Untersuchungen über die Biosynthese der Cyclite, 17. Mitt.: Bildung vond-bornesit und Dambonit inNerium oleander

Zusammenfassung Dambonit (1,3-Di-O-methyl-myo-inosit) entsteht inNerium oleander, wie durch Einbauversuche mit radioaktiv markiertemmyo-Inosit undd-Bornesit sowie durch Bestimmung der Zeitabhängigkeit der Bildung der Cyclite bei Assimilation von¹⁴CO₂ nachgewiesen wurde, ausmyo-Inosit überd-Bornesit als Zwischenprodukt. Neben Dambonit finden sich in der Cyclitfraktion vonN. oleander auchd-Bornesit,myo-Inosit sowiel-Leucanthemit.myo-Inosit unterliegt in der Pflanze-besonders im Winter-einem sehr intensiven Stoffwechsel, der zu nichtzyklischen Verbindungen führt.

---

InNerium oleander dambonitol (1,3-Di-O-methyl-myo-inositol) is formed frommyo-inositol withd-bornesitol as intermediate, as could be shown with the help of incorporation experiments with radioactively labelledmyo-inositol andd-bornesitol and also by the determination of the time dependence of the formation of the cyclitols from¹⁴CO₂ in photoassimilation experiments. Besides dambonitol the cyclitol fraction ofN. oleander contains alsod-bornesitol,myo-inositol andl-leucanthemitol. Especially in wintermyo-inositol undergoes a very active catabolism in the plant which leads to the formation of non-cyclic compounds.

---

---

H. Kindl undO. Hoffmann-Ostenhof, Mh. Chem.97, 1771 (1966).     

l-Leucanthemit als Inhaltsstoff von Gymnospermae

Zusammenfassung Die Bildung und das Vorkommen von Cycliten inThuja occidentalis wurden mit Hilfe der Methode der Photoassimilation in einer Atmosphäre von¹⁴CO₂ untersucht. Nebenmyo-Inosit, Sequoyit,d-chiro-Inosit undd-Pinit wurde auchl-Leucanthemit (l-1,2,4/3-Cyclohexentetrol), ein Cyclit, der bisher nur als Inhaltsstoff mehrerer Angiospermae bekannt ist, nachgewiesen. Das Vorkommen vonl-Leucanthemit konnte auch inPinus austriaca sichergestellt werden. Methoden zur Isolierung vonl-Leucanthemit ausThuja occidentalis wurden ausgearbeitet.

---

The formation and the occurrence of cyclitols inThuja occidentalis has been studied, using the method of photoassimilation in an atmosphere of¹⁴CO₂. Besidesmyo-inositol, sequoyitol,d-chiro-inositol, andd-pinitol, alsol-leucanthemitol (l-1,2,4/3-cyclohexentetrol), a cyclitol which so far has only been found in Angiospermae, was identified. The occurrence ofl-leucanthemitol could also be established inPinus austriaca. Methods have been elaborated which permit the isolation ofl-leucanthemitol fromThuja occidentalis.

     

Spectrophotometric determination of cadmium with uramyldiacetic acid

A procedure for the determination of cadmium(II) by uv spectrophotometry is proposed. This metal reacts at pH 6 with uramyldiacetic acid (UDA) to give a complex with a maximal absorbance at 265 nm and follows Beer's law in the range 0.12–3.6 μg Cd(II)/ml, the optimal interval being from 0.6 to 3.3 μg Cd(II)/ml. The sensitivity is 0.011 μg cm^?2. Through this study the stoichiometry of the chelate compound, interfering elements, and the reproducibility of the method were evaluated. The method has been applied to the determination of cadmium in biological samples and a white metal.     

Zur Biosynthese der Benzoesäuren

Zusammenfassung Es wird über die Biosynthese natürlich vorkommender Benzoesäuren aus Zimtsäuren berichtet. Der Abbau von Ferulasäure zu Vanillinsäure und der Übergang von Zimtsäure zu Gentisinsäure wird unter Anwendung¹⁴C-markierter Vorstufen beiHydrangea macrophylla, Astilbe chinensis undSinapis alba genauer untersucht.     

Determination of arsenic in mussels by slurry sampling and electrothermal atomic absorption spectrometry (ETAAS)

A method for the determination of arsenic in slurries of mussel tissue using palladium-magnesium nitrate as modifier was optimized. The slurry was stabilized by a 0.015% (v/v) of Triton X-100. To achieve complete mineralization the slurries were ashed at 480 °C for 10s in an air flow (50 ml/min) and at 1200 °C for 15s in an argon flow (300 ml/min) in the presence of Pd—Mg(NO₃)₂ as modifier. The optimum atomization temperature was 2200 °C. The precision and accuracy of the method were studied using the Reference Material BCR n ° 278 Mussel Tissue (Mytilus edulis). The detection limit (LOD) of the final slurry solution was 1 g/l of arsenic corresponding to an arsenic level in the mussel of 1.3 g/g, for a 0.5% (m/v) slurry. Results of calibration using aqueous standards and the standard additions method were compared. The method was applied to the determination of arsenic in mussels from the Galician coast. The levels found lie between 2 and 9.3 g/g of arsenic.     

