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Baicalin in radical scavenging and its synergistic effect with β-carotene in antilipoxidation
The lipophilic flavonoid glycoside baicalin from the traditional oriental herb Scutellaria baicalensis Georgi (logP=1.27, pKa1=7.6, pK a2=10.1 as determined at 25 °C in 0.1 M NaCl) is found to be as reducing (0.39 V vs NHE, reversibl
Liang,Rui-Min,Li-Min,Xi-Cheng,Zhang, Jian-Ping,Skibsted, Leif H.
p. 7118 - 7124
(2009)
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Preparation method of β - carotene with high total trans content
The invention provides a preparation method of β - carotene with a high total trans content. Starting from the vitamin A derivative, C20 phosphine salt is obtained through reaction with triphenylphosphine, and the C20 phosphine salt is subjected to condensation reaction under the action IBX high iodine compound and base to obtain β - carotene containing cis-trans, and then the β - carotene with high trans content is obtained under the action of a transition metal loading catalyst. The method avoids the use of a strong oxidizing agent in the traditional process, is environmentally friendly and can reduce the peroxidation of β - carotene, so that the reaction yield is increased, and the transition metal catalyst enables the obtained β - carotene content to be full. Trans increase.
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Paragraph 0063; 0065; 0085-0086

(2021/09/01)

Method for preparing beta-carotene
The invention relates to a compound prepartion field, particularly relates to a method for preparing beta-carotene. The method comprises the following steps: carrying out oxidative coupling reaction between the vitamin A organic phosphine saltin formula (
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Paragraph 0053-0056

(2021/02/04)

Construction of new cucumber fruit mottle mosaic virus derived subgenomic promotor and expression vector, and use thereof
The purpose of the present invention is to develop a cucumber fruit mottle mosaic virus vector so as to enable a study of gene function through gene silencing phenomenon in Cucurbitaceae plants, which has been difficult to study in the past, and to enable the study in fruits as well through stable expression. Furthermore, the present invention establishes a system that enables expression of a heterologous protein in plants, thereby, for the first time, providing a vector applicable to both the gene silencing phenomenon and protein expression in Cucurbtaceae plants.
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(2019/01/20)

Bidirectional Hiyama–Denmark Cross-Coupling Reactions of Bissilyldeca-1,3,5,7,9-pentaenes for the Synthesis of Symmetrical and Non-Symmetrical Carotenoids
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).
Rivas, Aurea,Pérez-Revenga, Víctor,Alvarez, Rosana,de Lera, Angel R.
p. 14399 - 14407
(2019/11/03)

Synthesis of apocarotenoids by acyclic cross metathesis and characterization as substrates for human retinaldehyde dehydrogenases
A new synthesis of three apocarotenoids, namely 14′-apo-β-carotenal, 12′-apo-β-carotenal and 10′-apo-β-carotenal, has been achieved that is based on the acyclic cross-metathesis of the hexaene derived from retinal and the corresponding partners. These compounds can be enzymatically converted to their carboxylic acids by the human aldehyde dehydrogenases involved in retinaldehyde oxidation. Their kinetic parameters suggest that these enzymes might play a role in the physiological metabolism of apocarotenoids.
Domínguez, Marta,Pequerul, Raquel,Alvarez, Rosana,Giménez-Dejoz, Joan,Birta, Eszter,Porté, Sergio,Rühl, Ralph,Parés, Xavier,Farrés, Jaume,de Lera, Angel R.
p. 2567 - 2574
(2018/04/19)

Method for preparing all-trans-beta-carotene
The invention provides a method for preparing all-trans-beta-carotene. According to the method for preparing the all-trans-beta-carotene, an alkaline ionic liquid provides a strong alkaline environment, so that 2,4-pentadiene pentadecarbonate and 2,7-dime
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Paragraph 0065-0067; 0069-0072; 0075-0114

(2018/11/22)

Synthetic method for beta-carotene
The invention provides a synthetic method for beta-carotene. The synthetic method comprises the following steps: preparing an organic phosphine salt from retinol or a derivative thereof; and subjecting the organic phosphine salt to an intermolecular oxida
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Paragraph 0046; 0048; 0056; 0057

(2018/11/27)

PRECURSOR COMPOUNDS FOR PROVIDING RETINOIDS OF THE VITAMIN A5 PATHWAY AND USES THEREOF
The invention relates to the field of retinoid X receptor (RXR) signalling and a novel vitamin A pathway called Vitamin A5 pathway. Compounds which are useful to provide (R) 9-cis-13,14-dihydro-retinoic acid an endogenous RXR ligand are claimed as well as their uses and method for preparation thereof. The compounds of the invention are useful for pharmaceutical and nutritional uses.
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(2018/06/06)

