bluuebunny/crossref_metadata_2025 huggingface dataset:
Étude de composés d'addition des acides de LEWIS XXII. Échange du chlore radioactif entre AlCl3 et C6H5COCl
Authors: Oulevey G. , Susz B. P.
Published: December 2004

A method of studying the exchange of chlorine between C6H5COCl and AlCl3 labelled with 36Cl has been worked out. It consists of removing rapidly C6H5COCl from the addition compound C6H5COCl, Al[36Cl]3, formed in CS2 with p‐dioxane, which in its turn gives an addition compound p‐dioxane,AlCl3. The latter compound described by the authors is stable enough to be easily isolated and lends itself well for the measure of the radioactivity of 36Cl.
Etudes sur les matières végétales volatiles CXCV Sur les α‐ et β‐méthylcyclogéraniolènes
Authors: Naves Yves‐René
Published: December 2004

The α‐methyl‐ and β‐methylcyclogeraniolenes, isolated by vapor‐phase prepararative chromatography from the cyclisation products of dihydromyrcenes are described. Evidence, by NMR. and IR. spectroscopy, is presented for their structures. The γ‐methylcyclogeraniolene is present in the cyclisation products to a very small extent if present at all.
Über die Reaktion von dehydro‐ascorbinsäure und anderen 2,3‐Diketobutyrolactonen mit 2 Mol. o‐Phenylendiamin. 21. Mitteilung über Reduktone und Tricarbonylverbindungen
Authors: Dahn H. , Moll H.
Published: December 2004

4‐Aryl‐2,3‐diketobutyrolactone liefern in saurer Lösung mit o‐Phenylendiamin Chinoxalinlactone der Formel II, in neutralem Milieu mit 2 Mol. o‐Phenylendiamin 3‐substituierte Chinoxalin‐2‐carbonsäure‐o‐aminoanilide (VIII), Den früher beschriebenen analogen Produkten aus Dehydroascorbinsäure (I c) und 2 Mol. o‐Phenylen‐diamin kommt Formel VIIIc zu.
Struktur des Hexarhodano(II)‐di‐quecksilber(II)‐Benzol‐Komplexes
Authors: Grønbaek Rita , Dunitz J. D.
Published: December 2004

The crystal structure of the pink complex of benzene with hexa‐thiocyanato‐cobalt(II)‐dimercury(II), [CoHg2(SCN)6, C6H6], has been determined by X‐ray analysis. Layers of the composition CoHg2(SCN)6 are separated by benzene molecules. The CoII ions are coordinated octahedrally by N, the HgII ions by four S atoms in a very distorted tetrahedral arrangement in which two of the S atoms form mercury bridges, magnified image. Each benzene molecule lies between two Hg atoms, the shortest HgC distances being about 3·6 Å. The stability of the complex is discussed in terms of polarization binding between benzene and HgII.
Die Konfiguration des physiologisch wirksamen 2‐Chlor‐9‐(ω‐dimethylaminopropyliden)‐thioxanthens
Authors: Dunitz J. D. , Eser H. , Strickler P.
Published: December 2004

X‐ray crystal structure analysis of 2‐chloro‐9‐(ω‐dimethylamino‐propyliden)‐thioxanthene shows that the physiologically active, higher melting isomer (M. p. 97–98°) has the side chain in cis‐configuration to the chlorine substituent.
Alkaloid‐Studien XLIX Die Strukturen von Vallesamin und O‐Acetyl‐vallesamin
Authors: Walser A. , Djerassi Carl
Published: December 2004

The structures of two novel indole alkaloids, vallesamine and its O‐acetate, isolated from Vallesia dichotoma RUIZ et PAV, have been established as IIIa and IIIb on the basis of extensive NMR. and mass spectral measurements as well as by interconversion with apparicine (I).
Synthesen in der Isochinolinreihe Neue Synthesen der Kaktusalkaloide Anhalamin, Anhalidin, rac. Anhalonidin und rac. Pellotin
Authors: Brossi A. , Schenker F. , Leimgruber W.
Published: December 2004

The four known Cactus alkaloids anhalamine (II), anhalidine (III), rac. anhalonidine (IV) and rac pellotine (V) have been synthesized starting from mescaline (I) by new and simple procedures.
Recherches sur la formation et la transformation des esters LV. Esters d'alcools polyhalogènes avec des acides du phosphore
Authors: Cherbuliez Emile , Gowhari M. , Rabinowitz J.
Published: December 2004

2,3‐Diiodo‐allyl alcohol is prepared by adding one mole of iodine to one mole of propargyl alcohol in chloroformic solution.
Organische Phosphorverbindungen XVI. Reduktion von Phosphinsulfiden zu den entsprechenden dreiwertigen Phosphorverbindungen
Authors: Maier Ludwig
Published: December 2004

The reduction of (C6H5)3PS, (p‐CH3C6H4)3PS and (n‐C4H9)3PS with iron powder to the corresponding tertiary phosphines is described. Reduction of (o‐, p‐ClC6H4)3PS, (i‐C4H9)2P(S)H, thiophosphonic as well as thiophosphinic halides with tributylphosphine to the corresponding trivalent phosphorus compounds is also reported.
Die Konstitution von Verrucarol und Roridin C Verrucarine und Roridine, 4. Mitteilung
Authors: Gutzwiller J. , Mauli R. , Sigg H. P. , Tamm Ch.
Published: December 2004

Verrucarol (C15H22O4), the sesquiterpenoid moiety of the verrucarines and roridines, has been linked with trichodermin (2) and with trichothecolon (26). On the basis of further degradation to known fragments structure 1 is assigned to verrucarol.
Die Glykoside von Pachypodium lealii WELWITSCH und Pachypodium saundersii N. E. BR. Glykoside und Aglykone, 262. Mitteilung
Authors: Meyer U. , Weiss Ek. , Reichstein T.
Published: December 2004

Aus den succulenten Teilen von Puchypodium lealii WELWITSCH liessen sich zwei krist. Hydroxyketolactone Pacholid (Lacton A, C21H30O4) und Saunderolid (Lacton B, C20H28O4) isolieren. Sie liegen in der Pflanze als Glykoside von 2‐Desoxyzuckern vor, die sich durch milde saure Hydrolyse spalten lassen. Daneben wurden kleine Mengen von zwei weiteren Lactonen (C und C′) nachgewiesen, die nicht in reiner Form isoliert wurden. Pacholid und Saunderolid wurden als Hauptprodukte auch aus Pachypodium saundersii N. E. BR. erhalten, in kleineren Mengen wurde aus dieser Art auch ein drittes krist. Lacton, Dehydrosaunderolid (Lacton B′, C20H26O4) gewonnen. Daneben konnte auch hier in Spuren ein weiteres Lacton (C′) nachgewiesen werden, jedoch kein C.
Sur les esters activés II. Préparation et hydrolyse basique des mono‐, diet trichlor‐acétylhydrazides
Authors: Buyle R.
Published: December 2004

