Lipids ofOriganum tytthanthum

The composition of lipids and fatty acids from the above-ground part ofOriganum tytthanthum Gontsch. (Lamiaceae) is studied. Lipids from the air-dried plant material are enriched in glycolipids, essential fatty acids, and biologically active lipophilic substances. The free fatty acids include 15-methylhexadecanoic acid (0.5 % by GLC).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 100–102, March–April, 2000.     

Fruits of two seabuckthorn varieties

Fruits of two varieties of Hippophae rhamnoides L. collected in Kyrgyzstan (I) and Uzbekistan (II) were investigated. Differences in their morphological and biochemical properties were demonstrated. Titrable acids, ascorbic acid, and protein dominated in the fruits of I. Pulp oil of II contained more free fatty acids (acid number 2.9 mg KOH) and carotinoids (419.3 mg%). The principal pulp acid was 16:1. Among the rarely encountered acids of pulp oil, an insignificant quantity of 16:2 was detected (1.2–4.6%). Seed oil of the studied specimens contained >40% of the essential acids 18:2 and 18:3 (vitamin F).Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 435–437, November–December, 2004.This revised version was published online in April 2005 with a corrected cover date.     

Lipids and essential oil ofOriganum onites

Neutral lipids, glycolipids, phospholipids, pigments, and essential oil of the above-ground part ofOriganum onites L. (Lamiaceae) are isolated and characterized for the first time. The fatty-acid composition of the lipids and the components of the hydrocarbons, sterols, and essential oil are determined by GC/MS. Linolenic and palmitic acids dominate in the acids of the lipids. The main components of the hydrocarbons are nonacosane; of the sterols, \-sitosterol; of the pigments, chlorophylls a and b. A total of 54 components are identified in the essential oil.Presented at the IIIrd International Symposium on the Chemistry of Natural Compounds, Bukhara, Uzbekistan, 19–22 December, 1998.Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 106–109, March–April, 2000.     

Chemical study of triterpenoid resinous materials in archaeological findings by means of direct exposure electron ionisation mass spectrometry and gas chromatography/mass spectrometry

A systematic study of standard triterpenes (alpha-amyrine, oleanolic acid, betulin, lupeol, betulinic acid and lupenone) and of raw resinous materials (frankincense resin, mastic resin and birch bark pitch) was performed using direct exposure electron ionisation mass spectrometry (DE-MS) and gas chromatography/mass spectrometry (GC/MS). DE-MS provides a mass spectral fingerprint of organic materials in a few minutes which highlights the compounds that are the main components in the sample. The application of principal component analysis (PCA) on DE-MS data in the mass ranges m/z 181-260 and m/z 331-500, corresponding to the fragmentation of triterpenoid molecules, enabled us to distinguish between different triterpenoid materials such as mastic resin, frankincense resin and birch bark pitch, and to graphically plot the resinous substances in three separate clusters, retaining 89% of the total variance. GC/MS analysis of the same materials has permitted us to elucidate in detail the molecular composition and to identify minor components and species that act as markers of the degradation undergone by the materials. The paper also reports the results for the organic residues contained in an Egyptian censer (5th-7th century AD) which was recovered in the excavation of the Necropolis of Antinoe (Egypt), and for the hafting material found on a Palaeolithic tool recovered at the site of Campitello (Arezzo, Tuscany), dating back to the Mid-Pleistocene period. Although DE-MS was found to be a fast analytical tool, it failed to give any information on the presence of less abundant compounds when applied to mixtures of different materials: only mastic resin was found in the residues from the Roman censer, whereas GC/MS analysis identified the presence of a vegetable oil from Brassicaceae seeds and Pinaceae resin. Birch bark pitch as a pure material was identified in the sample from the Palaeolithic flint flake using both procedures.     

A study of early colour change due to simulated accelerated sunlight exposure in Scots pine (Pinus sylvestris)

A detailed study of early colour change in Scots pine (Pinus sylvestris) due to accelerated simulated sunlight exposure was undertaken focusing on the first 24 h of change. Colour changes were monitored with a Datacolor check spectrophotometer and compared with a set of controls. Measurements on both samples and controls were performed hourly for the first 24 h and there after daily until 168 h’ exposure with extra measurements at 200, 350 and 500 h. A subset of samples was extracted prior to exposure to check the effects of any colour change due to the presence of extractives. Data was analysed using the reflectance spectra (400–700 nm) as well as the CIE-L^*a^*b^* system and ΔE. The majority of colour changes were found to occur within the first 24 h. This was unaffected by the removal of extractives from the wood and was independent of temperature. Mechanical properties and weight changes were also monitored to allow a comparison of sensitivity between the differing methods.     