Kaempferol Binding to Zinc(II), Efficient Radical Scavenging through Increased Phenol Acidity
Zinc(II) enhances radical scavenging of the flavonoid kaempferol (Kaem) most significantly for the 1:1 Zn(II)-Kaem complex in equilibrium with the 1:2 Zn(II)-Kaem complex both with high affinity at 3-hydroxyl and 4-carboxyl coordination. In methanol/chloroform (7/3, v/v), 1:1 Zn(II)-Kaem complex reduces β-carotene radical cation, β-Car?+, with a second-order rate constant, 1.88 × 108 L·mol-1·s-1, while both Kaem and 1:2 Zn(II)-Kaem complex are nonreactive, as determined by laser flash photolysis. In ethanol, 1:1 Zn(II)-Kaem complex reduces the 2,2-diphenyl-1-picrylhydrazyl radical, DPPH?, with a second-order rate constant, 2.48 × 104 L·mol-1·s-1, 16 times and 2 times as efficient as Kaem and 1:2 Zn(II)-Kaem complex, respectively, as determined by stopped-flow spectroscopy. Density functional theory calculation results indicate significantly increased acidity of Kaem as ligand in 1:1 Zn(II)-Kaem complex other than in 1:2 Zn(II)-Kaem complex. Kaem in 1:1 Zn(II)-Kaem complex loses two protons (one from 3-hydroxyl and one from phenolic hydroxyl) forming 1:1 Zn(II)-(Kaem-2H) during binding with Zn(II), while Kaem in 1:2 Zn(II)-Kaem complex loses one proton in each ligand forming Zn(II)-(Kaem-H)2, as confirmed by UV-vis absorption spectroscopy. Zn(II)-(Kaem-2H) is a far stronger reductant than Kaem and Zn(II)-(Kaem-H)2 as determined by cyclic voltammetry. Significant rate increases for the 1:1 complex in both β-Car?+ scavenging by electron transfer and DPPH? scavenging by hydrogen atom transfer were ascribed to decreases of ionization potential and of bond dissociation energy of 4′-OH for deprotonated Zn(II)-(Kaem-2H), respectively. Increased phenol acidity of plant polyphenols by 1:1 coordination with Zn(II) may explain the unique function of Zn(II) as a biological antioxidant and may help to design nontoxic metal-based drugs derived from natural bioactive molecules.
Xu, Yi,Qian, Ling-Ling,Yang, Jing,Han, Rui-Min,Zhang, Jian-Ping,Skibsted, Leif H.
p. 10108 - 10117
(2018/12/01)

METHOD FOR PRODUCING PULVERIZED ORGANIC COMPOUND PARTICLE
Disclosed is a method for producing pulverized particles of a crystalline organic compound which is poorly water-soluble. Also disclosed is a pulverized organic compound particle produced by such a method. Specifically disclosed is a method for producing a poorly water-soluble organic compound particle for medical use, which is characterized in that a poorly water-soluble organic compound for medical use is mixed with a physiologically acceptable salt and a physiologically acceptable polyol, and subjected to wet milling. Also specifically disclosed is a poorly water-soluble organic compound particle for medical use, which is produced by such a production method.
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(2015/12/19)

AN IMPROVED PROCESS FOR THE PREPARATION OF β-CAROTENE
The present invention relates to an improved process for the preparation of β-carotene having pharmaceutically acceptable level of residual solvent content.
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Page/Page column 11; 12

(2015/07/15)

A conjunctive diiodoheptaene for the synthesis of C2-symmetric carotenoids
(2E,4E,6E,8E,10E,12E,14E)-2,15-Diiodo-6,11-dimethylhexadeca-2,4,6,8,10,12, 14-heptaene, prepared by homometathesis, has been used in palladium-catalyzed Suzuki and Stille cross-coupling reactions with the appropriate partners to construct the C2-symmetric carotenoids β,β-carotene, lycopene, synechoxanthin and 4,4′-diapo-ψ,ψ-carotene-4,4′- dial. The Royal Society of Chemistry 2013.
Fontán, Noelia,Vaz, Belén,álvarez, Rosana,De Lera, ángel R.
supporting information
p. 2694 - 2696
(2013/04/10)

