bluuebunny/crossref_metadata_2025_split huggingface dataset:
4‐Azidoaniline, a Versatile Protein and Peptide Modifying Agent for Photo Affinity Labeling
Authors: Escher Emanuel H. F. , Robert Hélène , Guillemette Gaétan 
Published: December 2004

AbstractA modified synthesis of 4‐azidoaniline and the use of this compound as a protein and peptide modifying agent for photoaffinity labeling is described. 4‐Azidoaniline was diazotized to 4‐azidophenyldiazonium and coupled to N‐acetyl‐tyrosine‐ethylester, and to a tyrosine containing analog of bradykinin.It is shown that the 4‐azidoaniline reagent offers great advantages over other protein modifying agents for photoaffinity labeling, i.e., very high nitrene reactivity, possibility of tritium or iodine labeling, ligand‐receptor complex can be cleaved after isolation. The biological activity of the modified bradykinin analog is measured on rabbit aorta strip in the dark and is similar to the unsubstituted analog. Under the influence of light the modified peptide is able to block partially the myotropic action of bradykinin.
Synthese und Konfiguration einiger Spiro [indan‐2,2′‐pyrrolidin]‐ und Spiro [pyrrolidin‐2,2′‐tetralin]‐Derivate,
Authors: Stoll André P. , Petcher Trevor James , Weber Hans Peter 
Published: December 2004

Synthesis and configuration of some spiro [indan‐2,2′‐pyrrolidine] and spiro [pyrrolidine‐2,2′‐tetraline] derivativesCatalytic hydrogenation of the nitrosoindan and nitrosotetralin derivatives 8 yielded trans‐1‐hydroxy‐spiro [indan‐2,2′‐pyrrolidin]‐5′‐one (9) and trans‐1′‐hydroxy‐spiro [pyrrolidine‐2,2′‐tetralin]‐5‐one (10) respectively, whilst the corresponding cis compounds 12 and 15 were prepared via the chlorides 11 and 14.The configurations of 10 and 13 were determined by X‐Ray analysis.
Über die Synthese des Muscaflavins. Vorläufige Mitteilung,
Authors: Barth Hubert , Kobayashi Makoto , Musso Hans 
Published: December 2004

Synthesis of muscaflavinA biomimetic type synthesis of the yellow dihydroazepine amino acid 5 isolated from fly agaric is achieved starting with carboxypyridyl alanine derivatives.
Cynaratriol, ein neues Guajanolid aus der Kardone Cynara cardunculusL. und der Artischocke C. scolymusL.(Compositate)
Authors: Bernhard Heinz O. , Thiele Kurt , Pretsch Ernö 
Published: December 2004

Cynaratriol, a new guajanolide from Cynara cardunculus L. and C. scolymus L. (Compositae)A new guajanolide given the name cynaratriol (4) was isolated from the leaves of Cynara cardunculus L The structure of 4 and its derivatives 3, 11, 13‐triacetylcynaratriol (5) and 3, 13‐dibenzoyl‐cynaratriol (6) was deduced on the basis of IR.‐, 1H‐NMR.‐, 13C‐NMR.‐ and mass spectroscopic data. 4 is also present in C. Scolymus L. as shown by GC./MS. analysis. The same absolute configuration is suggested for 4 as found for all other Cynara sesquiterpenes.
On the Claisen Rearrangement of Allyl Ethyl Ketene Acetals Generated in situ via Benzeneselenenic Acid Eliminiation
Authors: Pitteloud Rita , Petrzilka Martin 
Published: December 2004

AbstractMixed acetals 7 of benzeneseleninylacetaldehyde, prepared by a simple 2‐step procedure from mono‐ and bicyclic allylic alcohols 5, undergo benzeneselenenic acid elimination to transient ketene acetals 8 which afford γ, δ‐unsaturated esters 9 via the ester Claisen rearrangement (Scheme 2). Under the same conditions selenoxide 7h derived from benzyl alcohol 5h is converted back to benzyl alcohol with the concomitant formation of ethylphenylselenoacetate 12.
Zur Biogenese der Betacyane: Versuche mit [2‐14C]‐Dopaxanthin
Authors: Wyler Hugo , Meuer Ursula 
Published: December 2004