Using ‘activated esters’ it was possible to synthesize the hydrochlorides of mono‐, di‐ and trichloroacetylhydrazide.
Etude de quelques nouvelles Réactions fluorescentes de l'acide borique et Dosage fluorimétrique de quantités de bore de l'ordre du Nanogramme
Authors: Marcantonatos M. A. , Monnier D.
Published: December 2004

In concentrated sulfuric acid, boric acid reacted with nine substituted 2‐hydroxybenzophenones, to form fluorescent complexes. Excitation spectra indicate that these complexes are similar in structure, and fluorescence spectra show that the composition and intensity of fluorescent light depend on the electronic nature of the various substituents of the complexing agents. The optimal conditions of complex formation are investigated and the relative sensitivity of the reagents is established. All the reactants studied can be used for the determination of submicrogram quantities of boron. 2‐hydroxy‐4‐methoxy‐4′‐chloro‐benzophenone is the most sensitive reactant; it allows the determination of 0,00036 to 0,036 μg of boron (as boric acid) per ml (total volume: 3 ml) with a precision of ± 21% and ± 1,5%, respectively.
Die Cardenolide von Strophanthus gratus (WALL. et HOOK.) FRANCH. Glykoside und Aglykone, 265. Mitteilung
Authors: Jäger Horst H. , Schindler O. , Weiss Ek. , Reichstein T.
Published: December 2004

The seeds of Strophanthus gratus not only contain 4–8% ouabain but also a number of other cardenolide glycosides. The following compounds have been isolated in crystalline form: sarmentoside E, sarmentoside A, acolongifloroside K, and 5 other, probably new compounds: B, δ, η, K and λ1. Three more glycosides have been isolated in the form of their crystalline O‐acetyl‐derivatives: O‐acetyl‐sarmentoloside and two probably new compounds, ϵ1′ and ϵ2′. In addition, the presence of the four following glycosides was demonstrated by paper chromatography and further confirmed by paper chromatography after acetylation: bipindoside, sarmentoside D, tholloside and sarhamnoloside. The structures of the new compounds have not yet been investigated.
Synthese und pharmakologische Wirkung einiger dem Sedridin verwandter Derivate
Authors: Büchi J. , Broger W. , Schmidt G.
Published: December 2004

In systematischer Abänderung der Sedridin‐Molekel am heterocyclischen Ring, am Stickstoff, an der Hydroxylgruppe und an einer der Methylgruppen wurden 20 neue Derivate synthetisiert.
Die Struktur des Blattfarbstoffes Cordeauxia‐Chinon
Authors: Fehlmann M. , Niggli A.
Published: December 2004

The crystal structure determination of cordeauxia‐quinone C14H12O7 [1] (space group P1) has settled the relative positions of the substituents at the naphthazarine skeleton. Furthermore, the bond lengths seem to favour the tautomeric form of formula IV. The acetyl and methoxyl groups deviate significantly from the planarity of naphthazarine; by intermolecular hydrogen bonds between hydroxyl and acetyl groups of adjacent molecules, infinite chains are formed.
Umwandlung eines Betacyans in ein Betaxanthin Synthese von Indicaxanthin aus Betanin
Authors: Wyler H. , Wilcox M. E. , Dreiding André S.
Published: December 2004

When betanin (III) was treated with S‐proline (IV), a base exchange took place which produced indicaxanthin (I). In this way this yellow pigment of the cactus fruit was partially synthesized by a method which should be generally applicable for the mutual interconversion of betacyanins and betaxanthins. For it was also possible to transform indicaxanthin into betanidin (II) by a base exchange with 5,6‐dihydroxy‐2,3‐dihydroindole‐2S‐carboxylic acid (V).
Die Einwirkung von Chlor und Brom auf die Oxymercurierungsprodukte des Norbornens
Authors: Tobler Erich , Foster Donald J.
Published: December 2004

The action of bromine on the hydroxymercuration product of norbornene in chloroform results in the cleavage of the carbon‐mercury bond to give a mixture of 2‐exo‐bromo‐3‐exo‐hydroxynorbornane and its endo‐bromo isomer. If the reaction medium is pyridine, the formation of 2,3‐exo‐epoxynorbornane is observed in addition to the bromohydrins.
Zur Kenntnis der Hexaalkylbenzole. 6. Mitteilung. Hexa‐n‐propyl‐benzol und Hexaisopropylbenzol
Authors: Hopff H. , Gati A.
Published: December 2004

The constitution of hexa‐(n‐propyl)‐benzene, which is the sole crystalline product of the aluminium chloride catalysed FRIEDEL‐CRAFTS reaction between n‐propyl chloride and benzene or n‐propylbenzenes, has been proved by its synthesis through the trimerisation of di‐(n‐propyl)‐acetylene.
Lösungsmittel‐sensibilisierte strahlungschemische Reaktionen. I. Umlagerungsreaktionen von konjugierten ungesättigten Steroidketonen
Authors: Hoigné J. , Schaffner K. , Wenger R.
Published: December 2004

The unsaturated steroidal ketones 1 and 2 undergo rearrangements upon γ‐irradiation in liquid solution in the presence of aromatic sensitizers. The G‐values in benzene solution are about 2, with only a small concentration dependence in the range 0.015–0.39 mole/liter: τ (lifetime of benzene‐excitation) multiplied by k3 (reaction rate constant for energy transfer) is 290 l/mole. Decomposition is negligible. The rearrangements correspond to those previously found upon ultraviolet irradiation, and the γ‐induced product distribution resulting from 2 in benzene and toluene is similar to that obtained photochemically with wavelengths >280 nm.
Über eine Vereinfachung der Beschreibung und Analyse von komplizierten kernmagnetischen Resonanzspektren mit Hilfe von Teilspektren
Authors: Diehl P.
Published: December 2004

After a short description of the principles of subspectral analysis, the method of subspectral transformations is introduced. Subspectral transformations transform parts of the Hamiltonian of complex nmr‐problems into the Hamiltonian of simpler subproblems. The method is applied to spectra of the type A A′ X X′, A A′ A″ A‴ X X′, A A′ A″ X X′ X″ und A B B′ X X′ which are shown to be superpositions of simple and well known subspectra.
Über ein Steroid mit wahrscheinlicher Oxazolinstruktur
Authors: Roth Max , Wagner‐Jauregg Theodor , Zirngibl Ludwig , Meier Pius , Stammbach Christian , Wagenitz Irene
Published: December 2004