Reductive coupling of aldehydes by H2S in aqueous solutions, a C-C bond forming reaction of prebiotic interest
We report here a novel reductive coupling reaction of conjugated, non- or poorly enolizable aldehydes induced by H2S and operative in aqueous solutions under prebiotically relevant conditions. This reaction leads from retinal to β-carotene, and from benzylic aldehydes to the corresponding diarylethylenes. This novel reaction also opens a new potentially prebiotic pathway leading from glyoxylic acid to various compounds that are involved in the reductive tricarboxylic acid cycle. This C-C bond forming reaction of prebiotic interest might have been operative, notably, in the sulfide-rich environments of hydrothermal vents, which have been postulated as possible sites for the first steps of organic chemical evolution.
Kajjout, Mohammed,Hebting, Yanek,Albrecht, Pierre,Adam, Pierre
experimental part
p. 714 - 726
(2012/07/14)

Plant carotene cis-trans isomerase CRTISO: A new member of the FAD red-dependent flavoproteins catalyzing non-redox reactions
The carotene cis-trans isomerase CRTISO is a constituent of the carotene desaturation pathway as evolved in cyanobacteria and prevailing in plants, in which a tetra-cis-lycopene species, termed prolycopene, is formed. CRTISO, an evolutionary descendant of the bacterial carotene desaturase CRTI, catalyzes the cis-to-trans isomerization reactions leading to all-trans-lycopene, the substrate for the subsequent lycopene cyclization to form all-trans-α/ β-carotene. CRTISO and CRTI share a dinucleotide binding motif at the N terminus. Here we report that this site is occupied by FAD in CRTISO. The reduced form of this cofactor catalyzes a reaction not involving net redox changes. Results obtained with C(1)- and C(5)-deaza-FAD suggest mechanistic similarities with type II isopentenyl diphosphate: dimethylallyl diphosphate isomerase (IDI-2). CRTISO, together with lycopene cyclase CRTY and IDI-2, thus represents the third enzyme in isoprenoid metabolism belonging to the class of non-redox enzymes depending on reduced flavin for activity. The regional specificity and the kinetics of the isomerization reaction were investigated in vitro using purified enzyme and biphasic liposome-based systems carrying specific cis-configured lycopene species as substrates.Thereaction proceeded from cis to trans, recognizing half-sides of the symmetrical prolycopene and was accompanied by one trans-to-cis isomerization step specific for the C(5)-C(6) double bond. Rice lycopene β-cyclase (OsLCY-b), when additionally introduced into the biphasic in vitro system used, was found to be stereospecific for all-trans-lycopene and allowed the CRTISO reaction to proceed toward completion by modifying the thermodynamics of the overall reaction.
Yu, Qiuju,Ghisla, Sandro,Hirschberg, Joseph,Mann, Varda,Beyer, Peter
experimental part
p. 8666 - 8676
(2012/03/08)

Synthesis of C40-symmetrical fully conjugated carotenoids by olefin metathesis
In an effort to push olefin metathesis to the limits of conjugation in reactants and products, the C40-symmetrical carotenoids β,β-carotene (1), lycopene (2), (3R,3′R)-zeaxanthin (3), and rac-isozeaxanthin (4), which are conjugated undecaenes, have been synthesized from C21-terminal hexaenes by treatment with Grubbs' second-generation Ru catalyst in dichloromethane at 50 °C.
Fontan, Noelia,Dominguez, Marta,Ulvarez, Rosana,De Lera, Ungel R.
p. 6704 - 6712
(2012/01/03)

Artificially coloring the skin with a carotene compound, a xanthophyll compound and a lipophilic green dye composition
A method for artificially coloring the skin entails topical application thereon of a composition containing, formulated into a physiologically acceptable medium: a) at least one compound of the carotene type,b) at least one compound of the xanthophyll type,c) at least one lipophilic green dye; the composition advantageously includes a mixture of dyes including:a) at least one compound of the carotene type,b) at least astaxanthin,c) at least one lipophilic green dye.
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(2010/06/22)

