Showing papers on "Flavanone published in 1994"
TL;DR: Flavonoids, mainly derivatives of flavone and flavonol, clearly demonstrated the suppressive effects on lymphocyte proliferation at higher than 10(-6) M depending on the structures of flavonoid molecules, although their suppressive activities were less than that of cyclosporin A or prednisolone.
85 citations
TL;DR: In this article, the authors analysed twenty samples of Portuguese heather honey and found that the most characteristic substances were myricetin, tricetin 3-methyl ether, and trico-ethyl ether.
Abstract: The flavonoids present in twenty samples of Portuguese heather honey were analysed by reversed-phase HPLC. The flavonoid fraction was purified by a combination of chromatography on Amberlite XAD-2 and Sephadex LH-20 columns. The total amount of flavonoids ranged between 60 and 500 μg/100g honey, values which are much smaller than those previously found for Spanish rosemary honey samples (500-2000 μg/100 g honey). The main flavonoids present in Portuguese heather honey were the flavanones pinocembrin and pinobanksin and the flavones chrysin and galangin. These analyses showed that all the samples contained a similar flavonoid pattern composed of at least 22 compounds. The most characteristic substances were myricetin, myricetin 3-methyl ether, myricetin 3'-methyl ether and tricetin. These four flavonoids have in common the structural feature of having a trioxygenated ring B (3',4',5'-trioxygenation), this being an attribute not found in the flavonoids detected in any other honey sample of different plant origin analysed so far, suggesting that these substances could probably be used as markers for the botanical origin of heather honey.
84 citations
TL;DR: A reversed phase high-performance liquid chromatographic method has been developed for the qualitative and quantitative analysis of a caffeic acid derivative, rosmarinic acid, and the main flavone and flavanone glycosides in leaves of Mental×piperita as mentioned in this paper.
Abstract: A reversed-phase high-performance liquid chromatographic method has been developed for the qualitative and quantitative analysis of a caffeic acid derivative, rosmarinic acid, and the main flavone and flavanone glycosides in leaves of Mental×piperita, namely eriocitrin, luteolin 7-O-rutinoside, hesperidin, isorhoifolin, diosmin, eriodictyol 7-O-glucoside, and narirutin. The last two were identified for the first time in M.×piperita and Mentha genus, respectively. Forty cloner, belonging to the three varieties of M.×piperita, were investigated. The eight phenolic constituents are present in all clones. The flavonoid content of the leaves ranged from 8.6 to 11.8% on dry weight basis
75 citations
TL;DR: In this article, a fast and simple method has been developed to detect orange juice (Citrus sinensis) falsifications on the basis of the flavanone glycoside pattern.
Abstract: A fast and simple method has been developed to detect orange juice (Citrus sinensis) falsifications on the basis of the flavanone glycoside pattern. After a short sample preparation procedure, gradient HPLC is used, followed by photodiode array detection. Separation is done by means of a 15 cm Waters Novapak RP 18 column and a mobile phase gradient, partly replacing an aqueous phosphate buffer solution by acetonitrile. Peak identification is based on relative retention times as well as on UV-vis spectra. On the basis of a minimum hesperidin/narirutin ratio of 3, some doubtful technological processes, as further extraction of oranges, may be traced out, as well as the addition of Citrus reticulata and some orange hybrids
60 citations
TL;DR: In this paper, the root bark of Artocarpus heterophyllus has been isolated and characterized from the root tree of the tree and four known compounds, β-sitosterol, betulin, ursolic acid and betulinic acid have been characterized.
26 citations
TL;DR: In this article, a new flavanone was isolated from the chloroform extract of the roots of Tephrosia maxima along with maxima isoflavone J and t.
20 citations
20 citations
TL;DR: In this paper, a high-performance liquid chromatographic procedure for the analysis of the different flavonoids found in Citrus aurantium tissue extracts has been developed, employing a C18 reverse phase column and an elution isocratic-gradient system with a mixture of water, methanol, acetonitrile and acetic acid.
Abstract: A high-performance liquid chromatographic procedure for the analysis of the different flavonoids found in Citrus aurantium tissue extracts has been developed. It employs a C18 reverse phase column and an elution isocratic-gradient system with a mixture of water, methanol, acetonitrile and acetic acid. We make an exhaustive description of the optimisation process by studying the quantitative chromatographic parameters: k1, w, a, N, HETP and R. The use of different extraction solvents for flavonoids in Citrus aurantium tissues was also studied, DMSO presenting the best results. Twelve compounds were detected, isolated and their spectral structures characterized.
