bluuebunny/crossref_metadata_2025 huggingface dataset:
Photochemische Reaktionen. 26. Mitteilung. Zur UV.‐Bestrahlung von O‐Acety1‐1‐dehydro‐2‐methyl‐testosteron. (Vorläufige Mitteilung)
Authors: Ganter C. , Greuter F. , Kägi D. , Schaffner K. , Jeger O.
Published: December 2004

The ultra‐violet irradiation of O‐acetyl‐1‐dehydro‐2‐methyl‐testosterone (1) in dioxane solution leads to a mixture of ketonic and phenolic isomers from which five components (2–6) have been isolated. The structures of ketones 2 and 4 have been established. The sequence of photochemical rearrangements is1→2→3. Evidence points to the intermedi acyof an isomer of type e and the formation of compounds 4 and 5 from 3. Structural formulas for 3 (=g) and 5 (=j) are advanced on this basis. The close relationship between the sequences of rearrangements initiated by the irradiation of O‐acetyl‐1‐dehydro‐testosterone and its 2‐methyl homologue (1), respectively, is discussed.
Die Biosynthese des Digitoxigenins, Herkunft des C‐20. Glykoside und Aglykone, 253. Mitteilung
Authors: v. Euw J. , Reichstein T.
Published: December 2004

Mevalonic‐[3‐14C] acid (Ia) has been prepared by partial reduction of β‐hydroxy‐β‐methyl‐glutari‐[3‐14C] acid. After introduction of the ammonium salt of Ia into Digitalis lanata plants by the vick technique, crist. radioactive digitoxigenin was isolated. This contained a significant amount of radioactivity in C‐20 position. From this, together with results of former authors, it follows that the biosynthesis of digitoxigenin from mevalonic acid (probably via squalene) proceeds through a pregnane derivative. The latter needs only one molecule of acetate to form the butenolide ring.
Etude de l'évolution duméthyl‐2‐pentène‐2‐al et de l'éthyl‐2‐hexène‐2‐al en milieu aqueux alcalin à température élevée
Authors: Blanc Pierre Yves , Perret Adrien , Teppa Franco
Published: December 2004

L'ensemble de nos résultats donne une image à peu prés complété de l'action de solutions aqueuses alcalines à env. 200° sur le méthyl‐2‐pentène‐2‐a1 et l'éthyl‐2‐hexène‐2‐al, qui grâce à la ramification de leur squelette carbonique en α, résistent à la résinification. II met clairement en évidence le rôle important de l'alcalinité dans leur évolution et la différence fondamentale de leur comportement par rapport à celui des aldéhydes non ramifiés ou saturés. En outre, nos recherches montrent que l'allongement de chaîne des aldéhydes tels que le propanal et le butanal, se fait par une voie qui n‵ést pas la méme A 200° qu'à 100°. A température peu élevé, c'est l'aldolisation multiple et linéaire de plusieurs molécules d'aldehyde initial qui est la rkgle [25].
Weitere Reaktionen an Acylchinonen und verwandten Verbindungen
Authors: Bosshard P. , Fumagalli S. , Good R. , Trueb W. , v. Philipsborn W. , Eugster C. H.
Published: December 2004

Es werden die Synthesen von 3‐Acetyl‐5‐methoxy‐naphtochinon und 3‐Carb‐äthoxy‐5‐methoxy‐naphtochinon sowie deren Furanadditionsprodukte beschrieben. Nur das aktive 3,4‐Dimethoxyfuran addierte sich in nichtkatalysierter Reaktion. Es ist möglich, die Addition rnit Hilfe einer LEWIS‐Säure (z. B. ZnC12) zu fördern.
Structure de la carbamoyl‐benzamidoxime
Authors: Buyle R. , Lenaers R. , Eloy F.
Published: December 2004

Benzamidoxime and cyanic acid react to give O‐carbamoyl‐benzamidoxime, and not the oxime of benzoylurea as generally admitted. 3‐Phenyl‐5‐hydroxy‐l,2,4‐oxa‐diazole is quantitatively formed by reacting hydroxylamine on carbamoylbenzami‐dine.
Metallionen‐Katalyse bei der H2O2‐ bzw. Radikalbildung durch autoxydable Cytostatica
Authors: Erlenmeyer H. , Zell R. , Brintzinger H. , Prijs B.
Published: December 2004

The formation of H2O2 during autoxydation of certain cytostatic agents like α‐aminoketones and methylhydrazine derivatives is shown to depend on the presence of metal ions. The biochemical implications of this finding, e.g. for the development of cytostatic tumor therapy and of appropriate tests are discussed.
Die Cardenolide der Samen von Strophanthus vanderijstii Staner. 3. Mitteilung. Identifizierung und Konstitutionsermittlung der wasserlöslichen Glykoside. Glykoside und Aglykone, 255, Mitteilung
Authors: Bernneisen K. , v. Euw J. , Tamm Ch. , Reichstein T.
Published: December 2004

Five crystalline cardenolides (G, H, K, M1 and O‐acetyl‐M1) isolated from the seeds of Strophanthids vanderijstii could be identified with known glycosides. Probable structural formulae, based on results of enzymatic and chemical hydrolysis, were suggested for seven new cardenolides (M4, M5 O, P2 Q1 Q2 and Q3). Trivial names were given to two other new crystalline compounds, callengoside (J) and kisantoside (L1), which seem to be components characteristic of S. vanderijstii. Their structure is still unknown, each may contain a new genin. Both contain digitalose, and kisan‐toside perhaps an additional unit of hexose.
Dosage ampérométrique rapide, en une seule opération et sans séparation, du calcium et du magnésium dans le sérum sanguin et dans l'urine
Authors: Monnier D. , Rouèche A.
Published: December 2004

Un dosage ampérométrique simple (réalisé en une seule opération) et trés rapide (25°) du Ca et de Mg dans le sérum, l'urine et les calculs est proposé. Le calcium est dosé par l'ion éthylheglycol‐bis‐(amino‐2‐éthyléther)‐N, N′‐tétracétate, et le magnésium, par l'ion éthyEnediamine‐tétracétate en présence d'un tampon (pH =10,5)et d'un complexant (citrate‐tartrate). Les courbes de polarisation montrent que le mercure est oxydé à 20 mV en présence d'EGTA ou d'EDTA. Le courant qui semanifeste dans ces conditions marque la fin des titrations. La précision est de ± 2,5%pour le Ca et ± 5,0% pour le Mg. Dans le cas de l'urine un traitement oxydant préalable est nécessaire (minéralisation complète ou traitement au KMnO4). La précision est de ± 5,0% pour les deux éléments.
Methylvinylfulvene
Authors: Neuenschwander M. , Meuche Doris , Schaltegger H.
Published: December 2004

