bluuebunny/crossref_metadata_2025 huggingface dataset:
Photochemische Umwandlungen. XXXIV [1]. Photochemische Isomerisierung substituierter Benzonorbornadiene
Authors: Eberbach W. , Würsch P. , Prinzbach H.
Published: December 2004

The benzonorbornadiene derivatives 4, 5, 6 and 19 give upon direct photoexcitation the benzo‐tricyclo [3.2.0.02, 7] heptenes 14, 17, 21 and 23 in yields up to 60%. Sensitization by acetone improves the yields considerably. The spectral data of the substrates 4, 5, 6, 7 and 19, of the photoproducts 14, 17, 21 and 23, as well as of the dihydrobenzonorbornadienes 13, 16 and 22, are presented.
Synthese und Kristallstruktur von Tetramethylammonium‐Gismondin
Authors: Baerlocher Ch. , Meier W. M.
Published: December 2004

A new synthetic zeolite, (CH3)4NA1Si3O8, H2O, has been synthesized and shown to be an isotype of the mineral gismondine, CaAl2Si2O8,4H2O. Sodium and other cations can be introduced by ion exchange after thermal decomposition of the organic cation. A continuous structural change to «cubic» NaP has thereby been recorded, which indicates that the latter is also based on a gismondine‐type aluminosilicate framework.

The crystal structure of tetramethylammonium‐gismondine has been determined using X‐ray powder data supplemented by electron diffraction. The crystals are tetragonal, a = 9.84 and c = 10.02 Å, with 4 formula units per unit cell. The apparent symmetry of the framework structure is I41/amd, however, this is violated by the organic cation. Two of the methyl groups are pointing to oxygen atoms of the framework and the short methyl‐oxygen distances indicate CH ⃛ O interaction.
Synthèses dans la série des bis‐indéno‐fluorènes, VI [1] Dihydro‐12, 15–6H‐bis‐indéno[1. 2‐b; 2′.1′‐h]fluorène et dihydro‐14, 15–8H‐bis‐indéno[2. 1‐a; 2′. 1′‐h]fluoréne
Authors: Stauner Thomas , Avar Lajos , Chardonnens Louis
Published: December 2004

Starting from cyclohexene and 2, 2′, 5, 5′‐tetramethylbiphenyl the linear bisindenofluorene 12, 15‐dihydro‐6H‐diindeno [1.2‐b; 2′.1′‐h] fluorene (XX) has been synthesized in 5 steps (overall yield 27%). As an intermediate product the 6, 12, 15‐trioxo‐derivative XIX (greyish green crystals, blue alcaline vat) was obtained. By a side way, the 6‐oxo‐derivative of XX and the already known monoangular bis‐indenofluorene 14, 15‐dihydro‐8H‐diindeno [2.1‐a; 2′.1′ ‐h] fluorene (XXVII) were also obtained. XX can also be prepared in several steps starting from 3‐methyl‐fluorene or fluorene.
Peptide and Amide Bond Formation in Aqueous Solutions of Cyclic or Linear Polyphosphates as a possible prebiotic process
Authors: Rabinowitz Joseph
Published: December 2004

En faisant réagir des acides aminés en solution aqueuse, à température ordinaire et à pH env. 11, en présence de polyphosphates cycliques ou linéaires, on obtient des dipeptides avec des rendements allant jusqu'a 40%. Dans le cas de la sérine, on note uniquement la formation du dérivé O‐phosphorylé, soit l'acide sérinephosphorique.

En faisant réagir un mélange de glycine (ou d'alanine) et de l'une des trois amines suivantes: phosphosérine, phosphoéthanolamine ou acide amino‐2‐éthanephosphonique, en solution aqueuse en présence de trimétaphosphate, on obtient à côté de la diglycine des quantités appréciables d'amide mixte, soit la N‐glycyl‐phosphosérine, la N‐glycyl‐phosphoéthanolamine et l'acide N‐glycyl‐amino‐2‐éthanephosphonique respectivement. Nous pensons que des peptides, phosphopeptides et amides mixtes de ce type sont également formés lors de réactions par décharge électrique dans des systèmes contenant de la phosphine, du méthane, de l'ammoniac et de l'eau.

Un mécanisme probable conduisant à la liaison peptidique ou amide serait la formation intermédiare d'un acylphosphate cyclique ou ouvert de l'acide aminé, qui réagirait ensuite avec le groupe amino d'une deuxième molécule d'acide aminé (→ peptide) ou de l'amine (→ amide).

Ces réactions présenteraient un certain intérêt dans la formation prébiotique de la liaison peptidique et amide, ainsi que de la liaison ester phosphorique.
3‐O‐Phosphoryl‐digitoxigenin. Partialsynthetische Versuche in der Reihe der Herzgifte, 3. Mitteilung
Authors: Sawlewicz Ludwika , Linde Horst H. A. , Meyer Kuno
Published: December 2004

Die Bereitung von 3‐O‐Phosphoryl‐digitoxigenin (III), seines Dinatrium‐ und Piperaziniumsalzes sowie seines Dimethylesters IV wird beschrieben.
Further Examples of Steric Inhibition to Cyclopropyl Conjugation in α,β‐unsaturated esters
Authors: Jorgenson Margaret J. , Gonzenbach Hans‐Ulrich
Published: December 2004

Das UV.‐Absorptionsmaximum des α, 7β‐ungesättigten Esterchromophors wird in Cyclopropylacrylsäureestern durch den Dreiring bathochrom um ca. 24 nm verschoben [2]. Durch die Substitution mit Methylgruppen in den γ‐(2a, b), α‐ und γ‐(3a, b) sowie β‐ und γ‐Stellungen (1a, b) wird gezeigt, dass dieser auxochrome Effekt stark von der Konformation abhängt und sogar negativ werden kann, wenn die für die Konjugation optimale bisektriche Lage von Dreiring und Doppelbindungsebene sterisch destabilisiert wird.
C‐glycosides III. Cyclo‐additions dipolaires ‐ 1,3 d'oxydes de nitriles et de nitrilimines. Communication préliminaire
Authors: Tronchet J. M. J. , Jotterand A. , Le Hong N. , Perret Melle F. , Thorndahl‐Jaccard Mme S. , Tronchet Mme J. , Chalet J. M. , Faivre Melles L. , Hausser C. , Sébastian C.
Published: December 2004

1.3‐dipolar cycloaddition of alkenes (or alkynes) on sugars‐nitriloxides and nitrilimines led respectively to 3‐glycosyl‐isoxazolines (or isoxazoles) and 3‐glycosyl‐pyrazolines (or pyrazoles). 5‐glycosyl‐isoxazolines were similarly prepared from arylnitriloxides and α‐ or ω‐unsaturated sugars. These new C‐glycosides are potential antiviral and anti‐tumor agents.
Oxymercuration. Substituted 9‐oxabicyclo[4.2.1]‐ and 9‐ oxabicyclo[3.3.1]nonanes
Authors: Ganter C. , Wicker K. , Zwahlen W. , Schaffner‐Sabba K.
Published: December 2004