Fast regeneration of carotenoids from radical cations by isoflavonoid dianions: Importance of the carotenoid keto group for electron transfer
Electron transfer to radical cations of β-carotene, zeaxanthin, canthaxanthin, and astaxanthin from each of the three acid/base forms of the diphenolic isoflavonoid daidzein and its C-glycoside puerarin, as studied by laser flash photolysis in homogeneous methanol/chloroform (1/9) solution, was found to depend on carotenoid structures and more significantly on the deprotonation degree of the isoflavonoids. None of the carotenoid radical cations reacted with the neutral forms of the isoflavonoids while the monoanionic and dianionic forms of the isoflavonoids regenerated the oxidized carotenoid. Electron transfer to the β-carotene radical cation from the puerarin dianion followed second order kinetics with the rate constant at 25 °C k2 = 5.5 × 109 M-1 s-1, zeaxanthin 8.5 × 109 M-1 s-1, canthaxanthin 6.5 × 1010 M-1 s-1, and astaxanthin 11.1 × 1010 M-1 s-1 approaching the diffusion limit and establishing a linear free energy relationship between rate constants and driving force. Comparable results found for the daidzein dianion indicate that the steric hindrance from the glucoside is not important suggesting the more reducing but less acidic 4′-OH/4′-O- as electron donors. On the basis of the rate constants obtained from kinetic analyses, the keto group of carotenoids is concluded to facilitate electron transfer. The driving force was estimated from oxidation potentials, as determined by cyclic-voltametry for puerarin and daidzein in aqueous solutions at varying pH conditions, which led to the standard reduction potentials E° = 1.13 and 1.10 V versus NHE corresponding to the uncharged puerarin and daidzein. For pH > pka2, the apparent potentials of both puerarin and daidzein became constants and were E° = 0.69 and 0.65 V, respectively. Electron transfer from isoflavonoids to the carotenoid radical cation, as formed during oxidative stress, is faster for astaxanthin than for the other carotenoids, which may relate to astaxanthins more effective antioxidative properties and in agreement with the highest electron accepting index of astaxanthin.
Han, Rui-Min,Chen, Chang-Hui,Tian, Yu-Xi,Zhang, Jian-Ping,Skibsted, Leif H.
scheme or table
p. 126 - 132
(2010/05/11)

Dialdehyde compound, preparation method thereof, and synthetic method of carotenoids using the same
The novel C dialdehyde compound which can be efficiently utilized in the synthesis of carotenoid compounds based on the sulfone chemistry, the preparation method of the same, and the expeditious and practical synthetic processes for lycopene and β-carotene by the use of the above novel compound are disclosed. The syntheses of lycopene and β-carotene are characterized by the processes of the coupling reaction between two equivalents of geranyl sulfone or cyclic geranyl sulfone and the above C dialdehyde, the functional group transformation reactions of the diol in the resulting C 40 coupling products to X's (either halogens or ethers), and the double elimination reactions of the functional groups of the benzenesulfonyl and X to produce the fully conjugated polyene chain of the carotenoids.
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Page/Page column 12

(2009/12/28)

C10 Dialdehyde, Synthetic Method Thereof, and Synthetic Method of Beta-Carotene Using the Same
The novel intermediate compound which can be efficiently utilized in the synthesis of carotenoid compounds based on the sulfone chemistry, the preparation method of the same, and the practical synthetic process for preparing β-carotene by the use of the above novel compound are disclosed. The synthesis of β-carotene is characterized by the double elimination reactions of the C40 compound containing both the benzenesulfonyl group and the group X (either halogen or ether), which can be prepared by the coupling reaction of the novel C10 dialdehyde with two equivalents of the C15 allylic sulfone, followed by the functional group transformation of the resulting C40 diol either to the corresponding halide or to the ether, to produce the fully conjugated polyene chain.
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Page/Page column 8

(2008/12/04)

PROCESS FOR EXTRACTION OF CAROTENOIDS
The presente invention is related to new techniques for the extraction of carotenoids, preferably beta-carotene, from solid residues or husks coming from the processing of palms. This technique is based on the use of organic and inorganic solvents such as carbon dioxide (CO2) and/or light hydrocarbons.
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Page/Page column 4-6

(2008/06/13)

New syntheses of retinal and its acyclic analog γ-retinal by an extended aldol reaction with a C6 building block that incorporates a C5 unit after decarboxylation. A formal route to lycopene and β-carotene
Since the C15 β-end-group aldehyde 10 ((β-ionylidene) acetaldehyde), an excellent intermediate in the syntheses of retinoids, can be synthesized in many ways from β-ionone, and since the corresponding acyclic C15 ψ-end-group aldehyde 5 can easily be synthesized from citral (1) (Scheme 3), we applied the C15 + C5 route to the syntheses of γ-retinal ((all-E)-8) (Scheme 3) and retinal ((all-E)-13) (Scheme 4), and therefore, by coupling (2 x C20 → C 40), to the preparation of lycopene (14) and β-carotene (15) (Scheme 5). Our new syntheses of retinal ((all-E)-13) and γ-retinal ((all-E)-8 use an extended aldol reaction with a C6 building block that incorporates a C5 unit after decarboxylation.
Valla, Alain,Valla, Benoist,Le Guillou, Regis,Cartier, Dominique,Dufosse, Laurent,Labia, Roger
p. 512 - 520
(2008/02/07)