6‐ [l‐propenyl]‐fulvene (11), 6‐isopropenyl‐fulvene (111) and 6‐methyl‐vinyl‐ fulvene (IV) have been prepared by condensation of cyclopentadiene with trans‐ crotonaldehyde, methacrolein and methyl vinyl ketone, using sodium ethylate as base. The UV.‐, 1R.‐ and NMR.‐spectra have been investigated.
Weitere Alkaloide aus den Blättern von Pleiocarpa tubicina; Umwandlung von (—)‐Quebrachamin in (+)‐1,2‐Dehydroaspido‐spermidin 6. Mitteilung über Pleiocarpa‐Alkaloide [1]
Authors: Bycroft B. W. , Schumann D. , Patel M. B. , Schmid H.
Published: December 2004

From the leaves of Pleiocarpa tubicina STAPF (+)‐Quebrachamine ((+)‐I), (−)‐1,2‐Dehydroaspidospermidine (( −)‐II), and (−)‐Aspidofractinine (IV), have been isolated in small quantities. The interesting conversion of (−)‐Quebrachamine ((−)‐I) into(+)‐1,2‐Dehydroaspidospemidine ((+)‐II) has been achieved by controlled per‐manganate oxidation.
Propriétés et structure de la cétolactone C12H16O3 de l'essence de Jasmin (Jasminum grandiflorum L.)
Authors: Demole E. , Willhalm B. , Stoll M.
Published: December 2004

The ketolactone C12H16O3 discovered by NAVES & GRAMPOLOFF [3] in 1942 in an Italian jasmine oil is shown to be the lactone IV of 2‐(5‐hydroxy‐cis‐pent‐2‐enyl)‐3‐oxo‐cyclopentylacetic or 5′‐hydroxy‐jasmonic acid (V ). Contrary to the findings of NAVES & GRAMPOLOFF, this hydroxy‐acid does not lactonize spontaneously, and the ketolactone IV has no odour.
Dibenzo‐azepine, ‐diazepine, ‐Oxazepine und ‐thiazepine. 3. Mitteilung über siebengliedrige Heterocyclen
Authors: Hunziker F. , Künzle F. , Schindler O. , Schmutz J.
Published: December 2004

An examination of the BISCHLER‐NAPIERALSKI reaction starting with 2‐acylamino‐diphenyl‐amines, ‐sulfides, ‐methanes, and ethers, resp., is reported. Using phosphorous oxychloride or polyphosphoric acid, the products are azomethine derivatives of 5H‐dibenzo[b, e]‐1,4‐diazepines, dibenzo[b, f]‐l,4‐thiazepines, llH‐dibenzo[b, e]‐azepines resp. dibenzo[b, f]‐l, 4‐oxazepines having the general formula III. The azomethine bridge in III can be hydrogenated catalytically or reduced with LiAlH4, to give derivatives of the general formula VI. Using several dialkylaminoalkyl chlorides in the presence of Na‐amide, these derivatives are alkylated to VII. The basic strengths of several derivatives of III and VI are reported and the correlation between the basicity and the heteroatom in III and VI is discussed. The thiazepine derivatives show a noticeably lowered basicity, which we could not explain either by the inductive or by mesomeric effects of the sulfur bridge‐atom.
Composés d'addition formés par le perchlorate d'argent avec des hydrocarbures aromatiques
Authors: Torre‐Mori B. G. , Janjic D. , Susz B. P.
Published: December 2004

The authors have prepared the 1 : 1 adducts between ‐AgClO4, and the hydrocarbons benzene, toluene and m‐xylene. The electronic absorption spectra of their solutions in the corresponding hydrocarbon exhibit each an absorption band between 2770 Å and 2900 Å. The same bands are found in solutions of AgClO4,in the hydrocarbons mentioned and in mesitylene.
Über Pyrrolizidinchemie 4. Mitteilung [1]Hydrierte Derivate des 2,5‐Dioxo‐3‐phenyl‐2,3‐dihydro‐5H‐pyrrolo[2,1‐a]isoindol‐1‐carbonsäure‐äthylesters
Authors: Viscontine M. , Pfenninger H. A.
Published: December 2004

Ein Dihydroalkohol und 4 stereoisomere Tetrahydroalkohole wurden nach NaBH,‐ oder katalytischer Reduktion des 2‐Hydroxy‐3‐phenyl‐5‐oxo‐SH‐pyrrolo[2,1‐a]isoindol‐l‐carbonsäure‐athylesters erhalten, isoliert und charakterisiert.Die Konfiguration der Tetrahydroalkohole ist noch nicht abgeklart.
Die STEVENS‐Umlagerung von Allyl‐phenacyl‐ammoniumsalzen
Authors: Heffe W.
Published: December 2004

The reported new examples of the STEVENS rearrangement of allyl‐ (or crotyl‐)phenacyl‐ammonium salts confirm that the allyl (or crotyl) group migrates rather than the phenacyl group, and that the migration of the crotyl group is accompanied by a shift of the double bond analogous to the shift in an allyl rearrangement.
Methämoglobinbildung in Erythrocyten durch Peroxideinwirkung. Versuche zur Beurteilung der Schutzfunktion von Katalase und Glutathionperoxidase
Authors: Aebi H. , Heiniger J. P. , Lauber E.
Published: December 2004

The rate of methaemoglobin formation induced by small amounts of H2O2, a) generated enzymatically, or (b) added by diffusion as vapour, has been investigated in suspensions of normal and acatalasic red cells.

At low rates of H2O2‐generation (i.e. 10−10−10−9 moles H2O2/mg Hgb/min) removal of H2O2 is mainly due to glutathione peroxidase activity, whereas at higher rates (i.e. 10−9−10−7 moles H2O2/mg Hgb/min) catalase activity is responsible for haemoglobin protection. Under the latter experimental conditions the yield of methaemoglobin formcd depends mainly on red cell catalase activity.

The existence of a lag‐phase in methaemoglobin formation and measurements of reduced glutathione concentration suggest that catalase and haemoglobin compete for excess H2O2 only after the intracellular supply of reduced glutathione has been exhausted and the H2O2 concentration in the cells has passed a critical level of than 7 · 10−6MH2O2.
«Tripeldecker‐Sandwiches» aus Ferrocen und Nickelocen
Authors: Schumacher Ernst , Taubenest Richard
Published: December 2004

A mass‐spectrometric study of ferrocene and nickelocene revealed considerable intensities of ion‐molecule associates, e.g. Fe2Cp3⊕, Ni2Cp3⊕, and FeNiCp3⊕, which have not been found in an earlier investigation [l]. It is proposed that these particles represent tripel‐decker sandwiches.
Über die isomeren Dikobaltoctacarbonyle. III [1]. Infrarotspektren von Dikobaltoctacarbonyl, Quecksilber‐ und Cadmiumkobalcarbonyl bis 300 cm −1 und die Struktur des brückenlosen Dikobaltoctacarbonyls
Authors: Noack K.
Published: December 2004