Es wird die mit geringer Ausbeute verlaufende Darstellung des (wahrscheinlichen) 3β‐Acetoxy[17,16‐d]‐(2′‐methyloxazolino)‐Δ5‐androstens (IV) durch Isomerisierung von 3β‐Acetoxy‐17‐acetylamino‐16‐methyl‐Δ5,16‐androstadien (IIA) mittels Bortrifluoridätherat in Eisessig beschrieben. IIA entsteht, neben einem isomeren Amid IIB, bei der BECKMANN'schen Umlagerung von 3β‐Acetoxy‐16‐methyl‐Δ5,16‐pregnadien‐20‐on‐oxim, das in 3 verschieden schmelzenden Formen erhalten wurde.
Structure chimique des aspergillomarasmines A et B
Authors: Haenni A. L. , Robert M. , Vetter W. , Roux L. , Barbier M. , Lederer E.
Published: December 2004

La structure chimique, ainsi que la configuration de deux phytotoxines isolées d'Aspergillus flavus oryzae: les aspergillomarasmines A (XXVI) et B (VII) (cette dernière étant identique à l'acide lycomarasmique) sont établies.
Notiz über Limatin aus Aspidosperma limae WOODS
Authors: Pinar M. , Bycroft B. W. , Seibl J. , Schmid H.
Published: December 2004

From the stembark of Aspidosperma limae WOODSON the alkaloid Limatine has been isolated in small quantity and shown by spectroscopic methods to possess structure II.
Recherches sur la formation et la transformation des esters LIX. Sur la préparation de monoesters sulfuriques d'amino‐alcools et sur leur scission
Authors: Cherbuliez Emile , Čolak‐Antić Sl. , Wyss G. , Rabinowitz J.
Published: December 2004

Hydrogenosulphates of amino‐alcohols heated at 180–200° under reduced pressure yield the corresponding sulphuric monoesters.
Herstellung von Anthrachinonderivaten aus dem DIELS‐ALDER‐Addukt von 1,4‐Naphtochinon und 5,5‐Dimethoxy‐1,2,3,4‐tetrachlorcyclopentadien. 2. Mitteilung
Authors: Kniel P.
Published: December 2004

The DIELS‐ALDER adduct of 1,4‐naphthoquinone and 5,5‐dimethoxy‐1,2,3,4‐tetrachlorocyclopentadiene was transformed into the di‐O‐acetyl‐dienol (80%) which, on oxidation with chromium trioxide, gave 2,3,4‐trichloranthraquinone‐1‐carboxylic acid methylester (72%). Sodium dithionite treatment of this compound yielded 2,3‐dichloroanthraquinone‐1‐carboxylic acid (80%). Pyrolysis of the DIELS‐ALDER adduct and the diacetyldienol, followed by oxidation, led to 2,3,4‐trichloroanthraquinone‐1‐carboxylic acid methylester (9,5%) and 1,2,3,4‐tetrachloroanthraquinone (29%), respectively.
Pyridinderivate als Komplexbildner VII. Über die Koordinationstendenz von substituierten Dipicolinat‐Ionen
Authors: Anderegg G. , Bottari E.
Published: December 2004

The complex formation of 4‐aminodipicolinate ion with 14 metal cations is investigated. The results are used for a discussion of the peculiar differences in complex formation between substituted iminodiacetates and substituted dipicolinates.
Gradienten‐Elution in der Dünnschicht‐Chromatographie
Authors: Niederwieser A. , Honegger C. G.
Published: December 2004

Sheet‐chromatography (thin‐layer‐ or paper‐chromatography) with gradientelution is easily performed by filling a capillary tubing solvent reservoir with effluent of a mixing battery (fig. 1a, b) and connecting the reservoir with a small solvent‐distributor laying on the sheet (fig. 1c). Hydrostatic pressure as well as suction by capillary forces regulate the solvent flow into the sheet in such a way, that all liquid leaving the reservoir is immediately picked up by the adsorbens. A simple relation therefore exists between the distance travelled by the solvent front and the volume flown out of the reservoir (fig. 10). If the composition of the mixing battery effluent is given, the solvent composition at the «immersion line» is known any time during chromatography. A micro mixing battery with up to 7 closed chambers (fig. 3) has been proved useful to produce quickly concentration gradients of liquids differing in density. The gradient‐elution is demonstrated to be reproducible on a thinlayer plate of 200 × 200 mm along the starting line (fig. 12) as well as on different thin‐layer plates (fig. 13). The method has been applied to mixtures of dyestuffs and mixtures of lipids and is able to separate e.g. squalen, O‐stearyl cholesterol, tri‐, di‐, monoglycerides, cholesterol, and polar lipids as phospholipids (fig. 14). The separation power of a gradient‐elution is highest in radial chromatography (fig. 11).
Reaktivität von Koordinationsverbindungen XIII. Zum Mechanismus der Eisen(II)‐katalysierten Autoxydation eines Formazanfarbstoffes
Authors: Trefzer K. , Fallab S.
Published: December 2004

The kinetics and the mechanism of the Fe2+ catalysed autoxidation of a chelate forming formazyl derivative have been studied. Inhibition by CN− suggests formation of a ternary complex with O2 as a reactive intermediate in which oxidation takes place via electron transfer without formation of an iron(III)‐compound. The Fe2+ keeps the reactants in a favourable position and provides suitable orbitals for the electron transfer from the ligand to the O2‐molecule.
Eine neue Fulvensynthese
Authors: Schaltegger H. , Neuenschwander M. , Meuche Doris
Published: December 2004

Fulvene (I) better than 98% pure has been prepared in 74% yield by reacting at 0° equimolar quantities of triethylamine and the mixture of the acetoxymethylcyclopentadienes IIa + IIb.
Isolierung und Struktur von Pleiocarpolin, Pleiocarpolinin und Kopsinolin. 8. Mitteilung über Pleiocarpa‐Alkaloide
Authors: Kump Christl , Seibl J. , Schmid H.
Published: December 2004

Aus Pleiocarpa pycnantha K. SCHUM. STAPF, var. tubicina STAPF PICHON, und Pleiocarpa mutica BENTH. wurden die drei neuen Indolalkaloide Pleiocarpolin (I), Pleiocarpolinin (II) und Kopsinolin (III) isoliert und charakterisiert. Auf Grund ihrer Eigenschaften und ihrer thermischen Umwandlung unter Abspaltung von Formaldehyd in die drei bekannten Pleiocarpa‐Alkaloide IV, V, VI liessen sich für die neuen Alkaloide die Formeln I–III ableiten. Das C,N‐Skelett dieser Alkaloide enthält 21 Kohlenstoffatome.
Flotation und Koordinationschemie. Über eine Methode zur Anreicherung von Ga3+
Authors: Seiler H. , Erlenmeyer H.
Published: December 2004

Ga has been enriched by a factor 3 in Al‐ores by flotation using 2‐methyl‐8‐hydroxy‐quinoline as collector. The Ga was assayed by colorimetry and by activation analysis.
Polarographie an Festelektroden II. Gleichspannungspolarographie von Blei an einer Silberelektrode vom Kammertyp
Authors: Schmidt E. , Gygax H. R.
Published: December 2004

