bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die ESR.‐Spektren der Radikal‐Ionen des 1,3,6,8‐Tetraazapyrens
Authors: Gerson F. 
Published: December 2004

Abstract1,3,6,tetraazapyrene (I) forms a radical anion by alkali metal reduction in 1,Z‐dimethoxyethane as well as a radical cation in conc. sulphuric acid. The ESR hyperfine structures of the radical ions are very similar, and this similarity is discussed in terms of simple MO‐theory.
Zum Mechanismus der Metallionen‐Katalysierten Hydrolyse von Adenosintriphosphat (ATP). I
Authors: Schneider P. W. , Brintzinger H. 
Published: December 2004

AbstractThe rate of hydrolysis of ATP metal ion complexes – as well as the sign of optical rotation of the resulting ADP complexes – are shown to result from special steric arrangements of metal ion, adenine ring and phosphate groups in the respective nucleotide complexes. It is concluded that catalytic – and possibly also enzymatic – enhancement of reactivity of ATP depends on the selective coordination of either a metal ion or a proton to the β‐PO2−group. Such selective coordination – versus the concurrent coordination to the more basic terminal –P032−group – is brought about by the occurrence of an additional ligand in juxtaposition to the β‐PO2− group, providing a kind of chelate effect in favour of the complex isomer in which the terminal POP bond is labilized.
Optische Messung der Kinetik von simultaner Diffusion und chemischer Reaktion 1. Ordnung in planparallelen Platten
Authors: van Tets A. , Günthard Hs. H. 
Published: December 2004

AbstractThe kinetics of a process is considered which consists of simultaneous diffusion and first order decay reaction of a substance within thin slabs. Several formulas, tables and graphs are given which may be useful for the determination of the relevant constants oi the model, i. e. surface and bulk diffusion coefficients 𝒟 and D, and rate constant k respectively. For this model it is shown that the saturation value of optical density may rather easily be estimated from a plot of optical density vs logarithm of time t (see table 1).
Über chelatbildende Salicylsäure‐Analoge der Thiophenreihe
Authors: Courtin A. , Class E. , Erlenmeyer H. 
Published: December 2004

AbstractDerivatives of 2‐carboxy‐3‐hydroxy‐thiopheneand of 3‐carboxy‐4‐hydroxy‐thio‐ phene have been synthesized in order to examine the influence of different bond orders on the chelating properties of the salicylic acid grouping in these compounds, which show a blue color reaction with aqueous FeCl3.
Die Glykoside der Wurzeln von Asclepias glaucophylla SCHLECHTER. Glykoside und Aglykone, 257. Mitteilung
Authors: do Nascimento J. M. , Tamm Ch. , Jäger Herb. , Reichstein T. 
Published: December 2004

AbstractThe roots of Asclepias glaucophylla SCHLECHTER are very rich in steroids;two distinct groups are present: cardenolides and ester glycosides of pregnane derivatives.
Über die Sorption von Gasen an Feststoffen. 1. Mitteilung: Konstruktion einer Thermo/Vakuum‐ und einer Thermo/Druck‐Waage
Authors: Böhlen B. , Guyer A. 
Published: December 2004

AbstractEs werden zwei Thermowaagen beschrieben, die es ermöglichen, in einem weiten Temperaturbereich Wägungen bei Drucken von 0–760 Torr bzw. 1–20 ata durch zu‐führen. Ihre Arbeitsweise wird diskutiert und anhand von Eichmessungen werden Genauigkeit und Leistungsfähigkeit der beiden Geräte überprüft.
Über die Sorption von Gasen an Feststoffen. 2. Mitteilung: Praktische Anwendungsbeispiele einer Thermo/Vakuum‐und einer Thermo/Druck‐Waage
Authors: Böhlen B. , Hausmann W. , Guyer A. 
Published: December 2004