The study of the temperature effect on the infrared absorption of dicobaltoctacarbonyl, which has led to the discovery of a non bridged isomer, has been extended to 300 cm−1. In the spectrum of the non bridged form only two bands have been found in the range from 700 to 300 cm−1, as compared with 8 for the bridged form. This is taken as further evidence that the non bridged isomer has a structure with D3d‐symmetry. For comparison the spectra of mercury and cadmium cobaltcarbonyl were also measured and found in agreement with the previously established structure.
Note sur quelques monoesters des acides chlorométhane‐, méthane‐ et benzène‐phosphoniques
Authors: Cherbuliez Emile , Čolak‐Antić Sl. , Gowhari M. , Weber G. , Rabinowitz J.
Published: December 2004

Polychloromethanephosphonic acid (a partial anhydride) is obtained by heating chloromethanephosphonic acid with its dichloride. Heated with alcohols, polychloromethanephosphonic acid yields the corresponding chloromethanephosphonic monoesters.
Reaktivität von Koordinationsverbindungen XII [1]. Einfluss verschiedener Liganden auf den Mechanismus der Cu2+‐Katalyersierten Autoxydation von o‐Phenylendiamin
Authors: Wüthrich K. , Fallab S.
Published: December 2004

The Cu2+‐catalyzed oxidation of o‐phenylenediaminc (H2B) by O2 is strongly influenced by different organic and inorgarnic ligands. While chelating agents, e. g. ethylenediamine and ethylenediamine tetraacetic acid, inhibit the catalysis by Cu2+, the reaction is accelerated under the influence of some monodentate ligands, e.g. C1−, Br−, NH3, pyridine and imidazolc (PYR). We have found that these latter ligands enable the cupric ion to react directly with H2B (I). The cuprous complex
equation image
formed in equilibrium is then reoxidized by O2 (II). The rate determining oxidation step (I) is much faster than any direct reaction between o‐phenylenediamine and O2 catalyzed by cupric ion.
Metallionen‐Katalyse bei der H2O2‐ bzw. Radikal‐Bildung durch autoxydable Cytostatica. III. Ligand‐Effekte
Authors: Brintzinger H. , Zell R. , Erlenmeyer H.
Published: December 2004

The effect of various ligands on Mn2+‐catalysed radical and H2O2, formation by autoxidation of cytostatic hydrazine derivatives has been investigated. The catalytic action is activated by ligands which favour formation of the tervalent state of manganese ion. This finding is discussed in terms of possible mechanisms.
Recherches sur la formation et la transformation des esters LIII [1] Monoesters phosphoreux d'alcools tertiaires et de phénols
Authors: Cherbuliez Emile , Prince R. , Rabinowitz J.
Published: December 2004

Phosphorous acid does not dehydrate tertiary alcohols at temperatures below 100 °C; but the esterification reaction is very slow and phosphorous monoesters of tertiary alcohols cannot be obtained this way. Although this reaction is also slow with phenol, phenyl phosphorous monoester can be obtained by heating 1 mole of phenol and 1 mole of H3PO3 4 days at 145°, with 15‐20% yield.
Was sind Elektronen??
Authors: Primas H.
Published: December 2004

Elektronen sind in der Quantenmechanik nicht‐individuelle, substanzlose Strukturen; in der klassischen Chemie sind sie dagegen individuell und lokalisiert. Es wird darauf hingewiesen, dass der mathematisch exakt definierte Begriff des Quasielektrons im Sinne der GREEN‐Funktion der modernen Quantenmechanik genau dem vom Che‐ miker intuitiv postulierten Elektronenbegriff entspricht; damit eröffnet sich die Möglichkeit einer exakten und dennoch anschaulichen Beschreibung der Molekeln. Bisher operationell nicht erklärte Probleme können damit zu echten naturwissenschaftlichen Fragen werden.
Die ESR.‐Spektren der Radikal‐Anionen des Hexamethylund des Hexaäthylradialens
Authors: Gerson F.
Published: December 2004

Radical anions formed by alkali metal reduction from hexamethyl‐ and hexa‐ethyl‐radialene in 1, 2‐dimcthoxyethane solution are found to be relatively stable at temperatures below −20°C. The ESR.‐spectra of the radical anions have been recorded and their hyperfine structures discussed.
Eine Neuaufnahme* der ESR.‐Spektren der Radikal‐Anionen symmetrisch substituierter Dimethylnaphtaline
Authors: Gerson F. , Weidmann B. , Heilbronner E.
Published: December 2004

ESR. spectra of the radical anions of the six symetrically substituted dimethyl‐naphtalenes have been recorded. The methyl proton coupling constants show a close correlation with HÜCKEL spin densities (unpaired electron densities) if the inductive effect of the methyl groups is taken into consideration.
Zur Kenntnis der sogenannten «Alkalicarbonyle» VI Über den paramagnetischen Anteil der «Alkalicarbonyle»
Authors: Büchner W. , Lucken E. A. C.
Published: December 2004

The solid compounds resulting from the reaction between carbon monoxide and potassium, either molten or dissolved in liquid ammonia, have been shown by EPR. spectroscopy to contain low concentrations of free radicals. These solids dissolve in water to give deeply coloured solutions which also display EPR. spectra. It has been shown that the radical in the product formed from molten potassium at 250°C is mainly the potassium salt of tetrahydroxybenzosemiquinone, while the product from either molten potassium at 70°C or potassium dissolved in liquid ammonia contains at least two radicals. From the measurements made on the aqueous solutions, one of these has been shown to be the potassium salt of 2,5‐dihydroxy‐1,4‐benzosemiquinone. The other radical is thermally instable and is probably a non‐linear open‐chain radical. Dihydroxybenzoquinone seems to be formed during the removal of the ammonia.
De la chimie des ptérines. 10e communication. Substitutions nucléophiles de la ptérine tétrahydrogénée par l'ammoniac, les amines primaires et les amines secondaires
Authors: Viscontini M. , Merlini L. , Nasini G. , Von Philipsborn W. , Piraux M.
Published: December 2004

Nous avons comparé les spectres UV. et RMN. de l'hydrazino‐8‐ptérine d'une part et des produits d'addition oxydative de l'ammoniac, d'amines primaires et d'amines secondaires sur la tétrahydroptérine I, d'autre part. Cette comparaison démontre avec certitude que tous les produits étudiés sont aromatiques et que les cycles hydrazines de ces substances ne sont pas hydrogénés.
Umwandlung von Krötengiften (Bufadienoliden) durch Mikroorganismen III. 12β‐Hydroxymarinobufagin. 13. Mitteilung über Reaktionen mit Mikroorganismen
Authors: Schüpbach M. , Tamm Ch.
Published: December 2004