Die Abscheidung von Blei auf Silberelektroden aus wässeriger Lösung wird mittels Gleichspannungspolarographie unter Verwendung einer Messelektrode vom Kammertyp untersucht Die Ausbildung der ungesättigten (submonomolekularen) Bedeckung erfolgt bei hinreichend geringer Potentialvorschubrate polarographisch reversibel, wobei sich die Bleiaktivität als Bedeckungsisotherme vom LANGMUIR'schen Typ darstellen lässt. Die Strombilanz des Elektrodenvorgangs wird durch coulometrische Auswertung der Polarogramme geprüft.
Beiträge zur Chemie der pflanzlichen Plastiden 4. Mitteilung. Über die Fettsäuren in grünen und gelben Blättern von Acer platanoides (L.)
Authors: Eichenberger W. , Grob E. C.
Published: December 2004

Es wurden die Gesamtfettsäuren von grünen und gelben Blättern von Acer platanoides (L.) untersucht. Linolensäure erwies sich sowohl in den ganzen Blättern als auch in den Chloroplasten als Hauptfettsäure, gefolgt von Palmitinsäure und Linolsäure. Bei der Herbstvergilbung beobachtet man einen besonders starken Abfall des Linolensäuregehaltes, während der Gesamtanteil der gesättigten Säuren praktisch unverändert bleibt. Auffallend ist die bei der Herbstvergilbung feststellbare relative und absolute Zunahme der kürzerkettigen (C12 und C14) Fettsäuren. Über deren Entstehung können z.Z. keine Angaben gemacht werden. Da eine Neubildung der Linolensäure während der Herbstverfärbung unwahrscheinlich ist, müssen wir annehmen, dass die im Lutein‐3‐ester enthaltene Linolensäure den Chloroplasten entstammt.
Atropisomerie in der Dibenzo[a, d]cyclohepten‐Reihe. Untersuchungen über synthetische Arzneimittel, 14. Mitteilung
Authors: Ebnöther A. , Jucker E. , Stoll A.
Published: December 2004

Es wurden 3‐Chlor‐5‐(1‐methyl‐4‐piperidyliden)‐5H‐dibenzo[a, d]cyclohepten (III), 5‐(3‐Dimethylaminopropyliden)‐5H‐dibenzo[a, d]cyclohepten (IV) und 3‐Chlor‐5‐(1‐methyl‐4‐piperidyliden)‐10,11‐dihydro‐5H‐dibenzo[a, d]cyclohepten (VIII) in optische Antipoden gespalten und deren Racemisierungsgeschwindigkeiten bestimmt. Durch Einführung von grossen Substituenten in die Stellung 5 des 5H‐Dibenzo[a, d]‐cycloheptens wird der Übergang von einer Konformation in die andere so stark erschwert, dass bei Zimmertemperatur Konformationsisomere gefasst werden können.
Peroxidbildung bei der Autoxydation N2‐substituierter Methylhydrazine
Authors: Aebi H. , Dewald Beatrice , Suter Hedi
Published: December 2004

1. Formation of peroxide as produced in autoxidation of N2‐substituted methylhydrazine derivatives has been studied with the WARBURG technique. The following methods for its detection have been used: (a) chemical and enzymatic estimation of H2O2, (b) coupled formate oxidation (H14COONa → 14CO2), (c) methemoglobin formation in suspensions of acatalatic red cells as a «biological indicator».
Recherches sur la formation et la transformation des esters LXI. Sur la réaction entre phosphite d'éthyle et les esters trifluoroacétylacétiques monochloré et monobromé, ainsi que les trifluoroacétones monochlorée et monobromée
Authors: Cherbuliez Emile , Weber G. , Rabinowitz J.
Published: December 2004

1,1,1‐Trifluoro‐3‐bromo‐acetone has been prepared by a new and simple procedure: bromination of ethyl trifluoroacetoacetate yielding the α‐monobromo derivative, and cetogenic splitting of this keto ester in 50% hydrobromic acid.
Über die adrenale Steroid‐Biosynthese in vitro I. Umwandlung endogener und exogener Vorstufen im Nebennieren‐Homogenat des Rindes
Authors: Kahnt F. W. , Neher R.
Published: December 2004

The conditions of the adrenal steroid biosynthesis in vitro have been thouroughly studied, using beef adrenal cortex homogenate with endogenous and exogenous precursors. The preformed endogenous precursor has been identified with cholesterol. Its aerobic incubation produced a 10–30‐fold increase of the amount of originally present corticosteroids, such as cortisol, corticosterone, aldosterone, 18‐hydroxy‐corticosterone and 19‐hydroxy‐corticosterone. From a wide variety of exogenous precursors studied so far, corticosterone proved quantitatively to be the best precursor for aldosterone, whereas the pathway involves probably 18‐hydroxy‐corti‐costerone. The results suggest that the optimal conditions for the formation of aldosterone are different from those for other corticosteroids. The methods used are fully described.
Die ESR.‐Spektren der Radikal‐Anionen 1, 6‐überbrückter Cyclodecapentaene
Authors: Gerson F. , Heilbronner E. , Böll W. A. , Vogel E.
Published: December 2004

The ESR.‐spectra of the radical anions of 1, 6‐methano‐cyclodecapentaene (II) and of 1, 6‐oxido‐cyclodecapentaene (VII), as well as of some of their deutero‐derivatives, are reported. The observed spin populations are in essential agreement with the predictions derived from a simple HMO‐model, if the electron repelling effect of the bridging groups is included. The reduced width of the spectra may be due to direct leakage of the unpaired electron into the CH‐σ‐orbitals, as a consequence of the breakdown of σ‐π‐orthogonality in the non‐planar π‐electron systems.
ESR.‐Spektren der Radikal‐Anionen des 1,8‐Dinitro‐ und des 1,4,5,8‐Tetranitronaphtalins
Authors: Gerson F. , Adams R. N.
Published: December 2004

ESR spectra of the radical anions of 1, 8‐dinitro‐ and 1,4,5,8‐tetranitronaphthalene (I resp. II) have been recorded. There is no evidence of association between the radical anion of II and alkali metal cations in ethereal solvents. The nitrogen coupling constant in this radical anion has been found to be markedly dependent on temperature. A simple MO‐model of weakly interacting π‐electron systems accounts qualitatively for the large differences in the spin populations of the nitrosubstituents in the radical anions of I and II.
Komplexe XXXVII. Die EDTA‐Komplexe des Vanadiums(V)
Authors: Przyborowski L. , Schwarzenbach G. , Zimmermann Th.
Published: December 2004