On the biogenesis of betacyanins. Expaiments with [2‐14C]‐dopaxanthineLabelled dopaxanthine is prepared from betanin by a double exchange procedure replacing first its cyclodopa part by diethylamine and effecting the second exchange with 2‐[14C]‐dopa on the purified intermediate ‘DEA‐betalain’; the specific activity delivered with the dopa allowed accurate determination of ϵ in the electronic spectrum of dopaxanthine (λmax 488 nm, ϵ = 41.800). The C(2)‐labelled dopaxanthine is incubated into the fruits of Opuntia bergeriana. The incorporation rates into betanin are found to correspond approximately to those obtained in earlier experiments with labelled dopa alone: Only 1‐‐5% of the label showed up in the cyclodopa moiety of the betanin (which is isolated as cyclodopa‐glucoside) whereas 99‐‐95% of the radioactivity was associated with the betalamic acid part (recovered in form of indicaxanthine).
The Radical Anions of 5,5′‐ and 6,6′‐Biazulenyl
Authors: Gerson Fabian , Lopez Javier , Metzger André , Jutz Christian 
Published: December 2004

AbstractESR. and, in part, ENDOR. studies are reported on the radical anions of 5,5′‐and 6,6′‐biazulenyl (1 and 2, resp.), as well as on their 1, 1′, 3, 3′‐tetradeuterioderivatives (1‐d4 and 2‐d4). The reduction processes of 1 and 2 leading to these radical anions (\documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ 2^{\ominus \atop \dot{}}$\end{document}) and the dianions (
equation image
) have been investigated by polarography and cyclic voltammetry. The half‐wave reduction potential of 1 and the π‐spin distribution in \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}}$\end{document} are consistent with the model of two weakly interacting azulene π‐systems, whereas the analogous findings for 2 and \documentclass{article}\pagestyle{empty}\begin{document}$ 2^{\ominus \atop \dot{}}$\end{document} point to a strong interaction between two such systems. This difference can be traced to the distinct inequality ∥c65 ∥ « ∥ c66 ∥ in the LCAO coefficients c6μ at the centres μ=5 and 6 for the LUMO Ψ6 of azulene.
The Radical Ions of Naphtho [1,8‐cd]‐[1,2,6]thiadiazine and Some of Its Derivatives
Authors: Gerson Fabian , Plattner Georges , Bartetzko Richard , Gleiter Rolf 
Published: December 2004

AbstractThe radical cations and anions of naphtho [1,8‐cd]‐[1,2,6]thiadiazine (1) and 6,7‐dihydroacenaphtho [5, 6‐cd]‐[1,2,6]thiadiazine (2), as well as the radical anion of acenaphtho [5, 6‐cd]‐[1,2,6]thiadiazine (3) have been characterized by ESR. spectroscopy. The π‐spin distributions in the radical cations \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\oplus \atop \dot{}}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ 2^{\oplus \atop \dot{}}$\end{document} strongly resemble those in the iso‐π‐electronic phenalenyl radical. A prominent feature of the radical anions \documentclass{article}\pagestyle{empty}\begin{document}$ 1^{\ominus \atop \dot{}}$\end{document}, \documentclass{article}\pagestyle{empty}\begin{document}$ 2^{\ominus \atop \dot{}}$\end{document} and \documentclass{article}\pagestyle{empty}\begin{document}$ 3^{\ominus \atop \dot{}}$\end{document} is the substantial localization of the π‐spin population on the thiadiazine fragment. These findings are satisfactorily accounted for by HMO models using conventional heteroatom parameters.
Conversion of Amines into Phenylsulfides and Phenylselenides via Ditosylamides
Authors: Müller Paul , Thi Minh Phuong Nguyen 
Published: December 2004

AbstractAmines are converted in good to excellent yields to phenylsulfides or phenyl‐selenides via nucleophilic displacement on the corresponding ditosylamides. The conversion of (−)‐(S)‐1‐phenylethylamine to the chiral phenylsulfide 6 was found to proceed with inversion of configuration. A simple one‐pot procedure for the preparation of ditosylamides is reported.
Stereochemistry of the Conversion of 1,3‐Chloroalcohols in Alkaline Medium. The Chemistry of 1,3‐Bifunctional Systems. XXII
Authors: Bartók Mihály , Felföldi Károly , Bozöki‐Bartók Gizella 
Published: December 2004