AbstractAnhand einiger praktischer Beispiele werden verschiedene Anwendungsmöglichkeiten einer neuen Thermo/Vakuum‐ und einer Thermo/Druck‐Waage aufgezeigt.
Synthèse de La Phe2‐Orn8‐vasopressine et de la Phe2‐oxytocine, deux analogues de la vasopressine doués d'une activité Pressorique sélective
Authors: Huguenin R. L. 
Published: December 2004

AbstractPhe2‐Orn8‐vasopressin and Phe2‐Orn8‐oxytocin have been prepared by synthesis Both analogues, but especially the second one, have a more selective pressor activity than the natural vasopressins and than most hitherto synthesized analogues these hormones.
Substances naturelles isolées de microorganismes. 1re communication, Préliminaire. Nouvelles ptéridines et nouvelles porphyrines obtenues à partir de Pseudomonas roseus fluorescens J. C. MARCHAL 1937
Authors: Viscontini M. , Pouteau‐Thouvenot M. , Bühler‐Moor R. , Schroeder M. 
Published: December 2004

AbstractA partir d'un bouillon de culture synthétique de Pseudomonas roseus fluorescens J. C. MARCHAL 1937, nous avons isolé et caractérisé l'hydroxyméthyl‐8‐ptérine, la L‐thréo‐trihydroxypropyl‐8‐ptérine que nous appelons monaptérine, et une zinco‐porphyrine que now appelons usticaphyrine.
Welkstoffe und Antibiotika. 30. Mitteilung. Ausgangsprodukte zur Totalsynthese des Javanicins
Authors: Hardegger E. , Steiner K. , Widmer E. , Corrodi H. , Schmidt Th. , Knoepfel H. P. , Rieder W. , Meyer H. J. , Kugler F. , Gempeler H. 
Published: December 2004

AbstractZur Herstellung von Ausgangsprodukten zur Synthese des Javanicins wurden, ausgehend von Vanillin (1) über Methoxyhydrochinon (2), dessen Ester 2a, b und 1, 2, 4‐Trimethoxybenzol (2c) mit FRIES'scher Verschiebung, FRIEDEL‐CRAFTS‐Reaktion und MANNICH‐Kondensation eine grössere Anzahl Verbindungen vom Typus 3, 4, 5, 6 hergestellt, welche die neu eingeführten Substituenten in o‐, m‐, p‐Stellung zu den bereits vorhandenen Sauerstoff‐Funktionen tragen. Weitere Auf‐baureaktionen unter Anwendung von Malonestersynthesen führten zu monocyclischen Präparaten von Typus 20, 21, die z. T. bereits sämtliche C‐ und O‐Atome des Javanicins in der richtigen Anordnung aufwiesen, bisher aber nicht zu Javanicin‐Derivaten cyclisiert werden konnten.
Welkstoffe und Antibiotika. 33. Mitteilung. Selektive Spaltung der Äther chelierter Phenole und Synthese von Javanicin
Authors: Hardegger E. , Widmer E. , Steiner K. , Pfiffner A. 
Published: December 2004

AbstractEs gelang unter sehr milden Reaktionsbedingungen Phenoläther, welche ein ortho‐ bzw. peri‐ständiges Carbonyl enthalten, mittels Aluminiumchlorid in Nitrobenzol in wasserlösliche Aluminiumkomplexe umzuwandeln, deren Zersetzung mit Wasser oder Säure zu den freien Phenolen führte. Die Methode erlaubte u. a. die Herstellung von Javanicin und Anhydrojavanicin aus synthetischem Javanicin‐A‐dimethylather, womit die Konstitution der Naturstoffe Javanicin und Fusarubin bezüglich der Lage der Methoxylgruppe endgültig gesichert erscheint.
Recherches expérimentales sur l'ozonation des fumarate, maléate et cinnamate d'éthyle, suivie par spectrographie d'absorption IR
Authors: Briner E. , Fliszár S. , Rossetti G. P. 
Published: December 2004