Thermal analysis and gas chromatography coupled mass spectrometry analyses of hydroxypropyl-β-cyclodextrin inclusion complex containing Lippia gracilis essential oil

Inclusion complexation with cyclodextrins is an effective way to improve stability and turn liquid materials into re-dispersible and easy-to-handle powders. In the present work, the complexation of L. gracilis essential oil, already recognized as a potent larvicide material, with hydroxylpropyl-β-cyclodextrin was performed using slurry and paste procedures and the complexes obtained were evaluated. The gas chromatography coupled to mass spectrometry (GC/MS) analysis showed a total volatile content of 99.24% in the L. gracilis oil. The characterization of the complex involved the analysis of the original essential oil, the surface, and the total extracted oils. The major components in L. gracilis essential oil were identified as carvacrol (23.52%), p-cymene (15.82%), γ-terpinene (14.17%), and thymol (7.27%). GC/MS results showed significant differences between the original oil, the slurry, and paste complexation. Thermal characterization indicates the occurrence of complexation, mainly in paste complexes, which presents a TG–DTA peak at 230–275 °C, probably related to oil loss.     

<Emphasis Type="Italic">Ferula gummosa</Emphasis> Fruits: An Aromatic Antimicrobial Agent

Ferula gummosa Boiss. (Apiaceae) fruit volatile oil was analyzed by GC/MS. Seventy-three components (96.89%) were identified, and the major components were β-pinene (43.78%), α-pinene (27.27%), and myrcene (3.37%). The antimicrobial activity of the oil was tested on three strains of Gram positive bacteria (Staphylococcus aureus, S. epidermis, and Bacillus subtilis), three strains of Gram negative bacteria (Escherichia coli, Salmonella typhi, and Pseudomonas aeruginosa), and two strains of fungi (Candida albicans and C. kefyr). The essential oil remarkably inhibited the growth of the tested microorganisms. The results indicate that the fruits have potential for use as an aromatic antimicrobial agent.__________Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 252–254, May–June, 2005.     

Hydrolyzed tannins ofEuphorbia glareosa leaves. Structure of glarein A

A new dimeric hydrolyzed tannin called glarein A (1) is isolated fromEuphorbia glareosa Pall. ex Bieb. leaves. Glarein A consists of two D-glucose residues, two valoneaylic groups, and two gallic acids. The structure is established by chemical reactions and UV, IR, and PMR spectra.I. G. Kutateladze Institute of Pharmacochemistry, Academy of Sciences of Georgia. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 112–114, March–April, 2000.     

Synthesis and reactivity of chiral pentavalent bismuth derivatives

Eight new pentavalent organobismuth derivatives were synthesized by the reactions of triphenylbismuth or phenyl-2,2"-biphenylenebismuth with chiral (1R)-(–)-camphor-10-sulfonic, (–)-menthyloxyacetic, or (R)-3-phenylbutyric acids. Enantioselective C-arylation of enolizable substrates with organobismuth reagents was carried out for the first time. Unlike iodine, sulfur, and selenium derivatives, which contain a five-membered heterocycle including the 2,2"-biphenylene fragment, phenyl-2,2"-biphenylene organobismuth analogs enter into C-arylation reactions accompanied by the selective transfer exclusively of the phenyl group to the organic substrate.     

Spectrophotometric determination of cysteine andN-acetylcysteine in pharmaceutical preparations

An accurate fast spectrophotometric method for the determination of cysteine andN-acetyl-cysteine is presented, based on the oxidation of these amino acids by ferric ions in the presence of ferrozine, whereby a violet-coloured complex is formed which absorbs at 562 nm. The method was satisfactory for the determination of cysteine andN-acetylcysteine in samples within the range 0.02–6.00 gml^–1. Effects of time, acidity, ferric ions, ferrozine, sodium perchlorate concentrations and the tolerance limit for other amino acids have been reported. The method was applied to the determination of cysteine in amino acids mixtures andN-acetylcysteine in pharmaceutical preparations.     

Fatty-acid composition of two <Emphasis Type="Italic">Limonium</Emphasis> plant species

The fatty-acid composition of two Limonium plant species (Plumbaginaceae), including both saturated and polyunsaturated acids, was determined for the first time using chromatography—mass-spectrometry. High contents of palmitic, oleic, linolenic, and linoleic acids were found. Methyl esters of fatty acids in Limonium Popovii were identified by mass spectrometry as hexadecanedioic, eicosanedioic, and docosanedioic acids.Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 344–346, September–October, 2004.     