AbstractThe transformations of isomeric 1,3‐chloroalcohols 1–4, with cyclohexane skeleton, were studied in aqueous solution containing barium hydroxide. As regards the compounds with cis‐configuration, 1 gives the oxetane 5 by intramolecular nucleophilic substitution, while 3 gives the unsaturated alcohols 7 and 8 by elimination. In the case of the trans‐isomers 2 and 4, fragmentation reactions occur in competition with elimination. The main reaction kinetic parameters of the transformations of the four compounds were determined.
Photochemische Reaktionen 115. Mitteilung [1]. Zur Photochemie konjugierter γ,δ‐Epoxyenone: Der Einfluss eines Hydroxylsubstituenten in ϵ‐Stellung
Authors: Nakamura Norio , Schweizer Wolfhard Berned , Frei Bruno , Wolf Hans Richard , Jeger Oskar 
Published: December 2004

Photochemistry of Conjugated γ,δ‐Epoxyenones: The Influence of a Hydroxy Substituent in ϵ‐PositionOn 1n, π*‐ or 1π,π*‐excitation (λ ≥ 347 or λ=254 nm), the ϵ‐hydroxy‐γ;,δ‐epoxyenone 8 undergoes fission of the C(γ)O bond followed by the cleavage of the C(δ)‐C(ϵ) bond. This hitherto unknown sequence of reactions is evidenced by the structure determination of the new type products 10–17 and 25, including a synthetic proof for 12 and the X‐ray analysis of 11 (X‐ray data: triclinic P1; a=7,386(2), b=8,904(4), c=9,684(5)Å; α=82,29(4)°, β=74,46(3)°, γ=82,29(3)°; Z=2).The selective 1π,π*‐excitation also induces competitive C(γ)‐C(δ) bond cleavage to yield the bicyclic acetal 18 and a ketonium‐ylide intermediate a, which photochemically forms a carbene b giving the allene 19 and the cyclopropene 20.On 1n,π*‐excitation of the acetate 9 the initial C(γ)‐O bond fission is, in contrast to the behaviour of the corresponding alcohol 8, followed by a 1,2‐methyl shift affording (E/Z)‐28 or by a cyclization‐autoxidation process yielding the lactone 29.
Lipophilic Amides of EDTA, NTA and Iminodiacetic Acid as Ionophores for Alkaline Earth Metal Cations
Authors: Erne Daniel , Stojanac Nada , Ammann Daniel , Pretsch Ernö , Simon Wilhelm 
Published: December 2004

AbstractA series of electrically neutral lipophilic di‐, tri‐, and tetra‐amides containing tertiary‐amine N‐atoms were prepared in order to investigate their selectivity for alkali and alkaline earth metal cations in solvent polymeric membranes. Considerable selectivity changes were observed for membranes incorporating certain of these ligands as compared with ligand‐free membranes. A 1:1 cation/ligand complex was isolated from N, N′, N″‐triheptyl‐N, N′, N″‐trimethyl‐nitrilotriacetamid and Mg (SCN)2 whereas with Ca (SCN)2 the corresponding 2:3 cation/ligand complex was formed. N, N′, N″, N‴, N‴‐tetramethyl‐ethylenediaminetetraacetamide yields a 1:1 cation/ligand complex with Mg (SCN)2.
Beitrag zur massenspektrometrischen retro‐Diels‐Alder‐Reaktion: 1,2,3,4‐Tetrahydrophenanthren. 35. Mitteilung über massenspektrometrische Untersuchungen
Authors: Huggenberg Sonja , Hesse Manfred 
Published: December 2004

Contribution to the Mass Spectral retro‐Diels‐Alder Reaction: 1,2,3,4‐Tetrahydrophenanthrene[1,4‐13C]‐1,2,3,4‐Tetrahydrophenanthrene (1) was synthesized starting from [1,4‐13C]‐succinic acid. The mass spectral behavior (EI./MS., 70eV) of 1 is very similar to that of tetraline [2] concerning its loss of ethylene from the molecular ion. Similarly the fragmentation reaction of the synthetic precursors, ketones 7 and 8, seems to partly undergo a carbon rearrangement reaction prior to the elimination of ethylene which is unlike to the behavior of α‐tetralone.
Steroids and sex hormones. Part 262. The radical induced stannane reduction of selenoesters and selenocarbonates: A new method for the degradation of carboxylic acids to nor‐alkanes and for desoxygenation of alcohols to alkanes
Authors: Pfenninger Johannes , Heuberger Christoph , Graf Walter 
Published: December 2004