AbstractL'ozonation des fumarate, maléate et cinnamate d'éthyle a été étudiée en tenant compte des trois processus intervenant de façon plus ou moins marquée: (1) l'attaque par l'ozone de la liaison éthylénique, conduisant à la formation d'aldéhyde; (2) la scission spontanée des ozonides, aboutissant à la production d'aldéhyde et d'acide; (3) l'autoxydation des aldéhydes formirs lors de l'attaque par l'ozone.
Isomere des Chanoclavins aus Claviceps purpurea (Fr.) Tul. (Secale cornutum) 63. Mitteilung über Mutterkornalkaloide
Authors: Stauffacher D. , Tscherter H. 
Published: December 2004

AbstractFrom a rye ergot alkaloid fraction rich in chanoclavine we isolated three new crystalline alkaloids, each a stereoisomer of the known chanoclavine. Their configurations could be elucidated by NMR.‐spectra. According to the nomenclature of the dihydro‐d‐lysergic acid series the isolated alkaloids are named: chanoclavine‐(I) (formerly named chanoclavine), chanoclavine‐(II), rac. chanoclavine‐(II) and isochanoclavine‐(I).
Eine experimentelle Methode zur Ermittlung der Singulett‐Triplett‐Konversionswahrscheinlichkeit und der Triplett‐Spektren von gelösten organischen Molekeln Messungen an 1,2‐Benzanthracen
Authors: Labhart Heinrich 
Published: December 2004

AbstractSmall changes in optical density due to chopped cross illumination are measured as a function of wavelength. The theory of this effect shows that from such measurements it is possible to find not only the spectrum of molecules in the lowest triplet state, but also the quantum yield of triplet generation. Measurements were made with outgassed solutions of 1,2‐benzanthracene in hexane at room temperature. The triplet‐triplet spectrum has been determined in the range from 270 to 510 mμ (see fig. 5) and the quantum yield for triplet generation was found to be νT = 0.55 ± 0.10.
Die Farbreaktion der Phenole mit dem Chlor/o‐Tolidin‐Reagens
Authors: Weber S. H. , Langemann A. 
Published: December 2004

AbstractPhenols produce colours with chlorine/o‐tolidine, a method usually applied for the detection of NH‐groups. A series of phenols has been tested and the results are compared with standard tests for phenols. The procedure described is particularly suitable for spray reagents in paper and thin layer chromatography.
Intrasphärische und extrasphärische Komplexe mit Phosphatliganden. Infrarotspektren von Phosphatkomplexen in wässeriger Lösung
Authors: Brintzinger H. 
Published: December 2004

AbstractThe structures of complexes with ligands containing the PO32− group – monomethyl phosphate, diphosphate, monomethyl diphosphate and adenosine‐5′‐triphosphate – have been studied by infrared absorption measurements in aqueous solution.
Die Glykoside der Samen von Vallaris solanacea (ROTH) O. K. Isolierungen. Glykoside und Aglykone, 263. Mitteilung
Authors: Kaufmann Heinz , Wehrli W. , Reichstein T. 
Published: December 2004

AbstractThe seeds of Vallaris solanacea (ROTH) O.K. are very rich in cardiac glycosides. Eight KEDDE‐positive substances have been detected through paper‐ and thinlayerchromatography. All of them could be isolated in crystalline form. The yields varied between 0,03% and 0,9% with respect to the dry weight of the seeds.
Zur Kenntnis der BOHN‐SCHMIDT'schen Reaktion. 1. Mitteilung. Isolierung und Strukturaufklärung neuartiger Verbindungen aus der Oleumschmelze von α‐Hydroxyanthrachinonen
Authors: Winkler J. , Jenny W. 
Published: December 2004

