Synthetic and modified isoflavonoids. XI. Synthesis of analogues of maxima isoflavone A and xanthocercin

Analogues of maxima isoflavone A and of xanthocercin containing benzodioxolane, benzodioxane, and benzodioxepane fragments in rings A and B of isoflavone have been synthesized. The structures of the compounds obtained have been confirmed by analytical and spectral characteristics.KIEN, Karakalpak Division, Academy of Sciences of the Republic of Uzbekistan, Nukus. Taras Shevchenko Kiev University. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 337–343, May–June, 1994.     

Synthetic and modified isoflavonoids. XIII. Synthesis of analogues of fujikinin

Analogues of a natural isoflavone glycoside — fujikinin — have been synthesized. Their structures have been confirmed by their PMR spectra.Taras Shevenko Kiev University: KIEN, Karakalpak Division, Academy of Sciences of the Republic of Uzbekistan, Nukus. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 347–351, May–June, 1994.     

Synthetic and modified isoflavonoids XVII. Interaction of synthetic analogs of isoflavones with guanidine

Under the influence of guanidine, 1,3-benzodioxolane, 1,4-benzodioxane, and 1,5-benzodioxepane analogs of isoflavone are converted into 2-aminopyrimidine derivativesTranslated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 636–640, September–October, 1994.     

Atropo-isomerism and abnormal temperature dependence of paramagnetic shifts in 1H NMR spectra of heterocyclic analogs of isoflavones in the presence of lanthanide chelates

It has been found that spatially hindered analogs of isoflavones can occur as a mixture of atropo-isomers, which is conveniently detected by using optically active lanthanide shift reagents. It is shown that on lowering the temperature the individual shifts of the signals of the isoflavone protons can either increase or decrease. The observed anomalies are attributed to changes in the predominant conformations of the molecules as the temperature is varied.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 5, pp. 629–633, September–October, 1989.     

Synthesis of 7-O-β-D-glucopyranosides of isoflavones and their heterocyclic analogues

The products of the interaction of -acetobromoglucose with 2,4,5-trihydroxyphenyl benzyl ketone and 2,4-dihydroxyphenyl 4-hydroxybenzyl ketone and also with their heterocyclic analogues, which are present completely or partially in the enolic form, have been investigated. It has been shown that in this reaction a tetra-O-acetylglucosyl residue is added at the 4-OH hydroxy group of the phenyl residue of the ketone. The compounds obtained have been converted into isoflavone 7-O-glucosides by the action of the vilsmeier reagent or acetoformic anhydride.Taras Shevchenko Kiev University. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 220–227, March–April, 1993.     

Photophysics of Genistein isoflavone: Solvent and concentration effects studied by UV–visible spectroscopy and theoretical simulation

Genistein isoflavone is shown to exist in two different conformations which are the 90° completely twisted geometry and the 50° less twisted one. Specific interactions with the solvent cage as well as self-association processes seem shifting the isoflavone from the perpendicular conformation towards the less twisted one. The theoretical simulation, using analytical atom–atom pair potential, predicts a self-dimer in a slipped non-sandwich, face to river, perpendicular structure. From the UV–visible photophysics investigations it is revealed that monomeric species cannot exist alone even at very low solute concentration (10⁻⁶ M), the self-association process occurs already in this concentration range.     

A new isoflavonostilbene from the heartwood of Maackia amurensis

A new isoflavonostilbene which has been called maackiasin has been isolated from an ethanolic extract of the heartwood ofMaackia amurensis and its structure has been established by spectral methods. The maackiasin molecule is constructed of fragments of the isoflavone retusin and of 3,3,4,5-tetrahydroxystilbene linked by a diether bond. The dioxane grouping connecting the two fragments is constructed from the hydroxyls at C-7 and C-8 of the isoflavone and the vinyl grouping of the stilbene. Maackiasin is the first representative of a new type of natural polyphenols.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 39–42, January–February, 1986.     

Phenolic compounds of Ononis arvensis the structure of onogenin

Summary From the roots ofOnonis arvensis L. a new isoflavone has been isolated with mp 213–214° C which has been called onogenin. On the basis of the results of a study of its UV, IR, NMR, and mass spectra, the structure of 7-hydroxy-6-methoxy-3,4-methylenedioxyisoflavanone is proposed for onogenin.Khar'kov State Pharmaceutical Institute. Khar'kov Scientific-Research Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 354–357, May–June, 1975.     