Incubation of marinobufagin (1) with cultures of Fusarium lini (BOLLEY) gave the unknown 12β‐hydroxymarinobufagin (2). The structure of 2 was proved by the degradation of its diacetyl derivative 3 to methyl 3, 12‐dioxo‐14‐hydroxy‐Δ4‐14β, 17αH‐etianate (6) which was prepared from the known methyl 3‐oxo‐12β, 14‐dihydroxy‐Δ4‐14β, 17αH‐etianate (5).
Über Sydnonimine V Die thermische Zersetzung von 3‐Benzylsydnonimin‐Salzen
Authors: Daeniker H. U.
Published: December 2004

The decomposition of 3‐benzyl‐sydnonimine‐hydrochlorides has been investigated and a mechanism for this reaction has been proposed.
Techniques nouvelles de microspectrophotométrie infra‐rouge des solides
Authors: Baudet P. , Otten Cl. , Cherbuliez E.
Published: December 2004

Procedures are described for micro spectrophotometry in the infrared: (1) for the quantitative incorporation of micro quantities (0,0l–0,1 μmole) of substance in KBr pellets; (2) for confection of a thin layer nujol suspension of the same quantities of substance on the surface of KBr pellets.
Allyl‐para‐dienone durch direkte Allylierung von Phenolen
Authors: Barner R. , Boller A. , Borgulya J. , Herzog E. G. , von Philipsborn W. , von Planta C. , Fürst A. , Schmid H.
Published: December 2004

1. Es wird gezeigt, dass substituierte Allylbromide Phenol mehr an Kohlenstoff alkylieren als Allylbromid selbst.
Rechnerische Untersuchung des Einflusses der Assoziation auf das Redoxpotential von Küpenfarbstoffen
Authors: Milićvić B. , Veillon F.
Published: December 2004

The influence of association on the redox potential of vat dyes has been studied by means of a simple theoretical model. The calculation method used is illustrated by the information flow chart (Fig. 1), which indicates also how the program in UNIVAC‐III‐FORTRAN‐IV has been written. The results obtained are summarized in Fig. 2.
Zur Kenntnis der BOHN‐SCHMIDT'schen Reaktion. 2. Mitteilung Reaktionen des Bis‐sulfuryldioxy‐(1, 9; 4, 10)‐anthracenchinons‐(5,8)
Authors: Winkler J. , Jenny W.
Published: December 2004

Chemical reactions prove that the product of the reaction of oleum with 1,4,5,8‐tetrahydroxy‐anthraquinone is an anthracene‐5,8‐quinone. The product of the action of high‐percent oleum on this quinone is investigated by mass spectroscopy.
Recherches sur la biochimie des cyclitols IX. Contribution à l'étude du métabolisme du ms‐inositol chez le Rat II
Authors: Charollais E. , Posternak Th.
Published: December 2004

Des rats normaux et phlorizinés ont été traités par du ms‐inositol‐[U‐14C] et ‐[2‐14C]; chez le Rat normal, les radioactivités dans le CO2 expiré sont sensiblement les mêmes, ce qui implique une combustion complète de l'inositol. Chez le Rat phloriziné, il se produit une exaltation remarquable de la glucogenèse à partir de l'inositol. La radioactivité dans le CO2 expiré est alors notablement plus faible après administration d'inositol‐[2‐14C] qu'après celle d'inositol‐[U‐14C]; le rendement radioactif dans le glucose urinaire est par contre plus faible a` partir de l'inositol‐[U‐14C]. Ces faits, ainsi que les répartitions isotopiques observées dans le glucose urinaire, ont été discutés et expliquées.
Über das Problem der Ähnlichkeit in der Chemie Über spezifisch adsorbierende Silicagele III
Authors: Bartels H. , Erlenmeyer H.
Published: December 2004

A discussion of the relationship between theoretical principles of chemical similarity on one hand and empirically measurable similarity on the other suggests that specifically adsorbing silica gels represent an experimentally simple model for ‘bioisomorphism’, the similarity found in biological systems.
Über die Inhaltsstoffe von Zizyphus oenoplia MILL. 2. Mitteilung. Zur Konstitutionsermittlung des Zizyphins
Authors: Zbiral E. , Ménard E. L. , Müller J. M.
Published: December 2004

The structure I for Zizyphin (C33H49O6N5), a peptidic alkaloid isolated from the rootbark of Zizyphus oenoplia MILL., has been determined by chemical degradation and confirmed by N.M.R. investigation. The stereochemistry of Zizyphin has been elucidated with the exception of the configuration of the ether group of the hydroxyproline unit, which is expected to belong to the natural series.
Welkstoffe und Antibiotika. 34. Mitteilung. Synthese von Isojavanicin und vereinfachte. Synthese von Javanicin
Authors: Widmer E. , Meyer J. W. , Walser A. , Hardegger E.
Published: December 2004

Aus 1,2,4‐Trimethoxybenzol (I) wurde das 2‐Methyl‐3‐acetonyl‐7‐methoxynaphtazarin (Isojavanicin) (XIIe) synthetisiert, wobei als entscheidende Aufbaureaktion die Einführung des Acetonylrestes durch MICHAEL‐Addition von Acetessigsäure‐benzylester an das 2‐Methyl‐5,7,8‐trimethoxy‐1,4‐naphtochinon (VIII) erfolgte. Entgegen unseren früheren Versuchen ermöglichte die analoge Anlagerungsreaktion an 3‐Methyl‐5,7,8‐trimethoxy‐1,4‐naphtochinon (XVII) eine wesentliche Vereinfachung der Synthese des Javanicins (XXa). Erwartungsgemäss zeigten Javanicin (XXa) und Isojavanicin (XIIe) in UV., IR., NMR. und Massenspektrogramm keine oder nur geringe, strukturell noch nicht interpretierbare Unterschiede, während die Mischprobe der beiden Substanzen eine überraschend grosse Schmelzpunktdepression gab.
Photochemische Reaktionen 30. Mitteilung. Die UV.‐Bestrahlung von 3β‐Hydroxy‐11‐oxo‐lanostan
Authors: Altenburger E. , Wehrli H. , Schaffner K.
Published: December 2004

Upon irradiation of an ethanolic solution of 3β‐hydroxy‐11‐oxo‐lanostane(1) with ultraviolet light and subsequent acetylation of the crude reaction mixture, a single tertiary alcohol, the 11,18‐cyclobutanol derivative 4, could be isolated in about 40% yield (corrected for recovered starting material). According to previous findings[4] and in contrast to this result, the steroidal 4,4‐dimethyl‐ketone 15 is exclusively converted into the 11,19‐cyclobutanol 16. It is assumed that the additional methyl group in the 14α position of 1 causes this shift of the selective attack in the photo‐chemical cyclization process from CH3‐19 to CH3‐18.
Zur Thermodynamik der Metallcarbonate 1. Mitteilung. Löslichkeitskonstanten und Freie Bildungsenthalpie von Cadmiumcarbonat, ein Beitrag zur Thermodynamik des ternären Systems Cd‐H2O(l)‐CO2(g)
Authors: Gamsjäger H. , Stuber H. U. , Schindler P.
Published: December 2004