DIALDEHYDE COMPOUND, PREPARATION METHOD THEREOF, AND SYNTHETIC METHOD OF CAROTENOIDS USING THE SAME
The novel C dialdehyde compound which can be efficiently utilized in the synthesis of carotenoid compounds based on the sulfone chemistry, the preparation method of the same, and the expeditious and practical synthetic processes for lycopene and β-carotene by the use of the above novel compound are disclosed. The syntheses of lycopene and β-carotene are characterized by the processes of the coupling reaction between two equivalents of geranyl sulfone or cyclic geranyl sulfone and the above C dialdehyde, the functional group transformation reactions of the diol in the resulting C 40 coupling products to X's (either halogens or ethers), and the double elimination reactions of the functional groups of the benzenesulfonyl and X to produce the fully conjugated polyene chain of the carotenoids.
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Page/Page column 22

(2010/11/29)

ClO DIALDEHYDE, SYNTHETIC METHOD THEREOF, AND SYNTHETIC METHOD OF BETA-CAROTENE USING THE SAME
The novel intermediate compound which can be efficiently utilized in the synthesis of carotenoid compounds based on the sulfone chemistry, the preparation method of the same, and the practical synthetic process for preparing β-carotene by the use of the above novel compound are disclosed. The synthesis of β-carotene is characterized by the double elimination reactions of the C40 compound containing both the benzenesulfonyl group and the group X (either halogen or ether), which can be prepared by the coupling reaction of the novel C10 dialdehyde with two equivalents of the C15 allylic sulfone, followed by the functional group transformation of the resulting C40 diol either to the corresponding halide or to the ether, to produce the fully conjugated polyene chain.
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Page/Page column 14-15

(2010/10/20)

ISOLATION AND PURIFICATION OF CAROTENOIDS FROM MARIGOLD FLOWERS
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.
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Page/Page column 10-12

(2008/06/13)

Sulfone coupling and double-elimination strategy for carotenoid synthesis
A highly efficient synthetic method of carotenoid compounds has been developed on the basis of the sulfone coupling and double-elimination strategy. This method highlighted the sulfone-mediated coupling with the novel C 10 dialdehyde, 2,7-dimethyl-4-octenedial, which was easily prepared and efficiently utilized in the synthesis of the conjugated polyene chains.
Guha, Samar Kumar,Koo, Sangho
p. 9662 - 9665
(2007/10/03)

COMPOUNDS COMPRISING POLYENE CHAIN STRUCTURE AND PROCESSES FOR PREPARING THE SAME
A process for preparing beta-carotene, represented by Formula 3staring from a sulfone compound of Formula B
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Page 9-10

(2010/02/05)

Synthesis of symmetrical carotenoids by a two-fold Stille reaction
β-Carotene 1 and (3R,3′R)-zeaxanthin 2 have been stereoselectively prepared in a highly convergent fashion by a 2-fold Stille cross-coupling reaction. The C12-pentaenylbis-stannane 8 is the central "lynchpin" that connects two units of the terminal C14-iodides 9 and 17 to afford 1 and 2, respectively.
Vaz, Belen,Alvarez, Rosana,de Lera, Angel R.
p. 5040 - 5043
(2007/10/03)

The organoalkali route to vitamin A and β-carotene
The reductive cleavage of methyl vinyl-β-ionyl ether (1) or the deprotonation of 3,2′,6′,6′-tetramethyl-5-(1-cyclohexenyl)-1, 3-pentadiene (2) gives rise to an organometallic C15 species that combines selectively with a variety of electrophiles at the terminal chain position. Its reaction with aldehydes, however, is less clean. In particular, (E)-β-formyl-2-butenyl acetate gives the expected adduct 7a and, after dehydration, vitamin A acetate only in poor yield. The same is true for the analogous reaction with 2,7-dimethyl-2,4,6-octatriendial, which ultimately affords βcarotene. Vitamin A acetate can also be prepared, this time in moderate yield, by functionalization through consecutive deprotonation, borylation, oxidation and acetylation of a C20 pentaene hydrocarbon having the required skeleton. Both the C15 and the C20 organometallic key intermediates adopt spontaneously a zigzag-like outstretched conformation which, upon electrophilic trapping, directly and exclusively leads to the all-(E) configuration.
Rauchschwalbe, Guenter,Zellner, Armin,Schlosser, Manfred
p. 3903 - 3909
(2007/10/03)

A novel, selective, and efficient route to carotenoids and related natural products via Zr-catalyzed carboalumination and Pd- and Zn-catalyzed cross coupling.
[structure: see text]. A highly efficient and stereoselective protocol for the syntheses of symmetrical and unsymmetrical carotenoids involving Zr-catalyzed carboalumination of conjugated oligoenynes and Pd- and Zn-catalyzed alkenyl-alkenyl coupling has been developed and applied to the syntheses of beta- and gamma-carotene and vitamin A. gamma-Carotene of > or =99% isomeric purity was prepared in three linear steps (five steps overall) from beta-ionone, enyne 8, (E)-ICH=CHBr, and (E)-Me3SiC triple bond CCH=CHBr in 32% overall yield.
Zeng,Negishi
p. 719 - 722
(2007/10/03)