By adding EDTA to a solution of metavanadate, the complex VO2Y3− or its protonated forms VO2HY2− and VO2H2Y− are produced. A number of cristallized salts containing these anions have been prepared and characterized. The stability constants of the complexes have been obtained photometrically. In the reaction of the complex with alkali, VO2Y3− is in equilibrium with H2VO4− and HVO42−, and its study furnishes also the equilibrium: 2 H2O + VO2+ ⇌ H2VO4− + 2 H+. The effective stability of the 1:1‐Vanadium(V)‐EDTA complex over the entire pH‐range is given.
Ein Isoteniskop zur Messung der Totaldampfdrucke einphasiger flüssiger Systeme
Authors: Arm H. , Daeniker H. , Schaller R.
Published: December 2004

Es wird die Konstruktion und Handhabung eines Isoteniskops beschrieben, das die Total‐Dampfdrucke einphasiger flüssiger Systeme mit einer Genauigkeit von mindestens ± 0,05 Torr zu messen erlaubt.
Die Reaktion von O‐Methylcaprolactimäther mit Carboinsäurechloriden
Authors: Stoll B. , Griehl W.
Published: December 2004

Die Reaktion von O‐Methylcaprolactimäther mit Carbonsäurechloriden ergibt entgegen der bisher vertretenen Ansicht in meist sehr guter Ausbeute die entsprechenden N‐Acylcaprolactame und nicht die O‐Acylverbindungen. Mit Hilfe dieser Reaktion wurden eine Reihe dieser N‐Acyllactame hergestellt. Ihre Konstitution wurde durch IR.‐Absorptionsspektrogramme sowie durch Mischschmelzpunkte mit authentischen Derivaten bewiesen.
Die Oxydation von wässerigem Propionaldehyd durch Brom
Authors: Konecny Jan
Published: December 2004

The rate of oxidation of aqueous propionaldehyde by bromine has been measured potentiometrically at two temperatures. The reaction is first order in propionaldehyde and free bromine respectively and is catalysed by acetate ions. Tribromide ions are inactive.
Über die Reaktionskinetik von Wüstit mit Kohlenmonoxid und mit Wasserstoff
Authors: Kohl Herbert Karl , Marincek Borut
Published: December 2004

Die Reduktionsgeschwindigkeit von Wüstit mit Wasserstoff, Kohlenmonoxid und mit Wasserstoff‐Kohlenmonoxid‐Gemischen wurde gravimetrisch gemessen. Mittels der zur Untersuchung gelangenden Oxidproben konnte unter den gewählten Reduktionsbedingungen (900 bis 1200°, 726 ± 10 Torr) die Umsetzungsgeschwindigkeit an der Phasengrenze Oxid/Gas bestimmt werden. Für die Geschwindigkeitskonstante bei Reduktion mit Wasserstoff bzw. Kohlenmonoxid wurde dieselbe Temperaturabhängigkeit gefunden. Die Reduktionsgeschwindigkeit mit Gasgemischen ergibt sich als Summe aus den Teilreduktionsgeschwindigkeiten der beiden Komponenten. Die bei Reduktion mit Wasserstoff gefundene Temperaturabhängigkeit stimmt mit älteren Ergebnissen gut überein.
Studien über Triazine als eventuelle orale Antidiabetika
Authors: Suter Hans , Zutter Hans
Published: December 2004

Zwei neue Biguanide und 10 neue Triazine wurden hergestellt um festzustellen, ob die Stabilisierung der Biguanidgruppe durch Ringbildung die antidiabetische Wirksamkeit und Verträglichkeit steigert.
Metallionen und H2O2. V. Über Struktur und Aktivität der den H2O2‐Zerfall katalysierenden Cu2+‐Komplexe III. Versuche zur Lösung von Strukturproblemen mit Hilfe der Katalyseeigenschaften
Authors: Erlenmeyer H. , Müller U. , Sigel H.
Published: December 2004

The catalytic properties of Cu2+‐chelates of the following ligands in H2O2 decomposition have been investigated: N, N′‐diglycyldiaminoethane (I), N, N′‐diglycyl‐1,5‐diaminopentane (II), N, N′‐diglycyl‐1,3‐diaminopropane (III) [6], glycinamide (IV), glycylglycinamide (V) and polymyxin B (VI). It is confirmed that the catalysis of H2O2 decomposition by Cu2+‐chelates and the formation of ternary peroxo complexes (absorbing at 360 nm) depend on the number of free coordination positions. It is now shown that in reversal the number of free coordination positions on the Cu2+ in its complexes can be determined by measuring their catalytic activity on the H2O2 decomposition, and their absorption at 360 nm.
Synthese von 4‐Chlorpiperidinen
Authors: Fankhauser R. , Grob C. A. , Krasnobajew V.
Published: December 2004

The preparation of 4‐chloropiperidine (1a) and its N‐alkyl derivatives 1b–le from 4‐piperidones 2 and from 4‐pyridone (6), respectively, is described.
Synthèse de la désamino1‐Orn8‐vasopressine, de la désamino1‐Phe2‐Orn8‐vasopressine, de la désamino1‐Ile3‐Orn8‐vasopressine (= désamino1‐Orn8‐oxytocine) et de la désamino1‐Phe2‐Ile3‐Orn8‐vasopressine (= désamino1 ‐Phe2‐Orn8‐oxytocine)
Authors: Huguenin R. L.
Published: December 2004

Four analogues of the vasopressins have been synthesised: Deamino1‐Orn8‐vasopressin, Deamino1‐Phe2‐Orn8‐vasopressin, Deamino1‐Ile3‐Orn8‐vasopressin (= Deamino1‐Orn8‐oxytocin) and Deamino1‐Phe2‐Ile3‐Orn8‐vasopressin (= Deamino1‐Phe2‐Orn8‐oxytocin). The two former have been prepared by condensation of tripeptide azides with an hexapeptide. The two latter have been obtained from the hexapeptide by the recurring method, using active trichlorophenyl esters.
Über die adrenale Steroid‐Biosynthese in vitro. III. Selektive Hemmung der Nebennierenrinden‐Funktion
Authors: Kahnt F. W. , Neher R.
Published: December 2004

The possibility is discussed of inhibiting the adrenocortical functions either selectively or preferentially by blocking the hydroxylations in positions 11β, 17α, 18 and 19 of the steroid nucleus or in 20α, 21 and 22 of the side chain, which are necessary for the formation of the individual corticosteroids from cholesterol. Many compounds with or without other biological activities, such as o,p′‐DDD, Amphenone B, various blockers of cholesterol biosynthesis, heparinoids and various heterocyclic compounds, are shown to be devoid of a specific blocking activity on the adrenal cortex in vitro. However, amongst a large group of glutaric imides a few compounds proved to be active, mainly by blocking the 20α‐hydroxylation of cholesterol, the most active being a cyclic hydrazide; the secretion in vivo of corticosteroids greatly decreased in response to 3–20 mg/kg. A new class of compounds active in vitro was found among simple imidazole derivatives, which block 17α, 18 and 19‐hydroxylation.
Zur kenntnis des Fuerstions; Synthesen alkylsubstituierter Phtalsäuren
Authors: Scarpa J. S. , Ribi M. , Eugster C. H.
Published: December 2004