The equilibrium constant of the reaction CdCO3(s) + 2H+ = Cd2+ + H2O + CO2(g) has been determined at 25° in solutions of the constant ionic strength 3 M (Na)ClO4. With log*Kps0 = 6,47 ± 0,15 the free enthalpies of H2O, CO2(g) and Cd yield −161,17 ± 0,20 kcal for the free enthalpy of the reaction Cd(s) + C(s) + 3/2 O2(g) = CdCO3(s). A predominance diagram of the ternary system Cd − H2O(l) − CO2(g) is given.
Über Pterinchemie 12. Mitteilung. Darstellung zweier isomerer Dihydropterine
Authors: Viscontini M. , Huwyler S.
Published: December 2004

Es wurden zwei isomere Dihydropterine, nämlich das 6,7‐Diphenyl‐5,6‐dihydropterin(IV) und das 6,7‐Diphenyl‐7,8‐dihydropterin (V), dargestellt und deren Struktur bewiesen.
De la chimie des ptérines 13e communication [1], préliminaire. Sur le mécanisme d'oxydation des tétrahydroptérines en dihydroptérines à pH physiologique
Authors: Viscontini M. , Bobst A.
Published: December 2004

Par une étude cinétique de l'oxydation à l'air des tétrahydroptérines les auteurs montrent qu'après le transfert de deux électrons à l'atome d'oxygène, la ptérine se trouve sous forme d'une ptérine dihydrogénée de structure para‐quinoïdique, fort instable et se transposant rapidement en ptérine 7,8‐dihydrogénée.
Struktur der Drevogenine. Glykoside und Aglykone, 267. Mitteilung.
Authors: Sauer H. H. , Weiss Ek. , Reichstein T.
Published: December 2004

The structural formulae of the drevogenins A, B, P, and D from Dregea volubilis are deduced from chemical and physical properties of these substances as well as of their derivatives. Drevogenin D most probably is 3β,11β,12β,14β,20ζ‐pentahydroxy‐Δ5‐pregnene 1. Drevogenin P 11 is the corresponding 20‐oxo compound, the drevogenins B 17 and A 19 are the 12‐O‐acetyl and the 12‐O‐acetyl‐11‐O‐isovaleryl derivatives, respectively, of drevogenin P.
Muscimol, ein pharmakodynamisch wirksamer Stoff aus Amanita muscaria
Authors: Müller G. F. R. , Eugster C. H.
Published: December 2004

Es wird die Isolierung einer Substanz mit stark narkosepotenzierender Wirkung, des Muscimols C4H6O2N2, Smp. 155–156°, aus dem Fliegenpilz (Amanita muscaria (L. ex FR.) HOOKER) beschrieben. Die Substanz hat salzartigen Charakter (Betain). Muscimol ist kein genuiner Inhaltsstoff des Fliegenpilzes, sondern entsteht bei der Aufarbeitung aus einer labilen Vorstufe, die ähnliche pharmakologische Wirkungen aufweist. Der Nachweis dieser Verbindungen in Papierchromatogrammen und in Elektropherogrammen wird beschrieben. Sie sprechen mit Ninhydrin gelb, mit GROTE's Reagens blau an. Als empfindliches Nachweismittel für Indole auf Papierchromatogrammen wird Phenylheptatrienal eingeführt.
Über die Aldolase der Kaninchenleber: Molekulargewicht, Dissoziation in Untereinheiten. Über Aldolasen, 5. Mitteilung
Authors: Christen Ph. , Göschke H. , Leuthardt F. , Schmid A.
Published: December 2004

1. The sedimentation and diffusion coefficients of rabbit liver aldolase have been determined. The molecular weight has been calculated to be 151 000.
Synthesen in der Polymyxin‐Reihe 9. Mitteilung. Synthese von Polymyxin B1
Authors: Vogler K. , Studer R. O. , Lanz P. , Lergier W. , Böhni E.
Published: December 2004

The synthesis of the cycloheptapeptide 7α (Fig. 4) containing the α,γ‐diaminobutyric acid residues only in the L form, and its cristallization as pentaphosphate are reported. This latter substance proved to be in all respects identical with the cristalline penta‐ phosphate of natural polymyxine B1.
Organische Phosphorverbindungen XX. Zur Kenntnis der Reaktion von primären aliphatischen Phosphinen mit Schwefel und von Phenylphosphin mit rotem Selen
Authors: Maier Ludwig
Published: December 2004

Primary aliphatic phosphines yield tetraalkyl‐cyclotetraphosphine tetrasulfides when treated with sulfur in any ratio.
Zur Kenntnis der sogenannten «Alkalicarbonyle» VIII. Die Protolyse von KOCCOK
Authors: Büchner Werner
Published: December 2004

The protonolysis of potassium acetylenediolate KOCCOK has been investigated. The primary product from the reaction with anhydrous hydrogen chloride presumably is acetylenediol (I) which can be regarded as glyoxal‐dienol. It behaves however mainly as an acetylenic compound with an activated triple bond. Its tautomeric product glyoxal is formed in only negligible quantities. The main reaction is the polymerization of (I), giving rise to various aci‐reductones and hexahydroxybenzene. Together with these compounds diglykolide is also formed. All attempts to trap (I) in the form of DIELS‐ALDER‐addition products failed because of its rapid polymerization.
Salzkrykopie III. Eine verbesserte Apparatur zur Bestimmung der Depression des Umwandlungspunktes von GLAUBER‐Salz
Authors: Magyar B. , Schwarzenbach G.
Published: December 2004

A new apparatus is described which allows the determination of the depression of the transition point of Na2SO4,10H2O, due to foreign solutes, with a higher precision than attained before. An investigation of the various sources of error shows that the greatest uncertainty is caused by the slowness with which the final equilibrium between the two solid phases and the liquid phase is reached.
Salzebullioskopie: Eine neue Methode zur Bestimmung des relativen Gewichtes von Ionen
Authors: Magyar B.
Published: December 2004

The vapor pressure of a saturated salt solution (the salt acting as inert electrolyte) is lowered by foreign solutes to an amount which is proportional to the molar concentration of the foreign solute. Any ion not contained in the inert electrolyte is acting as a foreign solute. Basing on that effect, a new method for the determination of the relative weights of ions has been developed and the principle of HILL was applied thereby. Sodium chloride acted as an inert electrolyte. The method has been applied to a number of different salts (foreign solute) with good success.
NMR.‐Untersuchungen an einfachen Furenidonsystemen. Synthese des unsubstituierten Δ2‐Furenidons‐(4) («β‐Hydroxyfuran»)
Authors: Hofmann A. , v. Philipsborn W. , Eugster C. H.
Published: December 2004