AbstractIn the course of an investigation of the BOHN‐SCHMIDT reaction, cyclic bis‐sulfonic esters of tetrahydroxy‐anthracenes have been isolated from solutions of 1‐hydroxy‐, 1,4‐dihydroxy‐, 1,5‐dihydroxy‐, and 1,4,5,8‐tetrahydroxy‐anthraquinones in high‐percent oleum. The constitution of the new compounds is confirmed by UV., IR., NMR. and mass spectra.
Organische Phosphorverbindungen XVII. Darstellung von Alkylen‐bis‐phosphonsäurechloriden und Alkylen‐bis‐thiophosphonsäurechloriden und deren Reaktion mit GRIGNARD‐Verbindungen
Authors: Maier Ludwig 
Published: December 2004

AbstractThe synthesis and some physical properties of alkylene bis‐(phosphonic dichlorides), Cl2P(O)(CH2)n(O)PCl2, and of alkylene bis‐(phosphonothioic dichlorides), Cl2P(S)(CH2)n(S)PCl2, a new class of compounds, are reported. The reactions of alkylene bis‐(phosphonothioic dichlorides) with GRIGNARD reagents and of CH3P(S)Br2 with di‐GRIGNARD reagents are also described. Some physical properties of several diphosphine disulfides and of two cyclic tertiary phosphine sulfides have been determined.
Eine ergiebige Synthese von Rosenoxid
Authors: Ohloff G. , Lienhard B. 
Published: December 2004

AbstractEs wird ein ergiebiger Weg zur Darstellung eines Gemisches der Rosenoxide 6 und 7 beschrieben. Die aus dem Epoxid 8 des β‐Citronellols – über die Öffnung des Oxiranringes durch sekundäre Amine – erhaltenen N‐Oxide liefern durch Pyrolyse das 2,6‐Dimethyl‐3‐octendiol‐(2,8) (4), das mit Säuren in die diastereomeren Tetrahydropyran‐Derivate 6 und 7 übergeführt wird.
Über chelatbildende Salicylsäure‐Analoge der Thiophenreihe. II. Komplexchemische Untersuchungen
Authors: Courtin A. , Sigel H. 
Published: December 2004

AbstractAcidity constants of 2‐carbethoxy‐3‐hydroxy‐5‐R‐thiophenes (R  H, CH3, phenyl, p‐biphenylyl, α‐naphtyl) and of 3‐carbethoxy‐4‐hydroxy‐2‐R‐thiophenes (R  H, CH3, phenyl) and stability constants of their complexes with some divalent metal ions have been determined. The stability of the chelates is discussed as a function of the respective bond orders of the α–β and β–β′ bonds of the thiophene ring.
Beiträge zur Chemie der Carotinoide 2. Mitteilung. Säurekatalytische Reaktionen von Isozeaxanthin
Authors: Grob E. C. , Pflugshaupt R. P. 
Published: December 2004

AbstractEs wurde die säurekatalysierte Reaktion von Isozeaxanthin in Benzol‐0,01 M HCl untersucht. Für die einzelnen Reaktionsprodukte werden auf Grund chromatographischer, spektroskopischer und chemischer Eigenschaften Konstitutionsformeln vorgeschlagen.
Reaktivität von Koordinationsverbindungen XIV. Reversible O2‐Bindung an Eisen(II)‐Phtalocyanintetrasulfonsäure
Authors: Vonderschmitt D. , Bernauer Klaus , Fallab S. 
Published: December 2004

AbstractOxidation and reduction properties of iron(II) and iron(III) phthalocyaninetetrasulphonic‐acids are described. The reversible reaction of the iron(II) compound with molecular oxygen leads to a binuclear complex FeII · O2 · FeII. At a neutral pH no oxidation to the iron(III) state occurs. The stability of the O2‐complex has been determined.
Note sur la préparation de quelques isothiocyanates
Authors: Cherbuliez Emile , Weber G. , Wyss G. , Rabinowitz J. 
Published: December 2004