Fabrication of a novel Li<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>MoO<Subscript><Emphasis Type="Italic">y</Emphasis></Subscript> film modified electrode and its application as an electrochemical sensor of iodate

A novel organic gel film modified electrode was simply and conveniently fabricated by casting Li_xMoO_y and polypropylene carbonate (PPC) onto the surface of a gold electrode. The cyclic voltammetry and amperometry studies demonstrated that the Li_xMoO_y film modified electrode has a high stability and a good electrocatalytic activity for the reduction of iodate. In amperometry, a good linear relationship between the steady current and the concentration of iodate was obtained in the range from 3×10^–7 to 1×10^–4 mol L^–1 with a correlation coefficient of 0.9997 and a detection limit of 1×10^–7 mol L^–1.     

EPR and IR spectral investigations on some leafy vegetables of Indian origin

EPR spectral investigations have been carried out on four edible leafy vegetables of India, which are used as dietary component in day to day life. In Rumex vesicarius leaf sample, EPR spectral investigations at different temperatures indicate the presence of anti-ferromagnetically coupled Mn(IV)–Mn(IV) complexes. EPR spectra of Trigonella foenum graecum show the presence of Mn ions in multivalent state and Fe³⁺ ions in rhombic symmetry. EPR spectra of Basella rubra indicate the presence of Mn(IV)–O–Mn(IV) type complexes. The EPR spectra of Basella rubra have been studied at different temperatures. It is found that the spin population for the resonance signal at g = 2.06 obeys the Boltzmann distribution law. The EPR spectra of Moringa oliefera leaves show the presence of Mn²⁺ ions. Radiation induced changes in free radical of this sample have also been studied. The FT-IR spectra of Basella rubra and Moringa oliefera leaves show the evidences for the protein matrix bands and those corresponding to carboxylic CO bonds.     

Spectral studies on the reaction of chromium (VI) compounds with aminophosphonic esters

The studies on reaction of newly obtained aminophosphonic acid diethyl ester derivatives of fluorene with Cr₂O₇ ^2–, CrO₄ ^2–, CrO₃Cl^– and CrO₃ have been investigated using electronic, infrared,Raman and NMR spectral methods. It has been found that the resulting compounds are of the type (AH)₂Cr₂O₇, whereA stands for the organic part of the molecule. The organic cation and solvent effects on the electronic states of pseudotetrahedrally arranged Cr(VI) anions are discussed.

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Spektroskopische Untersuchungen über Reaktionen von Chrom(VI)-Verbindungen mit Aminophosphonsäure-Estern

Zusammenfassung Es wurden Elektronen-, Ultrarot-,Raman- und NMR-spektroskopische Untersuchungen beschrieben, die an neuen Verbindungen durchgeführt wurden, welche als Reaktionsprodukte von Cr₂O₇ ^2–, CrO₄ ^2–, CrO₃Cl^– und CrO₃ mit Aminophosphonsäurediethylesterderivaten von Fluorene synthetisiert worden waren. Es wurde festgestellt, daß diese Verbindungen mit einer allgemeinen Formel (AH)₂Cr₂O₇ beschrieben können werden, in derA den organischen Teil der Verbindungen bedeutet. Der Einfluß des organischen Kations wie auch der von Lösungsmitteln auf die Elektronenzustände des pseudotetraedrischen Cr(VI)-Anions wurde gleichfalls untersucht.

     

Electrochemical properties of polyaniline in p-toluene sulfonic acid solution

Polyaniline was deposited potentiodynamically on a stainless steel substrate in the presence of an inorganic acids (sulfuric acid). The electrochemical characterization of the electrode was carried out by means of cyclic voltammetry and electrochemical impedance spectroscopy in the organic acids (p-toluene sulfonic acid) solution. The results show that polyaniline has a high specific capacitance of 431.8 F g⁻¹ at 1 mV s⁻¹, high coulombic efficiency of 95.6% at 20 mV s⁻¹, and exhibits a high reversibility. This indicates the promising feasibility of the polyaniline used as an electrochemical capacitor material in the electrolyte of p-toluene sulfonic acid solution especially at high charge–discharge process.     

Mittlere Schwingungsamplituden der Hexachloro- und Hexabromo-Anionen einiger Lanthanide

Mean amplitudes of vibration for various octahedral complex compounds of the typeLnCl₆ ^3– andLnBr₆ ^3– (withLn=Nd, Eu, Gd, Dy, Er, and Yb) have been calculated, at different temperatures, using known spectroscopic data. The results are briefly discussed and it is found that theLn–Cl andLn–Br amplitude values are highly characteristic.