Oxymercuration of cis, cis‐1, 5‐cyclooctadiene (1), followed by treatment with potassium iodide and subsequent reaction with iodine, leads to six isomeric diiodides which represent the three possible stereoisomers 2, 3, and 4 of 2, 5‐diiodo‐9‐oxabicyclo[4.2.1]nonane as well as 5, 6, and 7 of 2, 6‐diiodo‐9‐oxabicyclo[3.3.1]nonane. The isolation, structure determination and some reactions of these diiodo compounds 2–7 are described.
The Conjugative Interaction between π‐Orbitals and Walsh‐e‐Orbitals in Bullvalene and Related Systems
Authors: Bischof P. , Gleiter R. , Heilbronner E. , Hornung V. , Schröder G.
Published: December 2004

The photoelectron spectra of bullvalene (1), dihydrobullvalene (2), tetrahydrobullvalene (3), hexahydrobullvalene (4), and homotropylidene (5) have been recorded. The first bands in these spectra are correlated with orbitals which are linear combinations of the Walsh‐e‐orbitals and of the olefinic π‐orbitals. This assignment is based on a qualitative ZDO‐molecular orbital model as well as on the results of extended Hückel calculations. As anticipated, a large interaction is found between the π‐ and the Walsh‐e‐orbitals in 1, 2, and 3, indicative of a resonance integral β ≈ −2 eV, i.e. of the same order as that between the two double bond π‐orbitals in butadiene (β = − 2.4 eV). In 5 the interaction between π‐ and Walsh‐e‐orbitals is negligible.
Étude comparative de la décarboxylation des acides (benzothiazolyl‐2)‐acétique, ‐3‐propionique, ‐glyoxylique et ‐pyruvique
Authors: Baudet Pierre , Otten Claude
Published: December 2004

Benzothiazol‐2‐yl glyoxylic acid and α‐amino‐benzothiazol‐2‐yl acetic acid hydrochloride undergo decarboxylation at room temperature. This facile decarboxylation seems to depend on the following requirements: (a) the formation of a planar zwitterion; (b) a distance of about 2.2 Å between the charges of the zwitterion; (c) the stabilisation of the intermediate carbanion.

In fact the following compounds which do not fulfil these three conditions do not decarboxylate at room temperature: α‐hydroximino benzothiazol‐2‐yl acetic acid, α‐amino benzothiazol‐2‐yl acetic acid as internal salt, benzothiazol‐2‐yl acetic acid, 3‐(benzothiazol‐2‐yl)‐propionic acid and benzothiazol‐2‐yl pyruvic acid.
Synthese von 2,7‐Dioxa‐isotwistan und 2,7‐Dioxatwistan. Vorläufige Mitteilung
Authors: Ganter C. , Wicker K.
Published: December 2004

The syntheses of 2,7‐dioxa‐isotwistane (14), 2,7‐dioxa‐twistane (19), and some of their derivatives (6–13 and 15–18) are described.

The twistane‐skeleton was obtained by a molecular rearrangement starting from the iodo‐iso‐twistane compound 8.
Über die Umlagerung von Benzo[b]‐1, 4‐thiazepinen und 1, 4‐Thiazepinen
Authors: Wilhelm Max , Schmidt Paul
Published: December 2004

The rearrangement of differently substituted 1, 4‐thiazepines under various reaction conditions has been investigated. 2‐Phenyl‐4‐methylthio‐benzo [b]‐1, 4‐thiazepine (3) and 2‐phenyl‐benzo [b]‐1, 4‐thiazepine‐4 (5H)‐thione (2) extrude sulfur under the catalytic influence of bases and rearrange into 2‐methylthio‐4‐phenyl‐quinoline (4) and 4‐phenyl‐thiocarbostyril (6) respectively. Under the same conditions, 2‐phenyl‐4‐methylthio‐2, 3‐dihydro‐benzo [b]‐1, 4‐thiazepine (11) rearranges to 2‐styryl‐benzothiazine (12), whereas the dioxide 18shows no tendency to rearrange. 2,7‐Diphenyl‐hexahydro‐1,4‐thiazepine‐5‐one(19) could be converted into 2‐styryl‐5‐phenyl‐2‐thiazoline (20) by treatment with polyphosphoric acid. The possible mechanisms of these rearrangements are discussed.
Die Bildung von L‐3‐Acylamino‐6,7‐dihydroxy‐hydrocumarinen aus N‐Acyl‐3‐(3,4‐dihydroxyphenyl)‐L‐alaninen
Authors: Kaiser A. , Koch W. , Scheer M. , Wölcke U.
Published: December 2004

Aus den N‐Acyl‐3‐(3,4‐dihydroxyphenyl)‐L‐alaninen 1a, 1b und 1c entstehen bei der Oxydation unter anderm die L‐3‐Acylamino‐6,7‐dihydroxy‐hydrocumarine 2a, 2b und 2c. Diese Reaktion stellt einen präparativ brauchbaren Weg zur Synthese von 3‐(2,4,5‐Tri‐hydroxyphenyl)‐L‐alanin (6‐Hydroxy‐L‐DOPA, 3) aus 3‐(3,4‐Dihydroxyphenyl)‐L‐alanin dar.
Valenzisomerisierung von cis‐Dienonen, II. 5‐Phenylpenta‐2, 4‐dienaldehyde [1]
Authors: Schiess P. , Seeger R. , Suter Chr.
Published: December 2004

The 5‐Phenylpenta‐2,4‐dienaldehydes 4, and 7, show an uncatalized cis‐trans‐isomerization of the 4,5‐double bond above 70 °C. The negative value of the activation entropy for these reactions points to the formation of the bicyclic valence isomeric 2H‐Pyrans 5 and 8 respectively in the rate determining step. Intermediate 5 can be trapped as its tetracyanoethylene cycloadduct 11.

The cis‐trans isomeric 1,6‐diphenyl‐hexa‐1,3,5‐trienes 12a and 12b undergo above 150° a disrotatory ring closure to the bicyclic dienes 13 and 14 respectively.
N(a)‐Demethylseredamin, ein neues Alkaloid aus Rauwolfia sumatrana; absolute Konfiguration von Seredamin. 140. Mitteilung über Alkaloide
Authors: Hanaoka M. , Hesse M. , Schmid H.
Published: December 2004

From Rauwolfia sumatrana Jack (Apocynaceae) the two new indole alkaloids serpentinine and N(a)‐demethylseredamine were isolated. By chemical and spectroscopic evidence and by correlation experiments the latter was shown to have structure 2. the exact position of the aromatic methoxyl group was established by an investigation of the brominated derivative 12. The aromatic ORD. Cotton effect of N(a)‐acetyl‐N(a)‐demethyl‐seredamine (5) and its O‐acetyl derivative 4 as well as the ketone Cotton effect of purpeline (9) suggest that all the alkaloids of the seredamine group have the same absolute stereochemistry as ajmaline (1). This was confirmed by a direct chemical correlation of seredamine (7) with ajmaline.
Crystal and Molecular Structures of Benzylideneaniline, Benzylideneaniline‐p‐carboxylic acid and p‐methylbenzylidene‐p‐nitroaniline
Authors: Bürgi H. B. , Dunitz J. D.
Published: December 2004

