hydrox-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 commercial available 2,5- dimethtylocta-2,4,6-triene-1,8-dial provided all 3 stereoisomers of zeaxanthin. Similarly, (3R)-C15-Wittig and its (3S)-enantiomer were each coupled with β-apo-12′-carotenal.
Synthesis of (3S)- and (3R)-3-hydroxy-β-ionone and their transformation into (3S)- and (3R)-β- cryptoxanthin
Khachik, Frederick,Chang, An-Ni
, p. 509 - 516 (2011/04/16)
(3S)- and (3R)-3-Hydroxy-β-ionone and (3S)- and (3R)-3-Hydroxy-β- ionone synthesized in high enantiomeric purity from commercially available () - ionone. These ionones were then transformed into (3R) - cryptoxanthin and (3S) - cryptoxanthin by a C15+C10+C15 Wittig coupling strategy according to known methods. This methodology can considerably simplify the total synthesis of optically active carotenoids with 3-hydroxy - end groups that possess significant biological activities. Georg Thieme Verlag Stuttgart New York.
Process For The Preparation of Beta and Alpha Cryptoxanthin
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Page/Page column title page; 3; 7; 11-12, (2010/12/29)
The present invention relates to a process for converting lutein and/or lutein esters to (3R)-β-cryptoxanthin and (3R,6′R)-α-cryptoxanthin, suitable for human consumption as dietary supplements, by employing safe and environmentally friendly reagents. (3R)-β-Cryptoxanthin and (3R,6′R)-α-cryptoxanthin are two rare food carotenoids that are not commercially available and the former exhibits vitamin A activity. In the first synthetic step, commercially available lutein and/or lutein esters are transformed into a mixture of dehydration products of lutein (anhydroluteins) in the presence of a catalytic amount of an acid. The resulting anhydroluteins are then converted to (3R)-β-cryptoxanthin (major product) and (3R,6′R)-α-cryptoxanthin (minor product) by heterogeneous catalytic hydrogenation employing transition elements of group VIII (Pt, Pd, Rh supported on alumina or carbon) in a variety of organic solvents under atmospheric pressure of hydrogen and at temperatures ranging from ?15° C. to 40° C. Among these catalysts, Pt supported on alumina at 40° C. in ethyl acetate provides the best yield of (3R)-β-cryptoxanthin and (3R,6′R)-α-cryptoxanthin. Several homogeneous catalysts can also promote the regioselective hydrogenation of anhydroluteins to a mixture of (3R)-β-cryptoxanthin and (3R,6′R)-α-cryptoxanthin in low to moderate yields. The catalysts may be transition metal complexes such as palladium acetylacetonate, Rh(Ph3P)3Cl (Wilkinson's catalyst), [(C6H11)3P[C8H12][C5H5N] Ir+PF6? (Crabtree catalyst), or [C8H12][(MePh2P)2]Ir+PF6?. Among these, Wilkinson catalyst converts anhydroluteins to (3R)-β-cryptoxanthin and (3R,6′R)-α-cryptoxanthin in nearly quantitative yield. A novel feature of this invention is the regioselective hydrogenation of anhydroluteins while the highly conjugated polyene chain of these carotenoids remains intact.
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.
ISOLATION AND PURIFICATION OF CAROTENOIDS FROM MARIGOLD FLOWERS
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Page/Page column 10-12, (2008/06/13)
The present invention explains a realistic and effective process for isolating and purifying carotenoids containing higher concentrations of carotenoids such as trans-lutein, trans-zeaxanthin, Cis-lutein, ?-carotene and Cryptoxanthin from Marigold flower petals under controlled conditions leaving no traces of any organic hazardous solvents. The process involves ensilaging marigold flowers, dehydration, solvent extraction, alkali hydrolysis of carotenoid esters with absolute alcohol, crystallization/purification using water, absolute alcohol mixture followed by filteration and drying until the crystals are considerably free from moisture and absolutely free from residual hazardous solvents. These crystals are suitable for nutraceutical and food products as supplements.
PROCESS FOR THE PREPARATION OF ALPHA- AND BETA-CRYPTOXANTHIN
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Page/Page column 14-20; 26-28, (2008/06/13)
The present invention relates to a process for converting lutein and/or lutein esters to β-cryptoxanthin and α-cryptoxanthin, suitable for human consumption as dietary supplements, by employing safe and environmentally friendly reagents. In the first synthetic step, commercially available lutein and/or lutein esters are transformed into a mixture of dehydration products of lutein (anhydroluteins) in the presence of a catalytic amount of an acid. The resulting anhydroluteins are then converted to β-cryptoxanthin (major product) and α-cryptoxanthin (minor product) by heterogeneous catalytic hydrogenation employing transition elements of group VIII in a variety of organic solvents under atmospheric pressure of hydrogen. A novel feature of this invention is the regioselective hydrogenation of anhydroluteins while the highly conjugated polyene chain of these carotenoids remains intact.
Coenzyme Q10 formulation and process methodology for soft gel capsules manufacturing
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, (2008/06/13)
A formulation of Coenzyme Q10, beta-carotenes, Vitamin E, and medium chain triglycerides in rice bran oil and an optional thickener, such as bee's wax, is provided in a soft gel capsule so that a maximum of the Coenzyme Q10is absorbed by the human body. Generally, about 60 mg of Coenzyme Q10is the normal amount provided daily to a healthy sedentary adult.
Method for production of rare carotenoids from commercially available lutein
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Page/Page column 11-12, (2008/06/13)
Disclosed are processes for conversion of (3R,3′R,6′R)-lutein to (3R,6′R)-α-cryptoxanthin, (3R)-β-cryptoxanthin, anhydroluteins I, II, and III (dehydration products of lutein), and a method for separating and purifying the individual carotenoids including the unreacted (3R,3′R)-zeaxanthin. The invention also includes two methods that transform (3R,3′R,6′R)-lutein into (3R,6′R)-α-cryptoxanthin in excellent yields.
Isomerizing cis-carotenoids to all-trans-carotenoids
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, (2008/06/13)
Cis-isomers of a carotenoid are isomerized to an all-trans-isomer of the carotenoid by heating the cis-isomers in water at above about 50° C.