The parent compound of the Δ2‐furenidones‐(4) (= «β‐hydroxyfurans») has been prepared by mild hydrolysis of β‐methoxyfuran. It is not a phenolic substance, but exists as the tautomeric α,β‐unsaturated ketone (or vinylogous lactone), as shown by UV.‐, IR.‐ and NMR.‐spectra. The synthesis of 3‐acetyl‐Δ2‐furenidone‐(4) is described and the chemical and physical properties of this compound are compared with those of isomaltol.
Isolierung von Ergosin und Ergosinin neben Agroclavin aus den Samen von Ipomoea argyrophylla VATKE (Convolvulaceae). 64. Mitteilung über Mutterkornalkaloide
Authors: Stauffacher D. , Tscherter H. , Hofmann A.
Published: December 2004

The isolation of ergosine und ergosinine as well as agroclavine from seeds of Ipomoea argyrophylla VATKE is described. This is the first case where ergot alkaloids of the peptide type have been found in higher plants.
Die Kristallstruktur der 1, 6‐Methano‐cyclodecapentaen‐2‐carbonsäure
Authors: Dobler M. , Dunitz J. D.
Published: December 2004

The crystal structure of 1, 6‐methano‐cyclodecapentaene‐2‐carboxylic acid has been determined by X‐ray analysis of three‐dimensional diffractometer intensity data. The crystals are monoclinic, a = 7.59, b = 8.75, c = 15.02 Å, γ = 108° 5′, Z = 4, space group P21/b. The structure was established by direct methods and refined by full‐matrix least‐squares analysis, using anisotropic temperature factors. The perimeter is non‐planar, with bond lengths in the range 1.38–1.42 Å, but showing small, systematic variations. The methylene bridge has CC = 1.477 Å, ∢ CCC = 99.6°; these values are discussed in terms of a simple strain energy scheme. Hydrogen bonds (2.62 Å) between pairs of carboxyl groups lead to the formation of dimers in the crystal. The arrangement of CO and COH bonds appears to be disordered.
FRIEDEL‐CRAFTS‐Reaktionen mit aromatischen äthern. 3. Mitteilung [1]. Reaktionen einiger α, β‐ungesättigter Säurechloride mit Veratrol
Authors: Marquardt F.‐H.
Published: December 2004

The reaction of veratrole with cinnamoyl chloride and with crotonoyl chloride in the presence of aluminium chloride yielded phenyl vinyl ketones. In the case of cinnamic acid, the preparation of the acid chloride as well as the FRIEDEL‐CRAFTS condensation could be carried out in one step, without isolation and purification of the chloride. Application of this procedure to acrylic acid yielded as sole product a β‐chloro‐ketone derivative, whereas with crotonic acid a mixture of the corresponding phenyl vinyl ketone and β‐chloro‐ketone was obtained. Again a different result was obtained in the condensation of methacryloyl chloride, which yielded a 1‐indanone instead of an acyclic ketone.
Inosin‐N(1)‐oxid‐Nucleotide als Komplexbildner II. Aciditätskonstanten von Inosin‐N(1)‐oxid und von dessen 5′‐Monophosphat
Authors: Sigel Helmut
Published: December 2004

A method is derived for the determination of acidity constants of ligands with two non‐identical acidic groups of similar acidity for the case of no interaction between these two groups. By this method the acidity constants of inosine‐5′‐monophosphate N(1)‐oxide are found to be pK = 5,43 and pK = 6,31. Spectrophotometric investigations show that pK belongs to the o‐hydroxy‐N‐oxide group. Therefore pK must be the acidity constant of the phosphate group. For comparison, the acidity constant of inosine N(1)‐oxide (pKA = 5,40) has also been determined.
Inosin‐N(1)‐oxid‐Nucleotide als Komplexbildner III. Komplexchemische Untersuchungen von Inosin‐N(1)‐oxid und von dessen 5′‐Monophosphat
Authors: Sigel Helmut
Published: December 2004

Stability constants of metal ion complexes, in which the metal ion is bonded to the o‐hydroxy‐N‐oxide ligand group of inosine N(1)‐oxide and inosine N(1)‐oxide 5′‐monophosphate, have been measured. The distribution of some bivalent metal ions between o‐hydroxy‐N‐oxide and phosphate ligand groups of inosine N(1)‐oxide 5′‐monophosphate has been estimated: Mn2+, Co2+, Ni2+, Cu2+, and Zn2+ are mainly bonded to the o‐hydroxy‐N‐oxide ligand group; with Mg2+, Ca2+, and Ba2+ an equilibrium between the two complexes has to be assumed.
Notiz über das ESR.‐Spektrum des Radikal‐Anions des Hexamethyl‐[3]‐radialens
Authors: Gerson F. , Heilbronner E. , Köbrich G.
Published: December 2004

The ESR.‐spectrum of the hexamethyl‐[3]‐radialene radical anion has been recorded and compared with that of the hexamethyl‐[6]‐radialene radical anion. Its hyperfine splitting pattern (coupling constant = 7,57 ± 0,08 Gauss) is in agreement with theoretical expectation and therefore supports the structure proposed for the hydrocarbon hexamethyl‐[3]‐radialene.
Die Strukturen von Erinin und Erinicin aus Hunteria umbellata
Authors: Bycroft B. W. , Hesse M. , Schmid H.
Published: December 2004

The main alkaloids Erinine and Erinicine from the leaves of the plant Hunteria umbellata (K. SCHUM.) HALL.f. have been shown on the basis of chemical and spectroscopic evidence to have the structures 1 and 2. The main arguments for the skeleton of the alkaloids rest on an interesting application of high resolution mass spectrometry for comparison of structurally similar compounds.
Die multiple Isomerisierung von Brom‐decahydroisochinolinen. Decahydroisochinoline. I. Teil
Authors: Grob C. A. , Wohl R. A.
Published: December 2004

The multiple isomerisation of 10α‐bromo‐N‐methyl‐decahydroisoquinoline (2a) is described. This compound is formed from 10β‐hydroxy‐N‐methyl‐decahydroisoquino‐line (3a) and from N‐methyl‐Δ9,10‐ and ‐Δ5,10‐octahydroisoquinoline, 4a and 5a respectively, in kinetically controlled reactions with HBr in acetic acid at 50°. At 85° the 10α‐bromide 2a is converted via the axial 5β‐trans‐bromide 8a into the equatorial 5α‐epimer 9a. At 140° an equilibrium mixture of 6β‐, 6α‐, and 7α‐trans‐bromides, 17a, 16a and 21a respectively, is obtained.
Durchflussdetektor zur kontinuierlichen Messung der molalen Konzentration gelöster Stoffe
Authors: Simon W. , Dohner R. , Clerc J. T.
Published: December 2004