     

Acid-base and complexation properties of <Emphasis Type="Italic">gem</Emphasis>-diphosphonic and <Emphasis Type="Italic">gem</Emphasis>-diphosphinic acids in aqueous solutions and micellar media of surfactants

Acid-base and complexation properties of gem-disubstituted phosphorus acids, viz., methylenediphosphonic, 1-hydroxyethylidene-1,1-diphosphonic, P,P-diphenylmethylene-diphosphinic, and P, P-diphenyl-1-hydroxyethylidene-1, 1-diphosphinic acids, were studied in aqueous solutions and in the presence of biomimetics (micelles of ionic surfactants). The dissociation constants of the acids and stability constants of complexes with magnesium(II) and copper(II) ions were determined in aqueous solutions and microheterogeneous media containing sodium dodecyl sulfate, cetylpyridinium chloride, or cetylpyridinium nitrate (ionic strength 0.1 mol L^–1, temperature 25°C).Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1919–1925, September, 2004.     

Uronic (hexenuronic) acid profile of ethanol–alkali delignification of giant reed Arundo donax L.

The effect of process variables on uronic acids (UAs) and hexenuronic acids (HexAs) in the annual crop Arundo donax L. during ethanol–alkali pulping has been examined. A substantial loss of UA moieties (up to 90%) was observed by the end of pulping (target kappa number 18) performed with 25% NaOH and 40% EtOH (by volume) within the temperature range of 130–150 °C. At the same time, the progressive formation of HexA in pulp was detected from the early phases of delignification. The proportion of HexA in the residual UA of the final pulp was found to be 84%, indicating almost complete conversion of 4-O-methylglucuronic acid side groups (MeGlcA) of heteroxylan into HexA. The kinetics of UA degradation and HexA formation has been described in terms of three consecutive first-order reaction stages. The overall rate of UA degradation was one order higher than the rate of UA conversion into HexA. The values of apparent activation energy were estimated as 68.6 and 94.7 kJ mol^–1, respectively. The reaction medium alkalinity was shown to be the controlling factor for UA and HexA stability during ethanol–alkali pulping. An increase in alkali charge from 5% to 35% (as NaOH) led to UA loss of 40%, but promoted HexA formation from 11.8 to 20.1 mol g^–1. The addition of organic solvent to the alkaline pulping solution had a similar effect, and about 10% of UA was lost and the content of HexA increased from 6.9 to 10.9 mol g^–1 with an increase in ethanol proportion in the liquor from 20% to 60%.     

A Rapid Densitometric Method for the Quantification of Luteolin in Medicinal Plants Using HPTLC

Luteolin, a flavonoid, is reported to occur widely in many medicinal plants. It has been shown to have important biological activities. We report sensitive HPTLC method for the quantification of luteolin from plant material. The method was validated for precision, repeatability and accuracy. The method was found to be precise with RSDs for intraday in the range of 0.77–1.29% and inter–day in the range of 1.02–2.08%. Instrumental precision and repeatability of the method were found to be 0.39 and 0.57 (%CV). Accuracy of the method was checked by recovery study conducted at two different levels and the average percentage recovery was found to be 100.92%. The method was used for quantification of luteolin in three important herbal drugs viz. fruit of Cuminum cyminum, whole plant of Bacopa monnieri, flower of Achillea millefolium. The proposed HPTLC method for the quantification of luteolin was found to be simple, precise, specific, sensitive and accurate and can be used for quality control of raw materials.Revised: 1 October 2003 and 18 February 2004     

Catalytic asymmetric synthesis of polysubstituted cyclohexa-1,3-dienes from β-branched α,β-alkenals

3-Methyl- and 3-phenylbut-2-enal in the presence of (S)-prolinol (0.1 eq.) in benzene or THF react with the acidic monoesters of alkenylidene, and arylmethylidene-, and alkylidenemalonic acids at –10 to +22 °C to give optically active esters of 4,6-disubstituted cyclohexa-1,3-diene-l-carboxylic acids in moderate (10–43 %) yields. The enantiomeric purity of the products formed from the lint two types of acidic ylidenemalonates varies from 28 to 68 % and is higher than that observed in the case of related alkylidenemalonates. Under similar conditions cyclohexylideneacetaldehyde affords optically active derivatives of 1,5,6,7,8,8a-hexahydronaphthalene as mixtures ofcis andtrans isomers. The enantiomeric purity and absolute configuration of the cyclohexadienes thus obtained were determined using¹H NMR spectroscopy in combination with chiral solvating agents.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 663–669, March, 1996.