Scalp life conditioner
The present invention is an improved scalp conditioner for conditions related to flaky and inflamed scalp that are commonly associated with dandruff, seborrhea, psoriasis and burns from the use of alkaline based products. The method involves administering the product to the scalp of the head and gently massaging the scalp. It can be administered several times per week.
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(2008/06/13)

Process for making β-carotene
A process for preparing β-carotene, represented by Formula 3 staring from a sulfone compound of Formula B
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(2008/06/13)

Diallylic sulfides as key structures for carotenoid syntheses
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Choi, Hojin,Ji, Minkoo,Park, Minsoo,Yun, In-Kyun,Oh, Seong-Soo,Baik, Woonphil,Koo, Sangho
p. 8051 - 8053
(2007/10/03)

C-15 phosphonate reagent compositions and methods of synthesizing the same
Allenic phosphonate reagent compositions are described which have the formula: STR1 wherein R and R'=C1 -C4 alkyl groups, or R, R'=(CH2)n (n=2 or 3) or ?CH2 C(CH3)2 CH2 !. Also described are methods for forming such allenic phosphonates from ethynyl-β-ionol, and for converting these allenic compounds to allylic phosphonate compounds which can be used in the synthesis of a variety of biologically-active materials.
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(2008/06/13)

Carotenoids enhance vitamin E antioxidant efficiency
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Bohm,Edge,Land,McGarvey,Truscott
p. 621 - 622
(2007/10/03)

Preparation of β-carotene products with a high 9 (Z) content
β-Carotene products with a high proportion of the 9(Z) isomer are prepared starting from mother liquors from the industrial preparation of β-ionylideneethyltriarylphosphonium salts (C15 -triarylphosphonium salts) by Wittig reaction of a C15 -triarylphosphonium salt which has been enriched in the 9Z isomer directly with β-apo-12'-carotenal or else with 2,7-dimethyl-2,4,6-octatrienedial and subsequently with the C15 -triarylphosphonium salt and subsequent thermal isomerization.
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(2008/06/13)

Unique properties of the 11-cis and 11,11′-di-cis isomers of β-carotene as revealed by electronic absorption, resonance Raman and 1H and 13C NMR spectroscopy and by HPLC analysis of their thermal isomerization
In comparison with the all-trans and other cis isomers of β-carotene, the 11-cis and 11,11′-di-cis isomers exhibited the following unique properties. (1) The wavelengths of the Bu+←Ag- (0-0) absorption of these
Hu, Ying,Hashimoto, Hideki,Moine, Gerard,Hengartner, Urs,Koyama, Yasushi
p. 2699 - 2710
(2007/10/03)

Competition between triplet energy transfer and electron transfer of photoexcited C60 in the presence of β-carotene by changing solvent polarity
The electron transfer and triplet energy transfer from β-carotene to photo-excited C60 in polar and nonpolar solvents have been investigated by 532 nm laser flash photolysis with observation of the transient absorption bands in the visible and near-IR regions. The transient absorption band of the triplet state of C60, which appeared immediately after nanosecond laser exposure, was effectively quenched by β-carotene. With the decay of the triplet state of C60, the intense absorption band of the cation radical of β-carotene appeared at 980 nm with a weak absorption shoulder of the anion radical of C60 at 1070 nm in addition to the triplet state of β-carotene at 550 nm. This indicates that electron transfer takes place from β-carotene to the triplet state of C60 in addition to energy transfer from the triplet state of C60 to β-carotene. In nonpolar solvents, triplet energy transfer predominantly takes place. The relative fraction of the two routes was varied by changing the solvent polarity. After electron transfer, the cation radical of β-carotene disappeared by back electron transfer.
Sasaki, Yoshiko,Fujitsuka, Mamoru,Watanabe, Akira,Ito, Osamu
p. 4275 - 4279
(2007/10/03)