Der diterpenoide Blattfarbstoff Fuerstion aus Fuerstia africana T. C. E. Fries lieferte bei der energischen Oxydation mittels HNO3 Mellophansäure und substituierte Phtalsäuren, von denen zwei als 4‐Methyl‐3‐(2′‐carboxyäthyl)‐phtalsäure 2A bzw. 4‐Methyl‐3‐(3′‐carboxypropyl)‐phtalsäure 3A strukturell aufgeklärt wurden. Es werden die Synthesen von 2A, von 3‐Methyl‐6‐(2′‐carboxyäthyl)‐phtalsäure 6, von 3‐Methyl‐4‐(2′‐carboxyäthyl)‐phtalsäure 17 und von verwandten Verbindungen beschrieben. Furylacrylsäuren lassen sich mit Hydrazin (Diimid‐Verfahren) zu Furylpropionsäuren reduzieren.
Über die Reduktion von 2‐Cyanomethyl‐benzimidazol
Authors: Balsiger R. W. , Hänni H. , Schindler O.
Published: December 2004

Die Hydrierung von 2‐Cyanomethyl‐benzimidazol (I) mit Raney‐Nickel in Alkohol in Gegenwart von Piperidin führt nicht zum erwarteten 2‐(β‐Piperidino‐äthyl)‐benzimidazol (III), sondern zu 2‐(β‐Piperidino‐vinyl)‐benzimidazol (II).
Die Ableitung der Stereochemie von 1‐Isopropyl‐4‐methyl‐bicyclo[3.1.0]hexan (cis‐und trans‐Thujan) durch Protonenresonanz‐Spektroskopie
Authors: Dieffenbacher A. , von Philipsborn W.
Published: December 2004

100 Mc/s proton NMR. spectra of the two diastereoisomeric thujanes obtained by reduction natural thujone have been measured and are given a detailed analysis. The relative configurations of the two hydrocarbons are deduced. Together with the known R‐configuration at C(1) the absolute configurations can be derived, (−)‐cis‐thujane having the (1R:4S:5R)‐ and (+)‐trans‐thujane the (1R:4R:5R)‐configuration. It can be shown that the trans‐isomer adopts a boat‐like conformation of the bicyclohexane ring system whereas cis‐thujane prefers a half‐chair conformation with a flattened cyclopentane ring.
Cinobufaginol Über Krötengifte, 32. Mitteilung
Authors: Linde Horst , Hofer Peter , Meyer Kuno
Published: December 2004

Aufklärung der Konstitution von Cinobufaginol (= Substanz G aus Ch'an Su) mit Hilfe der Protonenresonanzspektroskopie.
DNA‐Abbau und Oxydation von o‐Phenylendiamin. Metallionen und H2O2, 8. Mitteilung
Authors: Zell R. , Sigel H. , Erlenmeyer H.
Published: December 2004

In earlier papers it has been stated, that the catalytic activity of several metal complexes in H2O2 decomposition is caused by the formation of ternary HOO−‐Me2+‐ligand complexes. The present investigation deals with the effect of traces of metal ions on two other reactions. The degradation of DNA by autoxidizable, H2O2 producing methylhydrazines is stopped by P2O74−. This effect is shown to be due to complex formation of the metal ions with P2O7−4, preventing the formation of the catalytically active ternary complex. The catalysis of the H2O2 oxidation of o‐phenylenediamine by pyridine‐2,6‐dicarboxylic acid is dependent on traces of Fe2+ ions; this latter effect is equally suppressed by P2O7−4.
6, 6‐Dialkyl‐ und 6, 6‐Polymethylen‐fulvene
Authors: Meuche Doris
Published: December 2004

The electronic, infrared and NMR spectra of 6, 6‐dialkyl‐fulvenes and of 6, 6‐poly‐methylene‐fulvenes are reported.
Zur Synthese des Ecdysons. IV. Mitteilung über Insektenhormone. Die Synthese des natürlichen Häutungshormons
Authors: Kerb U. , Schulz G. , Hocks P. , Wiechert R. , Furlenmeier A. , Fürst A. , Langemann A. , Waldvogel G.
Published: December 2004

Ecdysone (9), a hormone responsible for the skin shedding process of arthropoda, has been synthesized. (20S)‐2β,3β‐Diacetoxy‐20‐formyl‐5β‐pregn‐7‐en‐6‐one was prepared from the corresponding carboxylic acid and converted into ecdysone by a GRIGNARD reaction with 2‐methyl‐3‐butyn‐2‐ol tetrahydropyran‐2‐yl ether, followed by hydrogenation of the triple bond, removal of the protecting groups, and hydroxylation in the 14α‐position. C‐22‐isoecdysone was obtained as a by‐product.
Unterscheidung der Penicilloinsäuren von funktionellen Derivaten ihrer. α‐Carboxylgruppe mittels Penamaldat‐Stabilitätsbestimmung
Authors: Schneider C. H. , De Weck A. L.
Published: December 2004

The distinction between derivatives of penicilloic acids with modified α‐carboxyl function and the corresponding penicilloic acids themselves by means of a photometric test is described. The procedure involves conversion of the penicillin derivatives to penamaldates by the action of mercuric chloride, and comparison of the stability of the extinction at 282 nm in phosphate buffer at pH 7,4. The stabilities of the free penamaldates made from penicilloic acids are quite low (half life 4 to 5 minutes) and contrast with the high stabilities of penamaldoyl derivatives obtained from the α‐derivatives of penicilloic acids. Some characteristics of the method are discussed, and its potential usefulness for the quantitative analysis of mixtures of penicilloic acid and α‐derivatives of penicilloic acid is demonstrated.
Chemische Aspekte der Penicillin‐Allergie: Die direkte Penicilloylierung von ϵ‐Aminogruppen durch Penicilline bei pH 7, 4
Authors: Schneider C. H. , De Weck A. L.
Published: December 2004

The aminolysis of penicillins by ε‐amino groups at pH 7,4 is demonstrated. It is shown that penicillenic acid, formed spontaneously under these conditions from penicillins, does not contribute significantly to the penicilloylations observed. Penicillin therefore can directly form penicilloylamides under physiological conditions.
Herstellung von Aryl‐isothiocyanaten aus Arylaminen und Bis‐diäthylthiocarbamoylsulfiden
Authors: Marquardt F.‐H.
Published: December 2004