The structures of the title compounds have been established by X‐ray crystal structure analysis, based on three‐dimensional diffractometer data. Bond lengths and angles are given, and the thermal motion of the molecules in the crystals is discussed. The most striking feature of all three molecules is the twist of the aniline ring out of the CNCC plane by 41–55°.
Zur Biogenese des Antibioticums Phomin. 1. Teil: Die Grundbausteine
Authors: Binder M. , Kiechel J.‐R. , Tamm Ch.
Published: December 2004

A number of potential 14C‐ and 3H‐labelled precursors were fed to growing cultures of Phoma spec. (Strain S 298), after the rate of formation of phomine (cytochalasin B; C29H37NO5) had been determined. By chemical degradation of [14C]‐phomine and [3H, 14C]‐phomine the distribution of the radioactivity originating from the incorporated precursors was determined. The results demonstrate that the building blocks of phomine are 1 unit of phenylalanine, 9 units of acetate or malonate respectively, and 2 units of methionine. Acetate acts as a starter and malonate as a propagator of a C16‐ or C18‐chain. A possible combination of these elements leading to phomine and to 5‐dehydrophomine is suggested.
Aminofuroxane. 1. Synthese und Struktur
Authors: Gagneux André R. , Meier René
Published: December 2004

Phenylglyoximes are transformed in a single operation into 3‐amino‐4‐phenyl‐furoxans which rearrange quantitatively to their 3‐phenyl‐4‐amino‐isomers above 80°. A mechanism for the synthesis is proposed and supported by the isolation of intermediates. Proof for the structure of both furoxan isomers and intermediate phenylaminoglyoximes rests on chemical transformations, mechanistic considerations, and the influence of certain structural changes on the UV.‐ spectra.
Allylic Oxidation of some 5,6‐Unsaturated Steroids with Lead Tetraacetate. Communication XXII on reactions with lead tetraacetate
Authors: Stefanović M. , Jokić A. , Maksimović Z. , Lorenc Lj. , Mihailović M. Lj.
Published: December 2004

Oxidation of cholesteryl acetate and diosgenyl acetate with lead tetraacetate in benzene or glacial acetic acid solution results in allylic acetoxylation in the C‐7 position. These reactions are nonstereospecific, and in both solvents mixtures of the corresponding 7β‐ and 7α‐epimeric acetoxy derivatives are formed. On the basis of the results, the mechanism of this oxidation reaction is discussed.
Organische Phosphorverbindungen 41. Synthese und Eigenschaften von Polyphosphinaten und Polyphosphinsäuren [1]
Authors: Maier Ludwig
Published: December 2004

A process for the preparation of alkyl chloromethylphosphonites, ClCH2P(OR)2 (R = Et, Bu), diethyl β‐chloroethylphosphonite, ClCH2CH2P(OEt)2, and their conversion to polyphosphinates with the back‐bone structures [CH2PO2R]x and [CH2CH2P(O2R)]x, respectively, by an Arbuzov type reaction is described. Hydrolysis to the corresponding polyphosphinic acids is effected by refluxing the esters with conc. HCl for extended periods. The polyphosphinic acid with structure V is an excellent chelating agent for Ca ions.
Organische Phosphorverbindungen 42. Einige Reaktionen von Bis‐(dialkoxyphosphonyl‐methyl)‐O‐alkylphosphinaten und Tris‐(dialkoxyphosphonyl‐methyl)‐phosphinoxiden [1]
Authors: Maier Ludwig
Published: December 2004

The metallation of alkyl bis‐(dialkyloxyphosphonyl‐methyl)‐phosphinates (I) and tris‐(dialkyloxyphosphonyl‐methyl)‐phosphine oxides (II) proceeds quantitatively with Na, K, or NaH in inert organic solvents. Alkylation of these metallated derivatives is effected with alkyl halides. In addition to the mono‐alkylated products, the di‐alkylated and the non‐alkylated products are formed also.

The ester groups of II can be replaced by aryl groups by reaction with Grignard reagents to produce the corresponding tetratertiary phosphine oxides.

Reduction of II with LiAlH4 results in complete rupture of the molecule and produces only the cleavage products PH3 and CH3PH2. Chlorination of the ester groups of I and II does not lead to uniform products. Concomitant with the chlorination of the ester groups, a cleavage reaction has been observed which produces as the main product Cl2CHP(O)Cl2.

The anhydride of the hexa‐acid of II is readily obtained either by reaction of this acid with (CH3CO)2O or by reaction of II with (PhCO)2O. The titration behaviour and the high m. p. indicate an adamantane‐like structure for the anhydride.

Halogenation of the bridging PCH2P groups of I and II is achieved by reaction with aqueous alkaline hypohalite at ambient temperature. This halogenation is accompanied by partial cleavage, and analytically pure samples could not be isolated.
Stoffwechselprodukte von Mikroorganismen. 89. Mitteilung [1]. Synthese von zwei diastereomeren 2, 4, 6‐Trimethylpimelinsäuren. Ein Beitrag zur Stereochemie des Borrelidins
Authors: Keller‐Schierlein W. , Brufani M. , Muntwyler R. , Richle W.
Published: December 2004

By conventional methods a mixture of diastereomeric 2,4, 6‐trimethylpimelic acids was prepared and separated by counter‐current distribution. The two meso‐compounds were isolated in crystalline form, one of them (m.p. 130°) giving a dimethyl ester identical with a degradation product of the antibiotic borrelidin. The chirality (2‐R,4‐r,6‐S) of the acid of m.p. 130° was determined by an X‐ray structural analysis (see following paper).
Über siliciumaromatische Verbindungen. III. Trimethylsilyl‐ und Triphenylsilyl‐substituierte Farbstoffe der Anthrachinonreihe
Authors: Hopff H. , Deuber J. M. , Gallegra P. , Said A.
Published: December 2004

The influence of the presence of trimethylsilyl and triphenylsilyl groups in substituents of anthraquinone on the properties of anthraquinone vat, acid, and dispersion dyes was investigated.
Autumnariol und Autumnariniol, zwei neue Dibenzo‐α‐pyrone aus Eucomis autumnalis Graeb. Nachweis einer Fernkopplung über sechs Bindungen in den magnetischen Protonenresonanz ‐ Spektren
Authors: Sidwell W. T. L. , Fritz H. , Tamm Ch.
Published: December 2004

From bulbs of Eucomis autumnalis Graeb (Liliaceae) autumnariol (1) and autumnariniol (4), two new substituted dibenzo‐α‐pyrones have been isolated. Their structures have been determined mainly using spectroscopic techniques. In the NMR. spectra of 1 and 4 and related model compounds an unusuallong‐range coupling over six bonds has been demonstrated.
Stereoselective Effects in Reactions of Metal Complexes, II selectivity in the complex formation of nickel(II)‐, copper(II)‐and zinc(II)‐(D)‐propylenediaminetetraacetate with racemic 1‐phenylethyl‐amine [1]
Authors: Bernauer K. , Jeanneret M.‐F. , Vonderschmitt D.
Published: December 2004