18 citations
TL;DR: Two new C-methyl flavanone derivatives, isolated from the Matteuccia orientalis (Hook.) Trev.
Abstract: Matteuorienate A and B, two new C-methyl flavanone derivatives, were isolated from the Matteuccia orientalis (Hook.) Trev. (Aspidiaceae), and their structures were determined by the use of spectroscopic methods including 2D-NMR (1H-1H COSY, 1H-13C COSY and 1H-13C long-range COSY) experiments and chemical methods. Both the compounds were found to be very strong inhibitors of aldose reductase among the natural products.
17 citations
TL;DR: A prenylated flavanone was isolated from the roots of Maackia amurensis subsp. buergeri as discussed by the authors, and the structure of the new compound was characterized as 8,5′-di (γ,γ-dimethylallyl-5,2′,4′-trihydroxy-7-methoxyflavanone).
16 citations
TL;DR: In this paper, three new flavanone derivatives named sorocein C (2), SORCEIN D (1) and SORECEIN H (3) together with the known artonin D, kuwanon C, cyclo-morusin, and kUwanon J were isolated from the methanolic extract of the roots of Sorocea bonplandii.
Abstract: Three new flavanone derivatives named sorocein C (2), sorocein D (1) and sorocein H (3) together with the known artonin D, kuwanon C, cyclo- morusin, and kuwanon J were isolated from the methanolic extract of the roots of Sorocea bonplandii. The structures were assigned on the basis of spectroscopic evidences
TL;DR: Arylation of 3-(phenylsulfonyl)chroman-4-one with simple aryllead triacetates affords the corresponding 3-aryl-3-phenyl sulfonyl (3-S-SFL) chroman-1 in 64-74% yield as discussed by the authors.
Abstract: Arylation of 3-(phenylsulfonyl)chroman-4-one 1 with simple aryllead triacetates affords the corresponding 3-aryl-3-(phenylsulfonyl)chroman-4-one in 64–74% yield. However, no reaction took place with the hindered 2,4,6-trimethoxyphenyllead triacetate 9. Reaction of the 8-triacetoxyplumbylflavane derivative 10 with 4′-methoxy-3-(phenylsulfanyl)flavanone 11 afforded the biflavanone 12 in 64% yield. Nickel boride reduction of compound 12 led to the chalcone 13, which was recyclised to the Garcinia-type (I-3, II-8) biflavanone 14. Dimethyldioxirane oxidation of 12 gave the flavone-flavanone 15.
TL;DR: In this article, the structures of the flavonoids isolated from the roots of Scutellaria ramosissima have been established on the basis of chemical transformations and spectral characteristics.
Abstract: The new 2(S)-2′,5-dihydroxy-7-β-D-glucopyranosyloxyflavanone has been isolated from the epigeal part ofScutellaria ramosissima M Pop Oroxylin A, woganin, 2′,6′-trihydroxy-6,7,8-trimethoxyflavone, and vanillic and syringic acids, and also the new substance 5,6-dihydroxy-7,8-dimethoxyflavone, have been isolated from the roots of this plant for the first time The structures of the flavonoids isolated have been established on the basis of chemical transformations and spectral characteristics
TL;DR: The 8-triacetoxyplumbylflavane derivative 8-(3-oxobenzofuran-2-yl)flavanone as mentioned in this paper was prepared in 4 steps in 28% overall yield from 4′,5,7-flat-1.
Abstract: The 8-triacetoxyplumbylflavane derivative 11 was prepared in 4 steps in 28% overall yield from 4′,5,7-flavanone. It reacted with the benzofuranone ally β-keto ester 12 to yield a 8-(benzofuran-2yl)flavanone 13 in 66%. Removal of the allyl ester group and cleavage of the dioxolane ring afforded the 8-(3-oxobenzofuran-2-yl)flavanone. This reaction shows that complex polyfunctional aryllead triacetates can be made and selectively coupled with activated ketones.
TL;DR: A new dihydroflavonol, plumbaginol, has been isolated from the aerial parts of Plumbago indica and its structure elucidated as 3,5,3′-trihydroxy-6,7-methylenedioxy-8,5′-dimethoxy-2 R :3 R -flavanone by spectroscopic studies.