The preparation of aryl‐isothiocyanates from aryl‐amines and bis‐diethylthiocarbamoyl sulfides is reported and mechanisms are proposed for these reactions of thiocarbamoyl derivatives.
Organische Phosphorverbindungen XXVI. Phosphor‐31 chemische Verschiebungen in primären Phosphinen
Authors: Maier Ludwig
Published: December 2004

An empirical equation is given which allows the calculation of the 31P‐chemical shifts of primary phosphines.
Note sur la préparation et la scission de l'acide (diméthyl‐3, 3‐butyl)‐phosphorique
Authors: Cherbuliez Emile , Espejo O. , Jaccard S. , Rabinowitz J.
Published: December 2004

3,3‐Dimethylbutanol treated with polyphosphoric acid or with an equimolecular amount of POCl3 gives rise to 3,3‐dimethylbutyl phosphoric acid, isolated as baryum salt (yield 20 to 30%) or as sodium salt (yield 15%). Stable in NaOH 1N at 100°C, this monoester is split at pH 4.5 and in HCl 1N much slower than choline phosphate.
Die Beeinflussung des photochemischen Verhaltens von Farbstoffmolekeln in Lösung durch Fremdsubstanzen. Lösungen von Chinizarin in aliphatischen Kohlenwasserstoffen in Gegenwart aromatischer Verbindungen
Authors: Somers B. G. , Zürcher R. F. , Labhart H.
Published: December 2004

The acceleration of the photolysis of several anthraquinone derivatives by admixture of various substances, notably of carbonyl compounds ans lead(IV) salts has been studied in a variety of solvents. The sensitization of the photolysis results from the production of radicals either directly from the irradiated lead salts or from the solvent upon hydrogen atom abstraction by the excited carbonyl compounds, probably in the triplet state. The reaction of these radicals with the dye results in the formation of several derivatives of its leuco form, whose absorption in the visible and ultraviolet closely resemble that of the unsubstituted leuco form. These reactions are observed in very dilute solutions, in which intermolecular energy transfer is not expected to occur.
De la chimie des ptérines. 16e communication. Obtention de ptérines méthylées et de leurs dérivés tétrahydrogénés
Authors: Viscontini M. , Bobst A.
Published: December 2004

Nous décrivons la synthèse des ptérines méthylées, dont les dérivés tétrahydrogénés nous ont servi à établir le mécanisme probable de réoxydation des tétrahydroptérines en dihydro‐7,8‐ptérines, en passant par l'intermédiaire d'une dihydroptérine quinoïdique instable.
Synthese und pharmakologische Wirkung einiger 5‐Alkyl‐ und 5‐Alkenyl‐4‐hydroxyisophtalsäuren und ‐Ester
Authors: Mühle H. , Bänninger H. , Ernst L. , Meier W.
Published: December 2004

The synthesis of some 5‐alkyl‐ and 5‐alkenyl‐4‐hydroxy (resp. acyloxy‐ resp. alkoxy)‐isophthalic acids and esters is described. Some of the described derivatives exhibit analgetic, antipyretic and antiphlogistic activity.
Adigosid, Strukturbestimmung Glykoside und Aglykone, 282. Mitteilung
Authors: Hoffmann St. , Weiss Ek. , Reichstein T.
Published: December 2004

This publication reports the preparative isolation of adigoside from the seeds of Nerium oleander L. with a yield of 250 mg crystalline adigoside per kilogram of seeds. Mild acid hydrolysis of adigoside gave crystalline D‐diginose (8) and amorphous adigenin (6), which in turn gave a crystalline mono‐O‐acetyl derivative 7. With the aid of physical methods, degradative reactions and partial synthesis of 7, the structure of adigenin was proved to be that of 16‐O‐isovaleryl‐gitoxigenin. On the basis of molecular rotation it was shown that the sugar in adigoside (2), in accordance with the KLYNE Rule, is bound in the β‐D‐pyranosidic form. Adigoside showed no (or at the most very weak) digitalis type activity on the cat. This lack of activity must be due to the esterification of the 16‐hydroxyl group by isovaleric acid, as it is known that an acetyl residue in the same position enhances rather than lowers the activity of 16β‐hydroxy‐cardenolides.
Synthesen substituierter Butenolide
Authors: Haefliger W. , Petrzilka T.
Published: December 2004

Es wird die Darstellung von Butenoliden des Typs II beschrieben, und es werden die Erfahrungen diskutiert, die bei der Kondensation dieser Verbindungen mit β‐Mercapto‐acrylestern gemacht wurden.
Photolyse von 2, 2, 4, 4‐Tetramethylcyclobutanon‐Derivaten
Authors: Hostettler H. U.
Published: December 2004

The photochemical reactions of the 2, 2, 4, 4‐tetramethylcyclobutanones 1–6 carrying various substituents in 3‐position were investigated. The major reaction in alcoholic solution or in the presence of other protic compounds was the formation of the semicyclic acetals 7–12. Parallel to this reaction decarbonylation occurred, leading to stable cyclopropane derivatives in some cases, depending on the substituents present. Cyclopropanes with an exocyclic double bond underwent ring opening easily or, in case of an exocyclic carbon‐nitrogen double bond, added alcohol, thus forming cyclopropane O, N‐ketals. Alkyl‐acyl biradicals are proposed as common intermediates for both photoreactions. Based on analogy to similar photoreactions reported in the literature, the formation of the semicyclic acetals is assumed to involve a carbene intermediate.
Steroide und Sexualhormone. 231. Mitteilung. Die Synthese von N‐Acetyl‐3‐aza‐A‐homo‐5β, 10α‐androstan und seines 5α‐Isomeren (Vorläufige Mitteilung)
Authors: Eggart Frl. G. , Wehrli H.
Published: December 2004

A synthesis of N‐acetyl‐3‐aza‐A‐homo‐5β, 10α‐androstane (14) and N‐acetyl‐3‐aza‐A‐homo‐5α, 10α‐androstane (15) is described, starting from 2‐oxo‐17β‐acetoxy‐Δ5‐10α‐androstane (4).
Der Einfluss von Dimethylsulfoxid und Dioxan auf die Reaktionen von 2,4‐Dinitrofluorbenzol und 2,4‐Dinitrochlorbenzol mit Piperidin in Benzol. 4. Mitteilung über nucleophile aromatische Substitutionsreaktionen
Authors: Bernasconi C. F. , Kaufmann M. , Zollinger Hch.
Published: December 2004

(1) The rates of the reactions of 2,4‐dinitrofluoro‐ and 2,4‐dinitrochlorobenzene with piperidine as influenced by the addition of dimethylsulfoxide and p‐dioxane have been measured in benzene solution.
Stoffwechsel‐Endprodukte von PhyllochinonMenachinon‐4, Ubichinon‐9 und Hexahydroplastochinon‐4 (Phytylplastochinon)
Authors: Gloor U. , Würsch J. , Mayer H. , Isler O. , Wiss O.
Published: December 2004