The selectivity in the formation of mixed complexes of optically active metapropylenediaminetetraacetates with 1‐phenylethyl‐amine has been investigated by chromatography and by liquid‐phase distribution measurements for the three metal ions Ni2+, Cu2+ and Zn2+. The selectivity is found to be sufficiently high to allow the chromatographic resolution of the racemic amine.
Préparation de quelques dérivés du nitro‐5‐thiophénecarbaldéhyde‐2
Authors: de Malleray Bernard Miche
Published: December 2004

Deux nitro‐thénylidéne‐oxazolones obtenues à partir du nitro‐5‐thiophénecarbaldéhyde‐2 ont été réduites et acétylétylées en une seule étape en méthyl‐2‐(acétylamino‐5‐thénylidène‐2)‐4‐oxazolone‐5 et en phényl‐2‐(acétylamino‐5′‐thénylidène‐2′)‐4‐oxazolone‐5 respectivement, déjà obtenues par une autre voice [1].
Note sur la préparation de l'acétylamino‐5‐acéty‐2‐thiophène
Authors: de Malleray Bernard Miche
Published: December 2004

L'acétylamino‐5 acétyl‐2‐thiophéne a été préparé avec un bon rendement par traitement de l'acéatylamino‐5‐thiophène (obtenu è partir du thiophéne par des procèdés connus) par Tanhydride acétique en présence de faibles quantités d'acide perchlorique.
ESR. Spectra of the Radical Anions of Cycloalkylbenzenes
Authors: Gerson F. , Moshuk G. , Schwyzer M.
Published: December 2004

Radical anions of five cycloalkylbenzenes (alkyl = propyl, butyl, pentyl, hexyl, or heptyl) have been studied by ESR. spectroscopy at −90°C. In the case of cyclopropylbenzene, no reliable experimental data could be obtained, because of the instability of its radical anion. The spectra of the radical anions of the four higher homologues have been analysed by means of a computer program. The assignment of the coupling constants to the α‐protons in the para position of the benzene ring and to the cycloalkyl ß‐protons has been based on the spectra of specifically deuterated derivatives.

The experimental data of the radical anion of cycloalkylbenzenes have been compared with those of the radical anions of five alkylbenzenes (alkyl = methyl, ethyl, n‐propyl, isopropyl, or t‐butyl), the spectra of the latter being reexamined at −90°C. In the cycloalkyl series the degeneracy of the two benzene‐type lowest antibonding orbitals is the more effectively removed the larger the substituent, whereas the reverse relation holds for the non‐cyclic series. The preferred conformation of the substituents is that in which the alkyl or cycloalkyl ß‐proton is near to the nodal plane of the benzene π‐system, and this preference is accentuated with the increasing size of the substituent group.
Photoelectron‐Spectroscopic Evidence for the Orbital Sequence in Fulvene and 3, 4‐Dimethylene‐cyclobutene
Authors: Heilbronner E. , Gleiter R. , Hopf H. , Hornung V. , De Meijere A.
Published: December 2004

The photoelectron spectra of fulvene (II) and of 3,4‐dimethylene‐cyclobutene (III) have been recorded. The PE. bands are correlated, in order of increasing ionisation potentials, with the following orbitals: II: 1a2(π), 2b1(π), 7b2(π), 1b1(π); III: 2b1(ω), 1a2(π), 10a1(ω), 8b2(ω), 1b1(π). This assignment is based on a semi‐quantitative perturbation MO‐model and on the SCF‐LCAO‐MO calculations reported by Praud, Millie & Berthier [5] for benzene, II and III.
Welkstoffe und Antibiotika. 39. Mitteilung [1]. Fusarinolsäure
Authors: Steiner K. , Graf U. , Hardegger E.
Published: December 2004

Das als Substanz H bezeichnete biologische Umwandlungsprodukt der Fusarinsäure (I) wurde als S(+)‐Fusarinolsäure (VIII) erkannt. Beweisend für die Konstitution VIII war die Umwandlung der Dehydrofusarinsäure (V) über die rac.‐Fusarinolsäure (Ia) in das (+)‐Fusarinolsäure‐(+)‐camphersulfonat (VIIIa), welches mit einem aus natürlicher (+)‐Fusarinolsäure (VIII) hergestellten Präparat identisch war. Die S‐Konfiguration der natürlichen (+)‐Fusarinolaäure ergab sich aus der Synthese von VIII bzw. VIIIa aus der Dinatriumverbindung VI des 2‐Carboxy‐5‐methyl‐pyridins and S(+)‐2‐Benzyloxy‐propyljodid (VIIa), welches konfigurativ mit der L‐Milchsäure verknüpft wurde.
Chemically Induced Dynamic Nuclear Polarization VIII: Thermal decomposition of dibenzoyl peroxides in solution [1]
Authors: Blank B. , Fischer H.
Published: December 2004

Thermolysis of di‐(4‐chlorobenzoyl)‐peroxide was carried out in the probe of an NMR. spectrometer. The dependence of product distribution and chemically induced dynamic nuclear polarization (CIDNP.) patterns on the concentrations of radical trapping agents gives evidence that the CIDNP. effects are caused by singlet‐triplet transitions, dependent on nuclear spin, in transient benzoyloxy/phenyl radical pairs and by the selective formation of radical products from singlet state pairs.
Synthèses dans la série des bis‐indéno‐anthracènes, II [1] Le dihydro‐9,16‐bis‐indéno[2.1‐α; 1′,2′‐c]anthracène
Authors: Chardonnens Louis , Schorderet François
Published: December 2004

Starting from 3,3′‐bi‐indenyle and 1,4‐naphthoquinone the title compound, III, has been synthesized in 3 steps (overall yield 54.6%).
Tetrakis‐triphenylphosphin‐platin(0), ein Katalysator zur selektiven Hydrosilylierung
Authors: Fink Walter
Published: December 2004

Tetrakis‐triphenylphosphine‐platinum(0) catalyses selectively the addition of silane to terminal olefinic double bonds. Neither hydrosilylation of internal double bonds nor isomerisations occur with this catalyst.
Synthese und Biologische Auswertung von 3β,20(R)‐Dihydroxy‐Protost‐24‐en
Authors: Immer H. , Huber K.
Published: December 2004

The possible lanosterol precursor, 3β, 20(R)‐dihydroxy‐protost‐24‐ene (1 a) has been prepared, in thirteen steps, from 3α‐hydroxy‐4α, 8, 14‐trimethyl‐18‐nor‐5α, 8α, 9β, 13ξ, 14β‐androstan‐17‐one (mixture of 2 and 3). In vitro experiments with rat liver homogenates failed to convert 1 a to lanosterol.
p‐Azido‐L‐phenylalanine: A photo‐affinity ‘probe’ related to tyrosine
Authors: Schwyzer Robert , Caviezel Mario
Published: December 2004