AbstractEsters of carboselenoic acids, formed from carboxylic acids by conventional methods, undergo reaction with tributyltin hydride in inert aromatic solvents, either by heating to give the corresponding aldehyde or the corresponding alkane depending on reaction temperature and the structure of the parent carboxylic acid, or by ultraviolet irradiation at ambient temperature when the aldehyde is formed predominantly in high yield. In the case of esters of α, β‐unsaturated carboselenoic acids the thermal reaction leads only to the corresponding aldehyde.The above stannane reduction can also be applied to selenocarbonates of primary and secondary alcohols (prepared from the corresponding chloroformates), to give the alkane, the parent alcohol and the corresponding formate, in relative amounts depending on the reaction temperature.These reactions thus constitute preparatively useful and high‐yield degradation methods compatible with the presence of many other functional groups.
Steroids and sex hormons. Part 264. Lewis acid catalyzed reversible [1,5]‐hydride shift in 3,19‐epoxy‐steroids
Authors: Acklin Georg , Graf Walter 
Published: December 2004

Abstract3β, 19‐Epoxy‐3 α‐methoxy‐steroids (e.g. 1, Scheme 1) are converted into the corresponding 3 α‐methoxy‐19‐oxo compounds (e.g. 3) in the presence of boron trifluoride etherate, via an intramolecular hydride ion transfer from C (19) to (3) which is shown to be an equilibrium process. By subjecting the specifically deuteriated (19 S)‐ and (19 R)‐compounds 1b and 1c to this reaction it was shown to be highly stereoselective.
Synthesis of Pure Al35Cl3 and Al37Cl3
Authors: Geiser Urs , Schmidhalter Beat , Schumacher Ernst 
Published: December 2004

AbstractChemically and isotopically pure Al35Cl3 and Al37Cl3 are synthesized from Al (s) and HCl (g). The yield is quantitative and no measurable decrease in isotopic content from HCl to AlCl3 takes place.
Photochemical reactivity of α,β‐unsaturated δ‐lactams: Synthesis of seco‐steroids. Photochemical reactions. XIII [1]
Authors: Cánovas Antonio , Fonrodona Jesús , Bonet Juan‐Julio , Briansó Marie Claire , Briansó José Luis 
Published: December 2004

AbstractThe UV. irradiation of 17 β‐hydroxy‐2‐aza‐4‐androsten‐3‐one (1), N‐methyl‐17 β‐hydroxy‐2‐aza‐4‐androsten‐3‐one (3), 17 β‐hydroxy‐4‐aza‐5 β‐androst‐1‐en‐3‐one (2) and N‐methyl‐17 β‐hydroxy‐4‐aza‐5 β‐androst‐1‐en‐3‐one (4), gives rise to 1,10‐seco (from 1 and 3) and 5, 10‐seco (from 2 and 4) steroids.
Die Strukturdynamik von Pentadienylmetall‐Verbindungen mit endständiger Alkyl‐Gruppe: zugleich «stereoselektive» und «stereodefensive» Synthese eines natürlichen Riechstoffes
Authors: Bosshardt Herbert , Schlosser Manfred 
Published: December 2004

Structural Dynamics of Pentadienyl Metal‐Compounds Bearing a Terminal Alkyl Substituent: Both ‘Stereoselective’ and ‘Stereodefensive’ Synthesis of a Natural Perfume.The (2Z, 4E)‐, (2E, 4Z)‐ and (2E, 4E)‐isomers of 2,4‐decadien‐1‐ol (5) have been obtained with high and predictable stereochemical homogeneity starting from both (Z)‐ and (E)‐1, 4‐decadiene. These hydrocarbons were hydroxylated in a reaction sequence consisting of metallation (by means of s‐butyllithium or butyllithium/potassium‐t‐butoxide, giving rise to organometallic intermediates of specific conformation), dimethoxyborylation and oxidation. The different decadienols as well as (2E, 4Z)‐2, 4‐undecadien‐1‐ol were converted into the isovalerates, the ester derived from (2E, 4Z)‐2, 4‐decadien‐1‐ol being a natural flavor component.
π‐Bond Configurations, Conformations, and Dynamic Behaviour of Benzo[c]octalene and Dibenzo[c,j]octalene
Authors: Oth Jean F. M. , Müllen Klaus , Schmickler Hans , Engels Hans‐Wilhelm , Vogel Emanuel 
Published: December 2004