Synthesis, characterization, biocide and toxicological activities of di-n-butyl- and diphenyl-tin(IV)-salicyliden-beta-amino alcohol derivatives

The one pot reaction of salicylaldehyde 1, beta-amino alcohols 2a-2c, and di-n-butyltin(IV) oxide 3a or diphenyltin(IV) oxide 3b produced five diorganotin(IV) compounds, 4a-4c, 5a, and 5c, in good yields. All compounds were characterized by IR, (1)H, (13)C, and (119)Sn NMR spectroscopy, and elemental analysis; furthermore, compounds 4b, 4c, 5a, and 5c were characterized by X-ray diffraction analysis. After the structural characterization, all of the compounds were tested in vitro against Bacillus subtilis (Gram-positive, strain ATCC 6633), Escherichia coli (Gram-negative, strain DH5alpha), Pseudomonas aeruginosa (Gram-negative, strain BH3), Desulfovibrio longus (strain DSM 6739), and Desulfomicrobium aspheronum (strain DSM 5918) to assess their antimicrobial activity. Compounds 4 and 5 demonstrated a wide range of bactericidal activities against the tested aerobic (one Gram-positive and two Gram-negative subtypes) and anaerobic bacteria (two sulfate-reducing bacteria, SRB). Compound 5 had better bactericidal performances than compound 4. For all of the compounds, the acute toxicity was measured using luminescent bacteria toxicity (LBT-Microtox) tests to track their further environmental impact. According to these results and in order to fulfill environmental regulations, the toxicity of the compounds studied herein can be modulated through the proper selection of the disubstituted tin(IV) moiety.     

Spectrophotometric determination of vanadium(V) with oxine in isoamyl alcohol

A new method for the spectrophotometric determination of vanadium(V) with 8-hydroxyquinoline in isoamyl alcohol is described. The spectra show broad absorption maxima between 450 and 490 nm. The effects of amount of reagent, acidity, time, and temperature were also studied. The optimal interval of Beer's law application is 0.75–3.50 μg vanadium/ml. The nature of the complex in solutions, as well as the interference, reproducibility, and precision of the method, was investigated. The method has been applied to the determination of vanadium in foods.     

On the trapping of positrons in cadmium in the temperature range from 80 to 330 K

The positron lifetime was measured in cadmium in the temperature range between 80 K and 500 K. For the first time a plateau was observed by this method in polycrystalline samples. The obtained data are well explained by depletion of shallow traps forT180 K and by self-trapping in the prevacancy region.     

Comparative study on the determination of cephalexin in its dosage forms by spectrophotometry and HPLC with UV-vis detection

This paper discusses the spectrophotometric determination of cephalexin as the intact cephalexin or as its acid-induced degradation product. Cephalexin can be determined in the range 1 × 10^–5–18 × 10^–5 M with relative standard deviations of 5-1%. The limits of quantitation and detection were 10^–5 and 0.3 × 10^–5 M, respectively. These procedures were compared with reversed-phase HPLC determination. No interference was observed in the presence of common pharmaceutical adjuvants. The H-point standard additions method was applied in order to correct for the possible presence of the cephalexin precursor, 7-aminocephalosporanic acid; this improves the selectivity of the UV-vis spectrophotometric method.     

Application of ultrasound-assisted acid leaching procedures for major and trace elements determination in edible seaweed by inductively coupled plasma-optical emission spectrometry

A new method using diluted reagents (nitric and hydrochloric acids and oxygen peroxide) and ultrasound energy to assist metals acid leaching with from edible seaweed was optimized. The method uses a first sonication at high temperature with hydrochloric acid as a previous stage to an ultrasound-assisted acid leaching with 7 ml of an acid solution containing nitric acid, hydrochloric acid and hydrogen peroxide at concentrations of 3.7, 3.0 and 3.0 M, respectively. Optimum conditions for the first sonication step were ultrasound energy at 17 kHz, sonication temperature at 65 °C, an acid volume of 2 ml, an hydrochloric acid concentration of 6.0 M and a sonication time of 10 min. It has been found that the first sonication stage at high temperature with hydrochloric acid is necessary to obtain quantitative recoveries for As, Ba, Fe and V. Otherwise quantitative recoveries were reached for the other elements investigated (Ca, K, Na, Mg, Cd, Cr, Cu, Mn, Ni, Pb and Zn). The repeatability of the ultrasound-assisted acid leaching method was around 10% for all elements. Adequate limit of detection and limit of quantification were reached by using inductively coupled plasma-optical emission spectrometry (ICP-OES) for measurements. The method resulted accurate after analysing several seaweed certified reference materials (IAEA-140/TM, NIES-03 and NIES-09). The method was finally applied to the multi-element determination in edible seaweed samples.