Synthese und Eigenschaften des p‐Azido‐L‐phenylalanins (1) und einiger seiner für die Peptidsynthese geeigneter Derivate werden beschrieben. Infolge der photolytischen Spaltbarkeit in Stickstoff und das Imen 2 dürfte dieses Analogon des Tyrosins als «photochemische Affinitätssonde» verwendbar sein.
The Competition between Spin Orbit Coupling and Conjugation in Alkyl Halides and its Repercussion on their Photoelectron Spectra
Authors: Brogli F. , Heilbronner E.
Published: December 2004

A crude molecular orbital model for alkyl halides is proposed, which provides a semi‐quantitative rationalization for the following experimental observations: (a) In the photoelectron spectra of alkyl halides RX (symmetry C8) the lone pair band is split into two components, separated by a gap Δ. This gap is equal to the splitting associated with spin‐orbit coupling in systems where X lies on a symmetry axis of order n ≥ 3. (b) The vibrational pattern of the two components indicates substantial conjugation between R and X. (c) Notwithstanding (b), the gap Δ is largely independent of the type of alkyl group R. (d) For strongly conjugating alkyl groups (e. g. R = cyclopropyl) the first component of the lone pair band (i. e. the one at lower ionization potential) broadens while the one at higher potential sharpens up.
Organic Phosphorus Compounds 52. Preparation and properties of β‐hydroxyalkyl‐phosphonium salts and tertiary phosphine oxides
Authors: Maier Ludwig
Published: December 2004

The new, tris‐ (2‐ hydroxyalkyl) ‐ (hydroxymethyl) ‐ phosphonium salts: [(RCHOHCH2)3PCH2OH]Cl (I, R = ClCH2; III, R = CH3) are formed in high yield by reaction of tetrakis‐(hydroxymethyl)‐phosphonium chloride (Tetrakis) with epoxides under basic conditions. Under the same conditions, styrene oxide yields only the disubstituted product, [(PhCHOHCH2)2(CH2OH)2P]Cl. Optimal pH values for the reactions are 8 to 9; at lower pH the conversion is too slow; at a higher pH, oxidative decomposition of the salts occurs. Conversion of the salts to tertiary phosphine oxides (RCHOHCH2)3P  O (R  ClCH2; CH3) with loss of the hydroxymethyl group is best carried out with chlorine at pH 5 to 7. The yields are usually 60 to 90%.
Réactions d'élimination présentées par des acides polyhydroxyadipiques
Authors: Gabbai A. , Posternak Th.
Published: December 2004

The tetrahydroxyadipic acids and one trihydroxyadipic acid have been methylated, using methyl iodide and silver oxide in the presence of dimethylformamide.

In addition to Δ2‐di‐ or tri‐methoxyadipic esters and the products expected for a double E2 elimination, cis‐trans α, α'‐dimethoxymuconic ester was frequently the principal product. The proposed theoretical interpretations involve as intermediates either a silver complex or a lactonic compound. A few preferential conformations, based on NMR. data, are proposed.
Protonierung von Purin, Adenin und Guanin NMR.‐Spektren und Strukturen der Mono‐, Di‐ und Tri‐Kationen
Authors: Wagner R. , Von Philipsborn W.
Published: December 2004

Proton NMR. spectra of purine, adenine, guanine and methylsubstituted guanines have been measured in CF3COOH, FSO3H and FSO3HSbF5SO2 at 27° and low temperatures. These conditions permit to study multiple protonation of purines, using chemical shifts of CH, NH and OH protons. The spectra of mono‐, di‐ and tri‐cations are described and fully assigned.
On the correlation between photoelectron and electronic spectra in trans‐ azomethane
Authors: Haselbach E. , Schmelzer A.
Published: December 2004

A possibility of correlating electronic and photoelectron spectra is discussed, using trans‐azomethane as an example. The Coulomb and exchange integrals required were obtained by three semi‐empirical SCF‐methods: MINDO/2, CNDO/2, and a modified CNDO method. The orbital energies were taken as minus the corresponding experimental ionization potentials. The sequence of the transition energies ΔE (ns → π*) Δ E (na → π*) < ΔE (π → π*) is found to be different from the ionization potential sequence IP (ns) < IP (π) < IP (na), in agreement with previous spectroscopic studies; the results support the latest view that the π → π* transition of the azo group occurs at around 12 eV.
Isomérisations en chimie des sucres. II Fermetures de cycles par attaque nucléophile intramoléculaire sur des carbones sp2 à caractère électrophile: Furannoses hybridés sp2 en C3
Authors: Tronchet J. M. J. , Bourgeois J. M.
Published: December 2004

When heated with one equivalent of H2O, the 1,2: 5,6‐di‐O‐isopropylidene‐α‐D‐ribo‐ and ‐xylo‐hexofuranos‐3‐uloses loose one molecule of acetone and yield the 3, 6‐anhydro‐1, 2‐O‐isopropylidene‐α‐D‐ribo‐ and ‐xylo‐hexofuranos‐3‐ulose ketohydrols. The carbonyl group of the starting material seems to provide some kind of intramolecular electrophilic assistance to the hydrolysis of the 5, 6‐O‐isopropylidene group. When the oxygen of the carbonyl group is replaced by cyanomethylene, an analogous cyclisation takes place under base catalysis, provided that C6 bears a free hydroxyl group.
Hexamethyl‐2‐oxabicyclo [3.2.0] hepta‐3,6‐dien
Authors: Baumann B. C. , Rey M. , Markert J. , Prinzbach H. , Dreiding André S.
Published: December 2004

Substance X, one of the three compounds obtained upon heating 5, 6‐endo‐epoxy‐hexamethyl‐bicyclo[2.2.0]hex‐2‐ene (11) and previously postulated by Klaus et al. [10] to be 5‐acetyl‐pentamethyl‐bicyclo[2.1.0]pentene (9), is now shown to be hexamethyl‐2‐oxabicyclo[3.2.0]‐hepta‐3, 6‐diene (10) by reinterpretation and supplementation of the spectral data and by ozonization of the dihydro derivative 16, which yields 1‐acetoxy‐2‐acety‐1‐1, 2, 3, 4‐tetramethyl‐cyclo‐butane (17). It is concluded that the Claisen equilibrium in this system lies entirely on the side of the enol ether 10; even drastic LiAIH4 conditions cannot force a reversal (10 → 9). Tetracyanoethylene adds to the enolic double bond of 10 to form the cyclo‐adduct 19.
On the chirality of the cystine disulfide group: Assignment of helical sense in a model compound with a dihedral angle greater than ninety degrees using NMR. and CD
Authors: Ludescher Urs , Schwyzer Robert
Published: December 2004