Flavonoids of Thermopsis alterniflora

Summary From the lipophilic fraction of the substances from the herbage ofThermopsis alterniflora we have isolated a molecular compound of two flavonoids, one of which has been identified as chrysoeriol, while the second, with the composition C₁₆H₁₂O₅, mp 274–275°C, is a new isoflavone which we have called teralin. On the basis of spectral characteristics and the products of alkaline fusion, we have proposed for it the structure of 4,7-dihydroxy-2-methoxyisoflavone.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 140–144, March–April, 1975.     

Preparation and reactions of isoflavone heteroanalogs (a review)

Methods for preparation of 3-hetarylchromones, which are isoflavone heteroanalogs, and the reactions of these compounds with either preservation or opening of the pyrone ring are reviewed.Taras Shevchenko Kiev University, 252033 Kiev, Ukraine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 3–23, January, 1999     

Alkylation of 7-hydroxy-3-furylchromone and 7-hydroxyisoflavone with halogen derivatives of the heterocyclic series

Products of the alkylation of compounds of the isoflavone type-7-hydroxyisoflavone, 2-methyl-7-hydroxyisoflavone, 2-ethoxycarbonyl-7-hydroxyisoflavone, 2-methyl-5,7-dihydroxyisoflavone, 2-methyl-3-furyl-7-hydroxychromone, and 2-ethoxycarbonyl-3-furyl-7-hydroxychromone — were obtained by reaction with chloromethyl derivatives of heterocycles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1321–1323, October, 1972.     

Synthesis of sterically hindered benzodioxane analogs of isoflavone and a study of their atropoisomerism

Syntheses are reported far sterically hindered 2-substituted benzodioxane analogs of isoflavone. An optically active lanthanide shift reagent (LSR) was used to show that these products exist as mixtures of atropoisomers. The difference in the chemical shifts of the enantiomeric protons in the presence of the LSR may reach 2–3 ppm with decreasing temperature. Conclusions were drawn concerning the structure of the LSR-substrate adducts and their conformations.Taras Shevchenko Kiev University, 252033 Kiev. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 902–908, July, 1996. Original article submitted March 27, 1996.     

Thiazole analogs of chalcone and flavone

New thiazole analogs of chalcones and their epoxides were obtained. Thiazole analogs of flavone and isoflavone were synthesized for the first time on the basis of these compounds. It is shown that o-hydroxyphenylpyrazole derivatives are formed by the action of hydrazine hydrate on 2-(4-thiazolyl)chromones. The PMR spectra of the new substances are presented and discussed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1202–1208, September, 1981.     

Soy Isoflavones Inhibit Both GPIb-IX Signaling and αIIbβ3 Outside-In Signaling via 14-3-3ζ in Platelet

Soy diet is thought to help prevent cardiovascular diseases in humans. Isoflavone, which is abundant in soybean and other legumes, has been reported to possess antiplatelet activity and potential antithrombotic effect. Our study aims to elucidate the potential target of soy isoflavone in platelet. The anti-thrombosis formation effect of genistein and daidzein was evaluated in ex vivo perfusion chamber model under low (300 s⁻¹) and high (1800 s⁻¹) shear forces. The effect of genistein and daidzein on platelet aggregation and spreading was evaluated with platelets from both wildtype and GPIbα deficient mice. The interaction of these soy isoflavone with 14-3-3ζ was detected by surface plasmon resonance (SPR) and co-immunoprecipitation, and the effect of αIIbβ3-mediated outside-in signaling transduction was evaluated by western blot. We found both genistein and daidzein showed inhibitory effect on thrombosis formation in perfusion chamber, especially under high shear force (1800 s⁻¹). These soy isoflavone interact with 14-3-3ζ and inhibited both GPIb-IX and αIIbβ3-mediated platelet aggregation, integrin-mediated platelet spreading and outside-in signaling transduction. Our findings indicate that 14-3-3ζ is a novel target of genistein and daidzein. 14-3-3ζ, an adaptor protein that regulates both GPIb-IX and αIIbβ3-mediated platelet activation is involved in soy isoflavone mediated platelet inhibition.     

Use of lanthanide shift reagents for studying pyridine analogs of isoflavones

The interaction of lanthanide shift reagents (LSR) with pyridine analogs of isoflavone and their derivatives has been studied. It was found that the pyridine nitrogen atom can increase the coordinating ability of electron donor groups in the molecule, in particular the sulfur atom in chromone thiones. It has been shown that LSR interact actively with pyridinium methylsulfate salts containing the 3-chromone substituent. The efficiency of the coordination is influenced by the occurrence of steric hindrance around the chromone carbonyl. The structure of the adducts of these salts with LSR is discussed.Taras Shevchenko University, Kiev 252033, Ukraine. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 342–345, March, 1998.     