AbstractBy reacting m‐trifluoromethyl‐aniline, m‐trifluoromethyl‐benzyl‐amine and p‐fluorophenyl‐ethyl‐amine respectively with CSCl2, the authors have obtained the corresponding isothiocyanate of m‐trifluoromethyl‐phenyl, m‐trifluoromethyl‐benzyl and p‐fluorophenyl‐ethyl.
Recherches sur la formation et la transformation des esters LX. Sur la réaction des isothiocyanates avec des amino‐alcools soit libres soit estérifiés avec des acides du phosphore
Authors: Cherbuliez Emile , Baehler Br. , Jindra H. , Weber G. , Wyss G. , Rabinowitz J. 
Published: December 2004

AbstractAminoalkyl phosphoric monoesters with a primary or secondary amino group react with isothiocyanates in the presence of an alkali (2 moles of NaOH for 1 mole of the monoester and 1 mole of the isothiocyanate) to yield almost quantitatively the corresponding sodium N‐(aryl(aralkyl)‐thiocarbamyl)‐aminoalkyl phosphates; these thioureas are relatively soluble in water and generally also in methanol or ethanol.
Protonenresonanzspektren von Oximen aromatischer Aldehyde
Authors: Pejković‐Tadić I. , Hranisavljević‐Jakovljević M. , Nešić S. , Pascual C. , Simon W. 
Published: December 2004

AbstractThe NMR.‐spectra of 9 pairs of isomeric benzaldoximes are discussed. Syn‐anti structural assignment is possible using chemical shift data.
Photoreaktionen von Acridin und Acridinabkömmlingen Sowie von Arylketonen mit Methanol
Authors: Göth H. , Cerutti P. , Schmid H. 
Published: December 2004

AbstractBeim Bestrahlen von Acridin in Methanol bzw. Äthanol entstanden neben dem 9,9′‐Biacridan (1) durch Methanol‐ bzw. Äthanol‐Addition unter C‐Hydroxyalkylierung die Verbindungen 2 und 3. Auch 9‐Methylacridin liess sich in entsprechender Weise zur Verbindung 5 umsetzen. Dieselbe Reaktion gehen 10‐Methyl‐ und 9,10‐Dimethyl‐acridiniumchlorid ein, wobei die Alkohole 6 und 7 resultieren. Beim Bestrahlen des 10‐Methylacridiniumchlorids in Äthanol entsteht auch das Dimere 9.
Sur la réaction de l'acide β‐mercaptopropionique, du β‐diéthylamino‐éthylmercaptan et de la cystéine avec divers isothiocyanates
Authors: Cherbuliez Emile , Buchs A. , Marszalek J. , Rabinowitz J. 
Published: December 2004

AbstractBy treating β‐mercaptopropionic acid with aryl (aralkyl) isothiocyanates in weak alkaline medium, the authors have obtained the corresponding β‐(N‐aryl(aralkyl)‐thiocarbamoylthio)‐propionic acids which, heated 2 hours at 120°, yield the corresponding 3‐aryl(aralkyl)‐4‐oxo‐2‐thiono‐tetrahydrothiazines.
Sur l'absorption des semicarbazones des cétones terpéniques dans l'ultra‐violet
Authors: Naves Yves‐René , Retamar Juan Alberto , Ricciardi Armando Italo 
Published: December 2004

AbstractThe UV. absorptions of semicarbazones of mono‐ and bicyclic terpene ketons are tabulated. It is possible to correlate structural features with characteristic displacements (shifts) or intensity changes of the absorption, in particular for the semicarbazones of unsaturated ketones and α‐epoxy‐ketones.
Entropiebedingte Komplexbildung Thermodynamische Daten der Komplexbildung mit dem Tripolyphosphat‐Ion
Authors: Anderegg G. 
Published: December 2004

AbstractThe formation of the 1:1‐complex of 10 bivalent metal ions with tripolyphosphate has been studied. The stability constants and the heats evolved by formation of the 1:1‐complexes have been determined. In all cases the complex formation is endotherm and entropically favored.
Sennosid C, ein neues Glucosid aus Cassia angustifolia (Senna). 9. Mitteilung über Anthraglykoside
Authors: Schmid W. , Angliker E. 
Published: December 2004