Im synthetischen [2, 7‐Cystin]‐Gramicidin S ist der Cyclodecapeptid‐Ring mit einer Disulfidgruppe überbrückt. NMR.‐Untersuchungen zeigen, dass die Peptidkette der Verbindung (wie beim Gramicidin S) in der antiparallelen β‐Konstellation vorliegt. Auf Grund von Abschirmungs‐Effekten kann der Disulfid‐Brücke die P‐helikale Chiralität zugewiesen werden. In Molekel‐Modellen beträgt der dihedrale Winkel φ etwa 120°. Die P‐helikale Anordnung, verbunden mit |90°| < |φ| < 180°|, bedingt nach der Theorie von Linderberg & Michl einen negativen Rotationsbeitrag der langwelligsten asymmetrischen Absorptionsbande, was mit unseren CD.‐Versuchen nun erstmals experimentell bestätigt wird (λmin = 271,5 nm, Θ = ‐7550, Åthanol). Auch der theoretisch geforderte zweite Cotton‐Effekt mit umgekehrtem Vorzeichen kann bei dieser Modellverbindung gut beobachtet werden (λmax = 230 nm, Θ = +60870, Åthanol); allerdings sind in diesem Bereiche Beiträge von Peptid‐n → π*‐Übergängen nicht a priori auszuschliessen, was den diagnostischen wert dieser Bande vermindert.
Recherches dans la série des cyclitols XLII. Synthèses de cyclitols tout‐cis dérivés du cyclopentane; préparation des cyclopentane‐tétrol et ‐ pentol tout‐cis
Authors: Cocu F. G. , Posternak Th.
Published: December 2004

All‐cis cyclitols derived from cyclopentane have been prepared in two ways: (i) by LiAlH4 reduction of all‐cis epoxypolyos; (ii) by dimethyl sulfoxide treatment, in the presence of sodium hydrogencarbonate, of brominated derivatives containing a neighbouring benzoyloxy group; under these conditions, the halogen is replaced by a cis‐oriented hydroxyl group. Thus all‐cis cyclopentane‐tetrol and ‐pentol have been prepared; their configuration has been confirmed by NMR. spectroscopy.
Synthèse du méthanesulfonate de (pyrimidyl‐2)‐1‐(méthylène)‐(dioxy‐3, 4‐benzyl)‐4‐pipérazinium (Piribedil) marqué au 14C
Authors: Lintermans J. , Benakis A. , Herbert M. , Pichat L.
Published: December 2004

The synthesis of crystalline 1‐(2‐pyrimidyl)‐4‐(3, 4‐methylenedioxybenzyl)‐piperazin methanesulfonate (ET 495) labelled with 14C fixed on the piperazine nitrogen N(4) has been realized in five steps from barium carbonate 14C; Specific activity of the final product: 32,8 mCi/mmol (110 m̈Ci/mg); radiochemical purity: around 99%. The mass spectrum of the labelled compound is in agreement with the chemical structure and the labelling position expected.
Action de nucléophiles sur des sucres ramifiés cyanovinylidéniques: Addition conjuguée, stéréomutation, migration de doubles liaisons. Communication préliminaire
Authors: Tronchet J. M. J. , Bourgeois J. M.
Published: December 2004

When treated with a series of nucleophiles cis‐3‐cyanomethylene‐3‐deocy‐1,2:5,6‐di‐O‐isopropylidene‐α‐D‐ribo‐hexofurannose (1) may yield its trans isomer, a product of allylic isomerization or a product of conjugate addition, depending on the nature of the nucleophile. The configuration of the starting material is also important as shown by the differences in reactivity between 1 and its trans‐xylo isomer 8.
Mass Spectrometry and Organic Analysis, part 14. The photolysis and mass spectra of medium and large ring ketones from C9 to C16
Authors: Schulte‐Elte K. H. , Willhalm B. , Thomas A. F. , Stoll M. , Ohloff G.
Published: December 2004

The photolysis of cyclic ketones from C9 to C16 has been carried out, and formation of cyclobutanols observed in only C11 to C16. Although in the mass spectrometer cyclobutanols are not formed, an initial transfer of a γ‐hydrogen atom to the carbonyl group is shown to occur in the mass spectra of all cyclic ketones higher than C10.
Die Stereochemie der Irone
Authors: Rautenstrauch V. , Ohloff G.
Published: December 2004

The 6 R configuration of (+)‐cis‐γ‐irone [(+)‐4] was established by chemical correlation with (—)‐camphor. (+)‐cis‐γ‐irone [(+)‐4] was converted into (+)‐cis‐α‐irone [(+)‐1], (−)‐trans‐α‐irone [(minus;;)‐2], and (+)‐β‐irone [(+)‐3], which therefore also have the 6 R configuration. The 2 S configurations of (+)‐cis‐α‐irone [(+)‐1] and (+)‐trans‐α‐irone [(+)‐2] were determined by comparison of their circular dichroism with that of R‐α‐ionone [(+)‐5]. The 2 S configuration of (+)‐cis‐γ‐irone [(+)‐4] was established by chemical correlation with (+)‐cis‐α‐irone [(+)‐1].
„Nichtcarbenoide”︁ Zwischenstufen bei der Fragmentierung von α‐Cyclopropyltosylhydrazonen
Authors: Ohloff G. , Pickenhagen W.
Published: December 2004

The sodium salts of the tricyclic tosylhydrazones 1, 4 and 5 yield by base‐catalyzed fragmentation between 130–160° the monocyclic ring expansion products 2, 3 and 6. IR.‐spectrometry suggests a diazoalkane A as the principal intermediate of the fragmentation. Besides the known carbene mechanism the reaction is considered to pass through a noncarbenoid intermediate.
Darstellung von (+)‐ und (−)‐7‐Hydroxy‐dihydrocitronellal aus (+)‐Pulegon. Ein Beitrag zur Kenntnis olfaktorischer Eigenschaften von Enantiomeren
Authors: Skorianetz W. , Giger H. , Ohloff G.
Published: December 2004

The enantiomers of 7‐hydroxy‐dihydrocitronellal have been prepared stereo‐specifically from (+)‐pulegone by a sequence of analogous reactions. The olfactory properties of the final products and of the intermediates have been investigated. In most cases they exhibit remarkable qualitative and quantitative differences in odour.
Applications synthétiques de la cyclisation d'alcools tertiaires γ‐éthyléniques en α‐bromotétrahydrofurannes sous l'action du N‐bromosuccinimide. II. Cyclisation du (±)‐nérolidol en diméthyl‐2,5‐(méthyl‐4‐pentène‐3‐yl)‐2‐cycloheptène‐4‐one, tétraméthyl‐3, 3, 7, 10‐oxa‐2‐tricyclo[5.5.0.01,4]‐dodécène‐9, β‐acoratriène, cédradiène‐2,8, épi‐2‐α‐cédrène et α‐cédrène
Authors: Demole E. , Enggist P. , Borer Mlle C.
Published: December 2004