A detector to measure continuously the molality of non volatile solutes in volatile solvents using vapour phase osmometry is described.
Die Überführung von (+)‐Δ3 Caren in (+)‐Δ4‐Caren
Authors: Ohloff G. , Schulte‐Elte K. H. , Giersch W.
Published: December 2004

Die Einwirkung von N‐Lithiumäthylendiamin auf (+)‐Δ3‐Caren (1) führt zu einem Gleichgewicht mit dem doppelbindungsisomeren (+)‐Δ4‐Caren (2) im Verhältnis 1:2 = 60:40.
Komplexone XXXIX. Die Bildungs‐Enthalpie und ‐Entropie der Metallkomplexe des Diäthylentriaminpentaacetat‐Ions
Authors: Anderegg G.
Published: December 2004

The enthalpy changes involved in the formation of the proton and the metal complexes of diethylenetriamine‐pentaacetate ion have been determined using a direct calorimetric method. The values obtained are compared with those of other complexons.
Sur les possibilités du dosage non destructif du fluor par activation neutronique et spectrométrie gamma du fluor‐20 ou de l'azote‐16 (périodes de resp. 10,7 et 7,35 s). Etude comparative, application à la cryolithe
Authors: Haerdi W. , Voldet P. , Monnier D.
Published: December 2004

Il a été mis au point une méthode non destructive de dosage du fluor basée sur la réaction nucléaire 19F(n,α)16N (période 16N = 7,35 s) résultant de l'activation du fluor au moyen de neutrons rapides. Avec le flux d'un réacteur du type AGN‐201‐P (2,5 · 109nth cm−2s−1), un temps de décroissance de 10 s et un temps de comptage de 6 s, on peut doser environ 5 mg de fluor; limite qui se fixerait à 0,5 μg si le flux était 104 fois plus grand.
Sur les dérivés de la fluorénone V [1] La diméthyl‐2,3 et la triméthyl‐2,3,6‐fluorénone
Authors: Chardonnens Louis , Laroche Bernard , Gamba Giacomo
Published: December 2004

Par trois exemples on montre que l'acylation du bromo‐4‐xylène‐1,2 suivant FRIEDEL‐CRAFTS se fait en position 5. Le procédé est utilisé pour la synthèse de la diméthyl‐2,3, et de la triméthyl‐2,3,6‐fluorénone, à partir desquelles les hydrocarbures correspondants ont été préparés.
Die Alkaloide aus Melodinus australis (F. MUELLER) PIERRE (Apocynaceae)
Authors: Linde Horst H. A.
Published: December 2004

Aus einem Extrakt der Stammrinde von Melodinus australis (F. MUELLER) PIERRE (Apocynaceae) wurden 15 Alkaloide isoliert. Vier von ihnen sind mit Basen bekannter Struktur identisch: Ld 64 = Condylocarpin, Ld 67 = Stemmadenin, Ld 83 = Akuammidin und Ld 84 = (−)‐Quebrachamin. Ld 86 (17) dürfte mit (+)‐17‐Methoxy‐quebrachamin identisch sein. Die Struktur von sechs weiteren Alkaloiden liess sich ganz oder teilweise ableiten und konnte immer auf das Gerüst des Kopsinins zurückgeführt werden (Ld 62 (3), Ld 63 (1) (3), Ld 65 (3), Ld 85 (8), Ld 90 (9) und Ld 91 (12)).
Quartäre Alkaloide aus Pleiocarpa mutica BENTH. 2. Mitteilung [1] über das massenspektrometrische Verhalten quartärer Stickstoffverbindungen
Authors: Khan Zaheer M. , Hesse M. , Schmid H.
Published: December 2004

Aus den Wurzeln von Pleiocarpa mutica BENTH. wurden die quartären Alkaloide Hunterburnin‐α‐methochlorid (1), Hunterburnin‐β‐methochlorid (2), Huntrabrinmethochlorid (3), Pleiocarpamin‐methochlorid (4), Kopsininsäure‐methochlorid (8) und N(a), N(b)‐Dimethylsarpaginchlorid (9) isoliert und charakterisiert.
Etude de composés d'addition des acides de LEWIS XXV [1]. Mise en évidence de la structure ionique de divers composés d'addition benzoïques et mésitoïques d'acides de LEWIS, en solution dans le chlorure de méthylène
Authors: Oulevey G. , Susz B. P.
Published: December 2004

The oxocarbonium ion [RCO]+ is shown to be present in CH2Cl2 solutions of the addition compounds between benzoic and mesitoic acid or their chlorides, and five LEWIS acids: TiCl4, AlCl3, SbCl5, SbF5 and H2SO4 (H+). In CH2Cl2 solutions of the addition compound 2,4,6‐(CH3)3‐C6H2COOH, AlCl3 the existence of the mesitoylium ion has been confirmed by infrared and ultraviolet spectra and by nuclear magnetic resonance.
Über Isoxazolidin‐3,5‐dione
Authors: Michel K. , Gerlach‐Gerber H. , Vogel Ch. , Matter M.
Published: December 2004

Es wird die Synthese von Vertretern der bisher unbekannten Isoxazolidin‐3,5‐dione durch Umsetzung von Hydroxylamin oder N‐monosubstituierten Hydroxylaminen mit substituerten Malonsäurechloriden beschrieben. Eine Anzahl der neuen Verbindungen wirken im Tierexperiment antiphlogistisch.
Polarographie an Festelektroden IV. Einfluss des Leitelektrolyten auf die submonoatomare Bleibedeckung von Silberelektroden
Authors: Schmidt E. , Gygax H. R. , Böhlen P.
Published: December 2004

Der Einfluss verschiedener wässeriger Leitelektrolyte auf die Abscheidung von submonoatomaren Bleischichten an Silberelektroden wird chronoamperometrisch mit Hilfe einer Kammerzelle untersucht, wobei die Strombilanz des Elektrodenvorganges durch coulometrische Auswertung der Chronoamperogramme kontrolliert wird.
Die absolute Konfiguration von 1‐2H1‐Äthanol
Authors: Weber H. , Seibl J. , Arigoni D.
Published: December 2004

(S)‐l‐2H1‐Ethanol (6) has been prepared in three steps from (–)‐erythro‐(2R,3S)‐3‐2H1‐butan‐2‐ol (2), itself available from cis‐butene by asymmetric hydroboration. In enzymatic tests with yeast alcohol dehydrogenase this deuterated ethanol proved to be indistinguishable from the laevorotatory isomer. This establishes the (S)‐chirality of the latter and at the same time defines the stereospecificity of the yeast alcohol dehydrogenase.
Hydrolyse und Alkoholyse von Reaktivfarbstoffen: III. Sorbitolyse von Monochlortriazin‐Farbstoffen. 3. Mitteilung über reaktionsmechanistische Untersuchungen an Reaktivfarbstoffen
Authors: Rys P. , Zollinger Hch.
Published: December 2004

The kinetics of the competitive reactions of three monochlorotriazine reactive dyes with water and with sorbitol have been investigated.