AbstractFrom the leaves of Cassia angustifolia VAHL a new glycoside, sennoside C, has been isolated in crystalline form and shown by chemical means to be the 8,8′‐di‐glucoside of rhein‐aloe‐emodin‐dianthrone. This confirms the tentative formula of sennoside C by LEMLI, who deduced it by paper chromatography of the breakdown products of the aglycone. Sennoside C has the same stereochemical configuration as sennoside A.
Identifizierung der als «6β, 15α‐Dihydroxyprogesteron», «11α, 15β‐Dihydroxyprogesteron» und «12α, 15β‐Dihydroxyprogesteron» beschriebenen Steroide mit 12α, 15β‐Dihydroxyprogesteron
Authors: Dodson R. M. , Langbein G. , Muir R. D. , Schubert A. , Siebert R. , Tamm Ch. , Weiss‐Berg E. 
Published: December 2004

AbstractThe microbial transformation products described as «6β, 15α‐dihydroxy‐progesterone», «11α, 15β‐dihydroxy‐progesterone» and «12β‐dihydroxy‐progesterone» are shown to be identical and to possess the structure of 12β, 15α‐dihydroxy‐progesterone (1).
Exposition à la lumière de plaques cristallines de bromure d'argent, au cours de leur développement électrolytique
Authors: Steiger R. , Boissonnas Ch. G. 
Published: December 2004

AbstractThin polycristalline sheets of pure or doped silver bromide have been developed indirectly at the contact of a platinum wire connecting the crystal with a photographic developer. During the development, the crystals have been exposed several times to an intense flash of white or monochromatic light.
Calorimètre pour la mesure des chaleurs de mélange des liquides
Authors: Garcia J. G. Fernández , Boissonnas C. G. 
Published: December 2004

AbstractA calorimeter has been designed for measuring the heat of mixing of liquid systems, which eliminates the need to correct for changes in the composition of the vapour phase on mixing. Improved accuracy has been obtained. It permits the measurements of thermic effects of the order of 0.005 joule, corresponding to temperature differences of 10−4 of a degree. Heats of mixing have been measured for the system hexadecane‐hexane, the results of which are highly satisfactory.
Synthesen in der Carotinoid‐Reihe 21. Mitteilung. Synthese von 2,2′‐Diketo‐spirilloxanthin (P 518) und 2,2′‐Diketo‐bacterioruberin
Authors: Schwieter U. , Rüegg R. , Isler O. 
Published: December 2004

Abstract2,2′‐Diketospirilloxanthin and 2,2′‐diketobacterioruberin have been prepared via the corresponding 15,15′‐dehydro compounds by condensation of 15,15′‐dehydroapo‐4,4′‐carotenedial (C30) with 3‐methoxy‐(resp. 3‐hydroxy)‐3‐methyl‐2‐butanone. 2,2′‐Diketospirilloxanthin was identical with natural P 518.
Über Struktur und Aktivität der den H2O2‐ Zerfall katalysierenden Cu2+‐Komplexe IV. Katalatisches und peroxydatisches Verhalten von Cu2+‐Komplexen mit Adenin‐Nucleotiden und DNA. Metallionen und H2O2, 7. Mitteilung
Authors: Sigel H. , Erlenmeyer H. 
Published: December 2004

AbstractThe catalytic activity of Cu2+ complexes in the decomposition of H2O2, and the formation of ternary peroxo compounds – measured by their absorption at 360 nm– of the following ligands have been investigated: AMP (I), ADP (II), ATP (III), AMP‐N(1)‐oxide (IV), DNAAMP = Adenosin‐5′‐monophosphat; ADP = Adenosin‐5′‐diphosphat; ATP = Adenosin‐5′‐triphosphat; AMP‐N(l)‐oxid = Adenosin‐5′‐monophosphat‐N(1)‐oxid; DNA‐Desoxyribonucleinsäure.
, PO43− and P2O74−.
Welkstoffe und Antibiotika. 35. Mitteilung. Konstitution des Diaporthins und Synthese der Diaporthinsäure
Authors: Hardegger E. , Rieder W. , Walser A. , Kugler F. 
Published: December 2004