The ionic reaction of (±)‐nerolidol (cis/trans mixture) with N‐bromosuccinimide in CCI4 at room temperature afforded 2‐methyl‐2‐vinyl‐5‐(2‐bromo‐6‐methyl‐hept‐5‐en‐2‐yl)‐tetrahydrofuran (4) in high yield. This compound was readily dehydrobrominated by refluxing collidine to the intermediate allyl vinyl ether 8, which immediately undergoes [3,3]‐sigmatropic rearrangement to 2, 5‐dimethyl‐2‐(4‐methylpent‐3‐enyl)‐cyclohept‐4‐enone (11). By treatment with SnCI4 in nitromethane at room temperature 11 was in turn cyclised to cis‐3, 3, 7, 10‐tetramethyl‐2‐oxa‐tricyclo[5.5.0.01,4]dodec‐9‐ene (12), an oxetane closely related to the sesquiterpene carotol. This oxetane (12) underwent a stereospecific ring contraction when treated by Lewis acids such as H2AICI or HAlCI2, to form the β‐acoratriene (13).Finally, the BF3‐catalysed cycli‐ sation of the latter afforded 2,8‐cedradiene (19) from which 2‐epi‐α‐cedrene (20) was easily obtained by partial, regio‐selective hydrogenation. α‐Cedrene (22) itself, together with its epimer 20, resulted from the Wolff‐Kishner reduction of the 2‐epi‐α‐cedren‐3‐one (21), prepared by selective hydroboration/oxidation of 19.

A transformation of nerolidol to α‐cedrene was thus achieved by a unique stepwise cyclisation process.
Recherches sur les arǒmes. 17e communication. Sur l'arǒme de framboise, IV
Authors: Winter M. , Enggist P.
Published: December 2004

The neutral fraction of medium volatility from raspberry oil has been analysed by gas chromatography and mass spectrometry. From the large number of constituents thirtynine have been identified, 24 of them for the first time, including dihydro‐β‐ionone (I), epoxy‐β‐ionone (II), damascenone (III)1, theaspirane (IV) and 2‐hexen‐4‐olide (V). According to these results raspberry oil consists mainly of alcohols, ketones, aldehydes and lactones.
Eine neue Synthese von 3,6‐Dialkyl‐1,2,4,5‐tetrazinen
Authors: Skorianetz W. , Sz. Kováts E.
Published: December 2004

A new synthesis of 3,6‐dialkyl‐1,2,4,5‐tetrazines (or ‐s‐tetrazines), 4, is described (see reaction scheme [1→2→3→4]). The 3,6‐dialkyl‐hexahydro‐s‐tetrazines, 2, R = n‐alkyl, are readily available by the reaction of fatty aldehydes and hydrazine. s‐Tetrazines with branched substituents and mixed alkyl‐s‐tetrazines can also be prepared by the same procedure, however, in lower yields.
Stereospecific Olefin Synthesis via Lithium Vinylcuprates
Authors: Näf F. , Degen P.
Published: December 2004

The conjugate addition of cis‐ or trans‐1‐alkenyl‐cuprolithium complexes (RCHCH)2CuLi · Xn

R  alkyl, X  ligands such as ether, tetrahydrofuran, (CH3O)3P and (n‐Bu)3P. Physical studies to determine the structure of these copper reagents are in progress, see footnote 20 of reference [1].

to α, β‐unsaturated carbonyl compounds was found to occur with high retention of double bond geometry, affording isomerically pure cis‐ or trans‐γ, δ‐ethylenic carbonyl compounds. The same 1‐alkenylcuprates also react stereospecifically with alkyl halides to give isomerically pure cis‐ or trans‐olefins.
Le mécanisme de l'hydrolyse acide des aryl‐diazométhanes
Authors: Dahn H. , Diderich G.
Published: December 2004

In the acid catalysed hydrolysis of three monoaryl‐diazomethanes (p)‐nitrophenyl‐diazométhane (I),p‐chlorophenyl‐diazomethane (II), phenyl‐diazomethane (III), absence of exchange H‐D, solvent isotope effects about 2,6, and general acid catalysis prove that proton transfer is rate determining (A‐SE2 mechanism). Like otherA‐SE2 reactions, the hydrolysis of I is shown to obey theBrønstedcatalysis law with a variety of carboxylic acids; for eight of these acids, αBwas found to be 0,69 ± 0,06.
Umsetzung von 3‐O‐Acetyl‐14‐anhydrodigitoxigenin und 3‐O‐Acetyldigitoxigenin mit Osmiumtetroxid
Authors: Schüpbach M. , Krasso A. F. , Binder M. , Tamm Ch.
Published: December 2004

Treatment of 3‐O‐acetyl‐14‐anhydrodigitoxigenin (1) with 1.1 equivalents of OsO4 gave both the 14α, 15α‐diol 2 and the 14β, 15β‐diol 4. Degradation to the corresponding methyl etianates 7 and 10, respectively, established their stereochemistry. Treatment of both the 14‐hydroxy‐15‐acetoxy‐cardenolides 3 and 5 with OsO4 leads to the expected mixtures of 20, 22‐diols, a partial separation of which was achieved after acetylation. The butenolide ring of 3‐O‐acetyl‐digitoxigenin (25) also reacted with OsO4, yielding the two 20,22diols 26 and 27, the stereochemistry of which has tentatively been assigned on the basis of NMR. data.
Nitration of Durene and Pentamethylbenzene with Nitronium Salts in Nitromethane and Acetonitrile
Authors: Hunziker E. , Penton J. R. , Zollinger H.
Published: December 2004

Nature and proportions of the products formed in the nitrations mentioned in the title are affected by the process of mixing.

Pentamethylnitrobenzene, formed initially in the nitration of pentamethylbenzene, is attacked by a nitronium ion at a position meta to the nitro‐group. In the σ‐complex formed, loss of a proton from a methyl group leads to production of by‐products and release of nitrite ions. The nitrous acid formed is protonated, and water is displaced from the nitrous acidium ion by the anion, PF6⊖, giving the nitrosonium ion which forms a 1:1 symmetric molecular complex with pentamethylbenzene. A similar complex is formed in the reaction between durene and nitronium salts.