Thermal interconversions among 15-cis-, 13-cis-, and all-trans-β-carotene: Kinetics, arrhenius parameters, thermochemistry, and potential relevance to anticarcinogenicity of all-trans-β-carotene
Rates of thermal, cis-trans rearrangement among all-trans-, 15-cis-, and 13-cis-β-carotene have been measured at temperatures in the range 37-69°C. From the resulting specific rate constants, Arrhenius and Eyring parameters are derived. Positions of equilibrium are estimated experimentally and by force field calculations based on the Allinger MM2 program as improved by Roth (MM2-ERW), while enthalpies of activation for cis-trans isomerization to 11-, 9-, and 7-cis-β-carotenes are estimated by application of the Roth program augmented by the inclusion of the quantum mechanical program of Malrieu et al., EVBH (effective valence-bond Hamiltonian), expanded to encompass longer polyenes. Implications of the interaction of strain and delocalization in the rotation about the 7,8 double bond are presented. A procedure has been developed for the small scale preparation of 13-cis-β-carotene by heating all-trans-β-carotene at 80°C for 8 h. Kinetically and thermodynamically accessible at 37°C, 15-cis- or 13-cis-β-carotene or both become candidates for the role of true anticarcinogenic agent, whereupon all-trans-β-carotene would be relegated to the role of reservoir for the active species.
Doering, W. Von E.,Sotiriou-Leventis, Chariklia,Roth
p. 2747 - 2757
(2007/10/02)

Carbonyl coupling reactions catalytic in titanium and the use of commercial titanium powder for organic synthesis
The high thermodynamic stability of titanium oxides formed as the inorganic byproducts in McMurry-type reactions has so far prevented the development of a catalytic procedure for such reductive carbonyl coupling processes. Similarly, a tightly bound oxide layer passivates the surface of commercial titanium, which is unreactive toward organic substrates under conventional conditions. This paper outlines a way to overcome both of these problems. Thus, oxoamides 1a-h can be reductively cyclized to indoles 2a-h using only catalytic amounts of low-valent titanium if the reaction is carried out in the presence of a chlorosilane. Specifically, the method is based upon the in situ generation of an activated titanium species from TiCl3 and Zn in the presence of the substrate, followed by regeneration of titanium chloride from the titanium oxides formed via ligand exchange with the admixed chlorosilane. Its proper choice is crucial for obtaining both good turnover numbers and clean conversions. Depending on the product structure, (TMS)Cl, ClMe2SiCH2CH2SiMe2Cl (5), or ClMe2Si(CH2)3CN (6) was found to be best suited. Similarly, chlorosilanes also effect the activation of commercial titanium powder which may then be used as a performant off-the-shelf reagent for various types of carbonyl and acetal coupling reactions, for the deoxygenation of epoxides and for the reductive cyclization of oxoamides or oxoesters to indoles, benzofurans, and 2-quinolones. Under these conditions retinal can be reductively dimerized to β-carotene in good yield. Moreover, the titanium/ chlorosilane reagent combination exhibits a strong template effect, allowing macrocyclization reactions without recourse to high dilution. Up to 36-membered rings have been closed in that way. 29Si NMR studies provide some insight into the elementary steps responsible for the degradation of the surface oxide layer on titanium by the chlorosilane. The effect of Lewis acid additives on the course of the coupling processes is discussed.
Fürstner, Alois,Hupperts, Achim
p. 4468 - 4475
(2007/10/02)

Interactions between carotenoids and the CCl3O2? radical
The reactions of CCl3O2? (a model of alkyl peroxyl radicals which can be selectively generated in nanoseconds) with a range of carotenoids (β-carotene, septapreno-β-carotene, canthaxanthin, astaxanthin, zeaxanthin, and lutein) in the heterogeneous micellar environment, aqueous 2% Triton X-100, have been studied by pulse radiolysis. For all carotenoids investigated two reaction products, absorbing in the near-infrared region, are observed and assigned to the carotenoid radical cation and an addition radical. With the exception of astaxanthin, the carotenoid radical cation formation is biexponential and the slower component matches the first-order decay of the addition radical. In the case of astaxanthin, no radical cation is formed directly by reaction with CCl3O2?, it is formed exclusively from the decay of the addition radical. The results are discussed in terms of the antioxidant properties of carotenoid pigments.
Hill, Tessa J.,Land, Edward J.,McGarvey, David J.,Schalch, Wolfgang,Tinkler, Jane H.,Truscott, T. George
p. 8322 - 8326
(2007/10/03)

Use of carotenoporphyrins as tumor localizing agents for diagnosis
A process of tumor identification comprising administering a carotenoporphyrin to a tumor-bearing mammalian host and irradiating the mammalian host with light whereupon the carotenoporphyrin, which has been preferentially taken up by the tumor tissue, fluoresces and permits precise identification of the location, size and shape of the tumor tissue. An improved process of synthesizing carotenoporphyrins 1-5 is also provided.
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(2008/06/13)