AbstractDas aus Kulturen von Endothia parasitica (MURR.) AND. isolierte, optisch aktive Welketoxin Diaporthin C13H14O5 gab mit Alkali Acetaldehyd und optisch inaktive Diaporthinsäure. deren Bruttoformel auf C11H12O5 berichtigt wurde. Die Interpretation der NMR.‐Spektren führte zu den Strukturformeln von Diaporthin (I) und Diaporthinsäure (III), welche durch Synthese der letzteren bewiesen wurden.
Biosynthese der Digitoxose in Digitalis lanata EHRH. (Vorversuch). Desoxyzucker, 39. Mitteilung
Authors: v. Euw J. , Reichstein T. 
Published: December 2004

AbstractStrongly radioactive digitoxin (6) could be isolated (without dilution) in crystalline form from young plants of Digitalis lanata after their inoculation with D‐Glucose‐[6‐14C] using the wick method. Hydrolytic cleavage of this digitoxin gave digitoxigenin (11) and D‐digitoxose (7), both being isolated in crystalline form (without dilution). The genin was found to be 4 times more active, pro mole, than the digitoxose. This can be best explained when one assumes that the plant converts 1 mole of D‐glucose into 3 moles of acetic acid. After degradation of the digitoxose using NaJO4, acetaldehyde (as the crystalline p‐nitrophenylhydrazone) and formic acid (as the Pb salt) could be isolated. The acetaldehyde carried 65% and the formic acid 8,45% of the activity of the digitoxose. This is compatible with the assumption that digitoxose is formed in the plant from D‐glucose without re‐arrangement of the carbon chain. The appreciable activity of the formic acid could be derived from the relatively large proportion of radioactivity lost (ca. 38,9%), partly in the form of C1‐subunits, in the transformation of the intermediary lanosterol into digitoxigenin. This lost activity may be incorporated in unspecifically labelled D‐glucose which then re‐enters the biosynthetic pathway.
Die Struktur der Drevogenine. 2. Mitteilung Struktur von Drevogenin P. Glykoside und Aglykone, 278. Mitteilung
Authors: Sauer H. H. , Weiss Ek. , Reichstein T. 
Published: December 2004

AbstractDrevogenin A was converted in several steps (acetylation, hydrogenation, dehydration, hydrogenation, the haloform reaction and energetic alkaline hydrolysis) into 3β, 11α, 12β‐trihydroxy‐5α‐etianic acid, which could be characterised by its crystalline methyl ester (15) and its tri‐O‐acetyl methyl ester (16). The same acid was obtained by partial synthesis starting from hecogenin. Taking into consideration earlier results [1], the structure of drevogenin P is proved to be 3β, 11α, 12β, 14β‐tetrahydroxy‐20‐oxo‐Δ5‐pregnene (7). Energetic hydrolysis of dihydro‐3‐O‐acetyldrevogenin A gave a mixture of 17αH‐ and 17βH‐desacyl‐kondurangogenin A, which were obtained in crystalline form after separation by chromatography. The only difference between the basic structures of the drevogenins and kondurangogenin A is the presence of a double bond in the 5‐position in the former.
Stoffwechselprodukte von Mikroorganismen. Granaticin B
Authors: Barcza S. , Brufani M. , Keller‐Schierlein W. , Zähner H. 
Published: December 2004

AbstractFrom a strain of Streptomyces violaceoruber, ETH 11382, a new antibiotic, granaticin B. has been isolated. Granaticin B is an L‐rhodinoside of the previously described antibiotic granaticin.