Synthetic and modified isoflavonoids. II. Synthesis of new 2,6-dialkyl-substituted analogues of pseudobaptigenin

New 2,6-dialkyl-substituted isoflavone analogues of the natural isoflavone pseudobaptigenin have been synthesized. Their structures have been confirmed by IR and PMR spectroscopies.     

Synthesis and structure of amino esters of menthol

The conditions for the acylation of (–)-menthol with monochloroacetyl chloride have been studied. Amino esters of (–)-menthol have been obtained by the nucleophilic replacement of the chlorine in (–)-menthol monochloroacetate by residues of secondary amines. Their properties and their mass, IR, and¹³C NMR spectra are described.Institute of Physical Organic Chemistry, Academy of Sciences of the Belorussian SSR, Minsk. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 728–733, November–December, 1981.     

Nonempirical calculations of potential-energy surfaces for nucleophilic addition of H− and F− to an acetylene molecule

The minimal energy paths for the nucleophilic addition of a hydride ion (H^–) and a fluoride ion (F^–) to a molecule of acetylene (A) have been calculated with the use of 3–21++G and 3–21+G double basis sets in the framework of the Hartree-Fock-Roothaan method. The values of the total energies of the reactants, transition states, and products have been refined by means of calculations with more complete basis sets [6–31++G// 3–21++G and 6–31++G*//3–21++G for reaction (1); 6–31+G*//3–21+G and 6–31++G**//3–21+G for reaction (2)] and by taking into account the correlation energy for reaction (1) in the framework of the SCEP/6–31++*//3–21++G method. It has been established that the activation energy of reaction (2) is 15.94 kJ/mole lower than that for reaction (1), that reaction (1) is exothermic, and that the enthalpy change accompanying reaction (2) is close to zero. The character of the distribution of the electron density along the minimal energy paths of both reactions has been analyzed, and the differences appearing as a result of the replacement of the soft nucleophile H^– by the harder nucleophile F^– have been ascertained. The results of the calculations have been compared with the results available in the literature for reaction (1).Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 25, No. 2, pp. 149–155, March–April, 1989.     

Synthesis,spectroscopic characterization and redox properties of titanium and vanadium substituted Keggin-type heteropolyanions

The Ti-substituted heteropolytungstates K7[TiIVW11–BO40] and K6[VVTiIVW10PO40] have been synthesized and characterized by elemental analyses and spectroscopic techniques. Their redox properties have been studied by cyclic voltammetry, and the compounds were found to be more difficult to reduce than the unsubstituted heteropolyanion. The one- and two-electron reduced heteropoly blues of [VVTiIVW10PO40]6–, namely [VIVTiIVW10PO40]7– and [VIVTiIIIW10PO40]8–, have also been prepared by chemical methods. Their optical spectra show low-energy intervalence charge-transfer bands as well as the expected d–d transitions. The optical and e.s.r. investigations indicate that VIV and TiIII are not vicinal in [VIVTiIIIW10PO40]8–.     

Antioxidant Potential and Cytotoxic Effect of Isoflavones Extract from Thai Fermented Soybean (Thua-Nao)

Thua-nao, or Thai fermented soybeans, is a traditional Lanna fermented food in Northern Thailand. It is produced by using a specific bacterial species called Bacillus subtilis var. Thua-nao. We investigated the antioxidant activity and cytotoxic effect of isoflavones from Thua-nao. The phenolic compound contents and total flavonoid contents were determined by spectrophotometry. The antioxidant activity was examined using the ABTS, FRAP, and DPPH assays. The isoflavone contents and phenolic compositions were examined by the high-performance liquid chromatography (HPLC) and liquid chromatography-mass spectrometry (LC-MS) techniques. The ability of isoflavones to inhibit human cancer cell growth was assessed by the MTT assay. The total phenolic content, total flavonoid content, and antioxidant activities of the isoflavones were 49.00 ± 0.51 mg GAE/g of dry extract (DE), 10.76 ± 0.82 mg QE/g of DE, 61.03 ± 0.97 µmol Trolox/g of DE, 66.54 ± 3.97 µM FeSO₄/g of DE, and 22.47 ± 1.92% of DPPH inhibition, respectively. Additionally, the isoflavone extracts from Thua-nao had high isoflavone contents and polyphenolic compound compositions, especially daidzein and genistein. The isoflavone demonstrated a weak inhibition of MCF-7 and HEK293 cancer cell growth. It has a high antioxidant component, which is beneficial and can be developed for new therapeutic uses. However, further studies on the benefits of Thua-nao should be performed for realizing better and more effective uses soon.