TL;DR: It is concluded that a non-steroidal non-arachidonate-mediated potent anti-inflammatory agent based on this compound could be developed with IL-1 blocking activity, however, flavanone hydrazone was rather toxic at effective doses tested and modification of the chemical structure to reduce its side-effects would seem essential.
Abstract: Yao Q-S, Varma RS, Liu SXL, Chiou GCY. Prevention of lens protein-, endotoxin-, and interleukin-1-induced uveitis with chalcone derivatives. Inflammopharmacology. 1994;2:401-409. In order to develop potent non-steroidal anti-inflammatory agents, a new class of agents unrelated to those known to inhibit the arachidonate cascade were investigated. Most of the chalcone derivatives studied, including flavanone hydrazone (RCV/FLV 574), 2’-(o-hydroxyphenol)-5-phenylpyrazoline (RCV-556Pz), 2’-acetoxychalcone-iV-monoacetylhydrazone (RVC-576) and 7V-(o-hydroxybenzoyl) morpholine (RVC-570), inhibited lens protein-induced ocular inflammation effectively at a dose level of 1% (50 μ1 as did prednisolone. Flavanone hydrazone (RCV/FLV 574) was the only compound among all these derivatives which inhibited endotoxin- and interleukin-1 (IL-1)-induced uveitis at 3 mg/kg ip tid this being approximately 7-fold more potent than prednisolone at 20 mg/kg ip tid. It is concluded that a non-steroidal non-arachidonate-mediated potent anti-inflammatory agent based on this compound could be developed with IL-1 blocking activity. However, flavanone hydrazone was rather toxic at effective doses tested. Modification of the chemical structure to reduce its side-effects would, therefore seem essential.
TL;DR: In this article, a C18 reverse phase column and an elution isocratic-gradient system was used with a mixture of water, acetonitrile and acetic acid for elucidation of Citrus flavanone glycosides in biosynthesis and their respective dihydrochalcones.
Abstract: A high-performance liquid chromatographic method for the elucidation of the principal Citrus flavanone glycosides in biosynthesis and their respective dihydrochalcones has been developed. A C18 reverse phase column and an elution isocratic-gradient system is used with a mixture of water, acetonitrile and acetic acid. We describe the optimization process by studying the influence of the structural characteristics of these compounds on the quantitative chromatographic parameters: k′, w and R.
01 Jan 1994
TL;DR: Arylation of 3-(phenylsulfonyl)chroman-4-one with simple aryllead triacetates affords the corresponding 3-aryl-3-phenyl sulfonyl (3-S-SFL) chroman-1 in 64-74% yield as discussed by the authors.
Abstract: Arylation of 3-(phenylsulfonyl)chroman-4-one 1 with simple aryllead triacetates affords the corresponding 3-aryl-3-(phenylsulfonyl)chroman-4-one in 64–74% yield. However, no reaction took place with the hindered 2,4,6-trimethoxyphenyllead triacetate 9. Reaction of the 8-triacetoxyplumbylflavane derivative 10 with 4′-methoxy-3-(phenylsulfanyl)flavanone 11 afforded the biflavanone 12 in 64% yield. Nickel boride reduction of compound 12 led to the chalcone 13, which was recyclised to the Garcinia-type (I-3, II-8) biflavanone 14. Dimethyldioxirane oxidation of 12 gave the flavone-flavanone 15.
Patent•
10 Aug 1994
TL;DR: An anti-MRSA compound comprising of the formula which is generally extracted from the root of Sophora exigua is described in this paper, where the usage of this compound is for methicillin-resistant Staphylococcus aureus.
Abstract: An anti-MRSA compound comprising of the formula which is generally extracted from the root of Sophora exigua. The usage of this compound is for methicillin-resistant Staphylococcus aureus.
TL;DR: The 8-triacetoxyplumbylflavane derivative 8-(3-oxobenzofuran-2-yl)flavanone as discussed by the authors was prepared in 4 steps in 28% overall yield from 4′,5,7-flat-1.
Abstract: The 8-triacetoxyplumbylflavane derivative 11 was prepared in 4 steps in 28% overall yield from 4′,5,7-flavanone. It reacted with the benzofuranone ally β-keto ester 12 to yield a 8-(benzofuran-2yl)flavanone 13 in 66%. Removal of the allyl ester group and cleavage of the dioxolane ring afforded the 8-(3-oxobenzofuran-2-yl)flavanone. This reaction shows that complex polyfunctional aryllead triacetates can be made and selectively coupled with activated ketones.