Phylloquinone, menaquinone‐4, ubiquinone‐9 and hexahydroplastoquinone‐4,i.e.compounds with isoprenoid side‐chains which differ by their length and degrees of unsaturation, are degraded in the rat in the same way as tocopherols. After oxidative shortening of the side‐chain to seven C‐atoms, the metabolites are excreted in the urine as conjugates, presumably glucuronides, which, after hydrolysis, can be isolated as γ‐lactones.
Etude de composés d'addition des acides de Lewis XXVIII. Constantes de Hammett et vibration carbonyle des composés formés par TiCl4 et SbCl5 avec des chlorures de benzoyle parasubstitués
Authors: Jaccard J.‐Cl. , Susz B. P.
Published: December 2004

The adducts of benzoyl chlorides p‐substituted by CH3O, CH3, and H with the electronic acceptors SbCl5 and TiCl4 have been prepared, and the IR. absorption spectra of the solid products studied.
Zur Kenntnis des Muscazons. 24. Mitteilung über Inhaltsstoffe von Fliegenpilzen
Authors: Reiner R. , Eugster C. H.
Published: December 2004

Für die aus Amanita muscaria (L. ex FR.) HOOKER isolierte racemische α‐Aminocarbonsäure Muscazon wird die Struktur eines [2(3H)‐Oxazolonyl‐(5)]‐glycins chemisch abgeleitet.
Über die Eigenschaften des Xp‐Teils von AnBXp‐Kernresonanzspektren
Authors: Diehl P. , Weisenhorn P.
Published: December 2004

The subspectral breakdown of the X‐part in AnBXp‐spectra is derived and the general properties of the subspectra are discussed. The nature of the asymmetry of Xp‐spectra for n > 1 is explained and conditions for its disappearance are given. The degeneration of the Xp‐part into deceptively simple spectra is described and degeneration conditions are derived. The determination of relative signs of coupling constants is discussed.
Die sterischen Bedingungen der Fragmentierungsreaktion. II. Teil. Stereoisomere 3‐Aminocyclohexyl‐p‐toluolsulfonate. Fragmentierungsreaktionen, 15. Mitteilung
Authors: Burckhardt U. , Grob C. A. , Kiefer H. R.
Published: December 2004

The solvolytic fragmentation of cis‐ and of trans‐3‐amino‐cyclohexyl p‐toluenesulfonates 8a and 9a and the corresponding N, N‐dimethyl derivatives 8b and 9b has been studied. In 80% ethanol the cis‐amino‐tosylates 8a and 8b react faster than the homomorphous cis‐3‐alkyl‐cyclohexyl tosylates 11a and 11b to yield fragmentation product exclusively or predominantly. The synchronous mechanism predictable on stereoelectronic grounds is therefore indicated.
Photochemische Reaktionen. 39. Mitteilung. Photochemische Umwandlungen von endo‐Tricyclo[4.3.12,5.0]‐decadien‐(3,8)‐dion‐(7,10) und cis‐8, 9‐Dihydroindenon
Authors: Baggiolini E. , Herzog E. G. , Iwasaki S. , Schorta R. , Schaffner K.
Published: December 2004

In boiling xylene the cyclopentadienedione 1 is thermally decarbonylated to cis‐8,9‐dihydroindenone (8). This method avoids secondary reactions and allows the preparation of 8 in high yield.
Recherches dans la série des cyclitols XXXIV. Sur le complexe diborique du scyllitol
Authors: Posternak Th. , Lucken E. A. C. , Szente A.
Published: December 2004

Le complexe diborique du scyllitol, préparé autrefois par réduction du scyllo‐ms‐inosose au moyen du borohydrure de sodium, s'obtient plus simplement par action à température ordinaire du tétraborate de sodium sur le scyllitol. Sa structure de complexe bis‐tridenté a été confirmée par RMN. Ses constantes de formation ont été déterminées. Un mode pratique d'obtention du scyllitol est décrit.
Die Pregnanderivate der Wurzeln von Asclepias lilicina WEIMARCK. II. Strukturbestimmungen Glyoside und Aglykone, 291. Mitteilung
Authors: Sawlewicz Ludwika , Weiss Ek. , Reichstein T.
Published: December 2004

Partial formulae have been derived for the nine lilacinosides which were isolated, partly in pure form, and for two related substances which were only obtained as a mixture. These substances are derived basically from two pregnane derivatives (sarcostin and deacetyl‐metaplexigenin) present in partially benzoylated form. Of these were isolated genin B = 12,20‐di‐O‐benzoyl‐sarcostin (1), genin C = 12‐O‐benzoyl‐20‐O‐acetylsarcostin (2), and genin D, which could be identified with 12‐mono‐O‐benzoyl‐desacetyl‐metaplexigenin (4). These three genins are bound to different sugars, the latter being present as mono‐, di‐, tri‐ and probably tetra‐saccharides. The structures of these were partially derived: after mild hydrolysis three new disaccharides were obtained, which are named asclepobiose (U1), lilacinobiose (U2) and digalilobiose (U5). U1 and U2 were isolated in crystalline form. On hydrolysis U1 yielded 3‐O‐methyl‐6‐deoxy‐D‐allose (U3), U2 yielded 3‐O‐methyl‐6‐deoxyglucose (thevetose), and digitalose was obtained from U5.
Optische Rotationsdispersion und Konfiguration bei Cardenoliden
Authors: Burkhardt F. , Meier W. , Fürst A. , Reichstein T.
Published: December 2004

In accordance with the results of Weiss & ZIFFER, the ORD spectra of cardenolides with few exceptions show a distinct Cotton effect, caused by the butenolide ring. The two extrema lie at about 260 and 228 nm; the extremum at shorter wave length is very difficult to measure, and that at longer wavelength shows fine structure in dioxane. 14α,17β‐cardenolides having either a hydrogen atom or a hydroxyl group at C‐14 and no double bond in rings C and D show a negative Cotton effect, whereas compounds of the other three stereoisomeric types (14α,17α; 14β,17α and 14β,17β) show a positive Cotton effect. In the case of cardenolides having an oxo group, the extremum of the oxo group at shorter wavelength overlaps that of the butenolide ring at longer wavelength. In spite of this the latter extremum could still be seen distinctly in all cases investigated to date.
Recherches sur les arǒmes 13e communication [1] Sur 1′ arǒme de café. I
Authors: Stoll M. , Winter M. , Gautschi F. , Flament I. , Willhalm B.
Published: December 2004

The analysis of a coffee concentrate is described: 202 constituents have been identified, 154 of which for the first time. Some of these compounds are new chemicals; their synthesis is described. Most identifications are based upon mass spectrometry combined in many cases with IR. spectrometry and comparison with reference compounds. MS. and IR. data are given in detail. The analysis shows that a large number of minor constituents is present, many of which could not be identified.