Process for producing β-carotene, and intermediate compounds useful for the process
Provided is a novel process for readily producing β-carotene by reacting a sulfone compound represented by the general formula (1), (2) or (3) with an alkali, STR1 wherein R represents a phenyl group which may be substituted, R' a protecting group of acet
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(2008/06/13)

Triplet-Sensitized and Thermal Isomerization of All-Trans, 7-Cis, 9-cis, 13-Cis, and 15-Cis Isomers of β-Carotene: Configurational dependence of the Quantum Yield of Isomerization via the T1 State
The products of triplet-sensitized photoisomerization (excitation at 337 nm of the sensitizer, anthracene) and thermal isomerization of β-carotene in n-hexane, starting from the all-trans, 7-cis, 9-cis, 13-cis, and 15-cis isomers, were analyzed by HPLC.Direct photoisomerization (excitation at 488 and 337 nm) was also examined for comparison.Three different isomerization patterns were found in both triplet-sensitized and thermal isomerization: pattern A, cis to trans isomerization around each cis bond; pattern B, trans to cis isomerization in the central part of the conjugated chain; and pattern C, cis to another cis isomerization.In the T1 state, the pattern A isomerization was predominant even for the peripheral-cis (7-cis and 9-cis) isomers and its efficiency was extremly high for the central-cis (13-cis and 15-cis) isomers.In the S0 state, the pattern B isomerization, instead, was predominant for the peripheral-cis isomers, and the pattern A isomerization was predominant only for the central-cis isomers.The quantum yields of triplet-sensitized isomerization (decrease of the starting isomer per triplet species generated) were determined to be as follows: all-trans, 0.04; 7-cis, 0.12; 9-cis, 0.15; 13-cis, 0.87; and 15-cis, 0.98.In direct photoisomerization, the quantum yield of isomerization at 488-nnm (337 nm) excitation was 4 (3) orders of magnitude lower than the above values, the relative values among the isomers being similar to the above.Further, the overall isomerization patterns of direct photoexcitation were similar to those of triplet-sensitized isomerization, supporting the idea that isomerization takes place via the T1 state even in the case of direct photoexcitation.Carbon-carbon ? bond orders of model polyenes in the T1 and S0 states were calculated by using the Pariser-Parr-Pople CI theorie; bond lengths were optimized by using a bond order-bond length relationship.Isomerization characteristics in the T1 and S0 states observed were discussed based on the results of the calculations.
Kuki, Michitaka,Koyama, Yasushi,Nagae, Hiroyoshi
p. 7171 - 7180
(2007/10/02)

Phosphonate reagent compositions
Novel phosphonate compounds of the formula STR1 are disclosed and claimed, as well as methods for manufacturing the phosphonates from C-14 through C-16 aldehydes. The phosphonate compounds of the present invention can be employed to form 13-cis retinoic acid, retin-A and beta-carotene.
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(2008/06/13)

Sulfone polyene intermediates
A process for producing carotenoids and carotenoid intermediates via reduction of sulfonyl polyenes with a dithionite in the presence of ammonia or an aliphatic amine, including novel intermediates in this process, which carotenoids are known coloring agents for foodstuffs, animal feeds, pharmaceuticals, etc.
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(2008/06/13)

Dihydropyridine spray, process for its preparation and its pharmaceutical use
A sprayable liquid formulation comprising, per 100 ml of the formulation, (a) 0.2 to 5 grams of a dihydropyridine of the formula STR1 in which R1 and R2 each independently is alkyl with 1 to 10 carbon atoms optionally substituted by alkoxy with 1 to 3 carbon atoms, trifluoromethyl, halogen or N-methyl-N-benzylamino, R3 is alkyl with 1 to 4 carbon atoms, cyano or hydroxymethyl, and X is a nitro group, one or two chlorine groups or the ring member =N--O--N=, (b) 10 to 40 grams of polyethylene glycol with an average molecular weight of 200 to 600, (c) 25 to 60 grams of ethyl alcohol, and (d) 3 to 15 grams of polyvinylpyrrolidine with an average molecular weight of 12000 to 30000.
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(2008/06/13)

Palladium-Catalyzed Allylidenation of Aldehyde. A Simple and Convenient Method for the Preparation of Conjugated Diene and Polyene Compounds
Allylic phenylcarbamates prepared from allylic alcohols and phenyl isocyanate in situ reacted with aldehydes to give conjugated dienes in good yields in the presence of tributylphosphine and a catalytic amount of Pd(PPh3)4.This method proved to be suitable for the preparation of polyene compounds such as carotenoids.
Okukado, Nobuhisa,Uchikawa, Osamu,Nakamura, Yukari
p. 1449 - 1452
(2007/10/02)