The reactions of the monochlorotriazine dyes with sorbitol anions and hydroxyl ions can be divided as follows: (a) With dyes without a NH‐group between the triazine nucleus and the other part of the molecule, the reaction follows the simple addition‐elimination mechanism (AN2E), in which the addition of the nucleophile is ratelimiting. (b) The reactions of dyes containing a NH‐group can be explained by assuming that more than one of the tautomeric isomers are reactive. With one isomer the addition of the nucleophile is the slowest step; with another the base‐catalysed decomposition of the addition complex is rate‐limiting.

The first acid dissociation constant of sorbitol is evaluated (pKa = 13.14;60°).
Propriétés physico‐chimiques et immunologiques de γG‐globulines couplées à un haptène par diazotation
Authors: Jaton J. C. , Scholer H. J. , Isliker H.
Published: December 2004

Ce travail traite des modifications physico‐chimiques et immunologiques d'anticorps, résultant de leur copulation avec un sulfonamide (Fanasil) et avec l'acide sulfanilique diazotés. La réaction de couplage permet d'introduire à volonté 1 à 70 restes d'haptène par molécule de γG‐globuline. Bien que la γG‐globuline native avant couplage soit homogène, les azo‐γG‐globulines obtenues par copulation se comportent comme des substances hétérogènes en chromatographie sur DEAE‐cellulose. Les γG‐globulines anti‐Histoplasma capsulatum, couplées au Fanasil conservent leur pouvoir de fixation à l'antigène. Cette propriété suggère la possibilité de concentrer spécifiquement une quantité appréciable de médicament sur le micro‐organisme Histoplasma..
Über die Struktur des Ascorbigens
Authors: Kiss G. , Neukom H.
Published: December 2004

Bei der Bildung des Ascorbigens aus L‐Ascorbinsäure und 3‐Hydroxymethylindol tritt eine C‐Alkylierung am C‐2 des Ascorbat‐Ions ein, wobei sich 2 diastereomere Ascorbigene bilden.
Oxydation des aldéhydes α, β‐non‐saturés par l'acide peroxoacétique
Authors: Zanesco C. R.
Published: December 2004

Die Oxydation α, β‐ungesättigter Aldehyde mit Peroxoessigsäure in Eisessig wurde untersucht.
Über die Kinetik der Reduktion von Kobalt(II)‐oxid mit Wasserstoff
Authors: Kohl Herbert Karl , Marincek Borut
Published: December 2004

An dichten Kobalt(II)‐oxidproben wurde die Sauerstoffabbaugeschwindigkeit bei Wasserstoffpartialdrucken von 70 bis 730 Torr im Gebiet von 350 bis 650°C thermogravimetrisch gemessen. Durch metallographische Untersuchung anreduzierter Proben wurde festgestellt, dass die Metallphase einen feinporigen Metallschwamm bildet. Der mittlere Porenradius wurde aus Oberflächenmessungen von vollständig reduzierten Proben auf der Basis des BET‐Verfahrens bestimmt. Die Reduktionsreaktion ist 1. Ordnung bezüglich des Reduktionsgases. Aus der Temperaturabhängigkeit der Reduktionsgeschwindigkeit ergibt sich eine Aktivierungsenergie von 11,7 ± 0,5 kcal/Mol.
Organische Phosphorverbindungen XXV Darstellung und Eigenschaften von sekundären und tertiären Phosphinsulfiden
Authors: Maier Ludwig
Published: December 2004

Two new processes for the preparation of sec. phosphine sulfides which involve reaction of dialkylamino‐dialkyl or diaryl phosphines with hydrogen sulfide, and of dialkylthionophosphonates, (RO)2P(S)H, with GRIGNARD or organolithium reagents, respectively, are described. The addition of sec. phosphine sulfides to olefins and the condensation of sec. phosphine sulfides with N‐hydroxymethyldialkylamines are reported. The conversion of tert. Phosphine sulfides to the corresponding tert. phosphine oxides is readily achieved with hydrogen peroxyde. The physical properties of several new unsymmetrical tert. phosphine sulfide and oxides are listed.
Fluoreszierende Stoffe aus Roten Waldameisen der Gattung Formica (Ins. Hym.). 4. Mitteilung. Isolierung von Isoalloxazin‐Derivaten aus Ameisenmännchen
Authors: Viscontini M. , Schmidt G. H.
Published: December 2004

Aus Männchen von Formica polyctena FOERST. wurden mit Hilfe von Chromatographie an Cellulosesäulen eine neue Riboflavinverbindung, ein Riboflavinkomplex, ein als Formicaflavin bezeichnetes tiefgelb fluoreszierendes Isoalloxazinderivat und eine weitere unbekannte, gelbgrün fluoreszierende Substanz isoliert. Die Verbindungen werden durch ihre UV.‐Spektren, Rf‐Werte sowie elektrophoretischen Beweglichkeiten charakterisiert.
Korrelation von IR.‐Absorptiosfrequenzen der Silbersalze von Carbonsäuren mit Substituentenkonstanten
Authors: Pascual C. , Simon W.
Published: December 2004

A correlation of TAFT's substituent constants σ* with the asymmetric stretching vibration of the carboxylate group of 24 silver salts of carboxylic acids shows that σ*‐values may be determined with a standard deviation of about 0.1 using IR. absorption data.
Über die Elektronenspinresonanzspektren einiger Cu2+‐Komplexe in wässeriger Lösung
Authors: Wüthrich K.
Published: December 2004

The e.s.r. spectra of aqueous solutions of Cu2+‐complexes with a series of methylpyridines (PYR) have been investigated at liquid nitrogen temperature. The experimental data indicate that the formula CU(PYR) holds for the compounds in the frozen solutions. The marked decrease of the copper hyperfine coupling constant for some of the complexes is explained in terms of a distortion of the square planar structure towards a tetrahedral environment of the Cu2+. An analogous interpretation of the e.s.r. spectra of some copper containing electron‐transfer‐oxidases, e.g. ceruloplasmin and laccase, presents a possible explanation of the experimentally observed connections between the spectra and the enzymatic activity of these compounds.
Massenspektrometrische Untersuchungen an einigen Übergangsmetallcarbonyl‐cyclopentadieniden
Authors: Schumacher Ernst , Taubenest Richard
Published: December 2004

Photographically recorded high‐resolution mass‐spectra of the dimeric cyclopentadienyl metal carbonyls of Fe, Ni and Mo and of the trinuclear (C5H5)3Ni3(CO)2 show distinct ion‐molecule associates and fragments of associates. Several of the carbonyl containing fragment ions exhibit structural dependence to some degree. Due to experimental limitations, ionisation efficiency curves allow only a rough estimation of the appearance‐potentials.