The results are consistent with the view that no σ‐bond is formed between the aromatic compound and the nitrosonium ion.
Synthese von 2‐Thia‐6‐aza‐adamantan und Derivaten
Authors: Ganter C. , Portmann R. E.
Published: December 2004

The synthesis of 2‐thia‐6‐aza‐adamantane (19) and several of its derivatives was achieved starting from 9‐azabicyclo[3.3.1]nona‐2,6‐diene (9) which was prepared from cis, cis‐cycloocta‐1, 5‐diene (1). Transannular addition of sulfur dichloride to its N‐benzenesulfonyl and N‐formyl derivatives 10 and 11 yielded the tricyclic dichlorides 12 and 13, respectively; the 2‐thia‐6‐aza‐adamantanes 14–19 were synthesized from 13.
2β, 13‐Oxido‐apotrichothecane: Synthese, chemische und physikalische Eigenschaften. Verrucarine und Roridine, 23. Mitteilung
Authors: Schumacher R. , Gutzwiller J. , Tamm Ch.
Published: December 2004

Starting from the 12,13‐epoxy‐trichothecanes roridin C (trichodermol) (1), verrucarol (15) and trichothecolone (25), the isomeric 2β, 13‐epoxy‐apotrichothecanes 9, 20 and 33 have been synthesized. In these compounds the oxetane group proved to be unexpectedly stable to mineral acids and complex metal hydrides, probably due to its fusion to a cyclopentane ring. The IR. and NMR. spectra of the oxetanes are discussed.
Tetrajodterephtalsäure‐derivate als Röntgen‐Kontrastmittel
Authors: Suter H. , Zutter H. , Brunner J.
Published: December 2004

New monoamides and diamides of tetraiodoterephthalic acid have been synthesized for evaluation as X‐ray contrast agents. Solubility, toxicity, bilitropism, urotropism, and in some cases cholecystographic quality of these compounds are given.
Steroid Total Synthesis, Part II; (−)‐17β‐Hydroxy‐des‐A‐androst‐9‐en‐5‐one
Authors: Saucy G. , Borer R.
Published: December 2004

Based on the results obtained in the racemic series (part I), (—)‐17β‐hydroxy‐des‐A‐androst‐9‐en‐5‐one has been synthesized, starting with (S)‐(—)‐5‐heptanolide. The key step, viz. the condensation of (S)‐(—)‐7‐hydroxy‐1‐nonen‐3‐one (or its amine adduct) with 2‐methyl‐cyclopentane‐1, 3‐dione involves an asymmetric induction. Model experiments with (R)‐(+)‐5‐decanolide leading to the enantiomeric homolog of the BCD‐tricyclic compound are also described.
Dérivés de nucléotides d'intérêt biologique VIII. Synthèse de quelques analogues de l'acide adénosine‐triphosphorique (ATP)
Authors: Gabbai A. , Marcus I. , Falbriard J. G. , Posternak Ht.
Published: December 2004

Analogues of ATP belonging to the following classes have been prepared: N6‐monoacyl derivatives, N6‐mono‐ and ‐di‐alkyl derivatives, 6‐deamino‐ATP, 8‐bromo‐ATP, 8‐amino‐ATP and ATP‐N(1)‐oxide. With the exception of the last compound, the corresponding AMP derivatives have been used as intermediates in these preparations.
Dérivés de nucléotides d'intérêt biologique, IX. Essais enzymatiques avec des analogues de l'acide adénosine‐triphosphorique (ATP). Communication préliminaire
Authors: Gabbai A. , Posternak Ht.
Published: December 2004

The reactivity, as substrates for hexokinase and glycerokinase, of some analogous of ATP has been compared with that of ATP.
Photochemische Reaktionen. 66. Mitteilung. UV.‐Bestrahlung von 11‐Oxo‐Steroiden IV Neuartige Photoisomerisierung von 3,20‐Di‐äthylendioxy‐11‐oxo‐δ14‐5α‐pregnen
Authors: Gull P. , Wehrli H. , Jeger O.
Published: December 2004

UV. ‐irradiation of the 11‐oxo‐δ14‐5α‐pregnene derivate 16 gives rise to a novel photochemical reaction. The preferential attack of the photochemically excited carbonyl on CH‐8 furnishes the tertiary cyclopropanol compound 18 in high yield.
Die oxydative Anlagerung von Methyldichlorsilan an Tetrakis‐(triphenylphosphin)‐platin(0)
Authors: Fink Walter , Wenger Adrian
Published: December 2004

By oxydative addition of methyldichlorosilane to tetrakis‐(triphenylphosphine)‐platinum(0) three types of silicon‐platinum complexes are formed.
Etude par analyse thermique différentielle des transformations ordre‐désordre dans des alliages or‐cuivre riches en or
Authors: Lüthy H. , Isler C. , Tissot P.
Published: December 2004

By differential thermal analysis of some Au‐Cu alloys the order‐disorder transformation AuCu IAuCu II of the compound AuCu is shown to be a first order transformation accompanied by a variation of enthalpy. This method has also allowed to detect a certain order in alloys with more than 75 at‐% Au.
The Identity of the gamma Modification of Basic Lead Azide Type I
Authors: Todd G. , Tasker M. P.
Published: December 2004

Published information on the basic lead azide series is discussed with particular reference to the gamma modification of basic lead azide I. A sample of this product has been prepared and the absence of significant impurity confirmed by X‐ray diffraction analysis. Infrared absorption analysis has indicated the presence of PbO bonding and the absence of HO bonding. The product is therefore an oxyazide containing neither hydroxide nor water of crystallisation. Chemical analysis confirms that the Pb(N3)2:PbO ratio is less than one.
Synthese, Struktur und Reaktionen von Secosteroiden mit einem mittleren Ring V. Photochemische Cyclisation von cis‐ und trans‐3β‐Acetoxy‐5‐oxo‐Δ1(10)‐5, 10‐secocholesten
Authors: Mihailović M. Lj , Lorenc Lj. , Popov N. , Kalvoda J.
Published: December 2004

In continuation of our work on transannular cyclizations of trans‐3β‐sacetoxy‐5, 10‐seco‐cholest‐1 (10)‐en‐5‐one (1), the ringclosure of this compound and of its cis‐isomer (11) under UV.‐irradiation was examined: both yield the same mixture of oxetanes 2 and 3 exhibiting the natural steroid skeleton.
Photochemisches Verhalten von 1‐ und 2‐alkylierten 1,2‐Dihydronaphtalinen
Authors: Heimgartner H. , Ulrich L. , Hansen H. ‐J. , Schmid H.
Published: December 2004

Irradiation of 1‐alkyl‐substituted 1,2‐dihydronaphthalenes (10, 11, 12) with a lowpressure mercury lamp yields by ring opening ω‐vinyl‐o‐quinodimethanes, which undergo [1, 7] H‐shifts to give 1,2‐divinyl‐benzenes (8, 18, 23; cf. schemes 2, 3 and 4). In a further photoreaction of the divinylbenzenes, benzobicyclo [3.1.0]hex‐2‐enes (17, 19, 22) are formed. 2‐Alkyl‐substituted 1,2‐dihydronaphthalenes (13, 14, 15, 16) are transformed by irradiation into ω‐vinyl‐o‐quinodimethanes, which show [1, 7] H‐shifts to yield in this case 2‐(buta‐1′, 3′‐dienyl)‐toluenes (9, 25, 26, 27; cf. schemes 6 and 7). The irradiation of 1‐methyl‐ (10) and 1‐ethyl‐1, 2‐dihydronaphthalene (11) with a high‐pressure mercury lamp produces, besides the products of irradiation using the lowpressure lamp, 2‐ethyl‐allenylbenzene (24), and (from 11) 4‐exo‐ethyl‐benzobicyclo[3.1.0]hex‐2‐ene (exo‐20) and 2‐propyl‐allenylbenzene (21), respectively (cf. scheme 5). Obviously, these products arise from a photreaction of the primarily formed ω‐vinyl‐o‐quinodimethanes a.