AbstractThe π‐bond configurations, the conformations, and the dynamic behaviour of dibenzo [c,j]octalene (2) and of benzo [c]octalene (3) have been investigated by 13C‐NMR. spectroscopy at different temperatures. Dibenzooctalene was found to present π‐bond fixation in the octalene unit as in 2b; with this π‐bond fixation the molecule is not planar and takes two different conformations which are rapidly interconverted by inversion of one cyclooctatetraene ring. Monobenzooctalene (3) also presents π‐bond fixation in the octalene unit but exists as two valence isomers, 3b and 3c. Isomer 3c dominates the dynamic equilibrium. With this π‐bond configuration, the molecule is chiral but undergoes several isodynamic processes, namely inversion of the cyclooctatriene and/or of the cyclooctatetraene ring. The valence isomer 3b can have two different conformations which are rapidly interconverted by inversion of one cyclooctatetraene ring. The interconversion 3c ⇌ 3b implies the occurrence of a π‐bond shift process; this process affects the 13C‐NMR. lineshape above 50°.
Nucleoside und Nucleotide. Teil 14. Synthese des Octanucleosidheptaphosphats d(G‐A‐T‐T‐T‐T‐G‐A)
Authors: Bühlmayer Peter , Graf Georg , Waldmeier Felix , Tamm Christoph 
Published: December 2004

Nucleosides and Nucleotides. Part 14. Synthesis of the Octanucleosideheptaphosphate d(G‐A‐T‐T‐T‐T‐G‐A)The synthesis of the oligonucleotide d(G‐A‐T‐T‐T‐T‐G‐A) by the diester method is described. The condensations were performed using dinucleotide blocks carrying suitable protecting groups. The intermediary products were d(G‐A), d(G‐A‐T‐T) and d(G‐A‐T‐T‐T‐T). These intermediates and the final product were characterized by UV. spectroscopy, high pressure liquid chromatography (HPLC.) and enzymatic degradation. The cleavage products were separated and analyzed by paper chromatography or HPLC. with an anion exchange column. They yielded the corresponding nucleosides and nucleotides in the correct ratios.
Nucleoside und Nucleotide. Teil 16. Verhalten von 1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyrimidinon‐5′‐triphosphat, 1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)pyridinon‐5′‐triphosphat und 4‐Amino‐1‐(2′‐Desoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinon‐5′‐triphosphat gegenüber DNA‐Polymerase
Authors: Wachtl Michael , Kohler Peter , Tamm Christoph 
Published: December 2004

Nucleosides and Nucleotides. Part 16. The Behaviour of 1‐(2′‐Deoxy‐β‐D‐ribofuranosyl)‐2(1H)‐pyrimidinone‐5′‐triphosphate, 1‐(2′‐Deoxy‐β‐D‐ribofuranosyl‐2(1H))‐pyridinone‐5′‐triphosphate and 4‐Amino‐1‐(2′‐desoxy‐β‐D‐ribofuranosyl)‐2(1H)‐pyridinone‐5′‐triphosphate towards DNA PolymeraseThe behaviour of nucleotide base analogs in the DNA synthesis in vitro was studied. The investigated nucleoside‐5′‐triphosphates 1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyrimidinone‐5′‐triphosphate (pppMd), 1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinone‐5′‐triphosphate (pppIId) and 4‐amino‐1‐(2′‐deoxy‐β‐D‐ribofuranosyl)‐2(1 H)‐pyridinone‐5′‐triphosphate (pppZd) can be considered to be analogs of 2′‐deoxy‐cytidine‐5′‐triphosphate. However, their ability to undergo base pairing to the complementary guanine is decreased. When pppMd, pppIId or pppZd are substituted for pppCd in the enzymatic synthesis of DNA by DNA polymerase no incorporation of these analogs is observed. They exhibit only a weak inhibition of the DNA synthesis. The mode of the inhibition is uncompetitive which shows that these nucleotide analogs cannot serve as substrates for the DNA polymerase.
Über Pterinchemie 76. Mitteilung [1] Eine einfache Synthese von Leucovorin
Authors: Khalifa Esam , Ganguly Abhoy N. , Bieri Jost H. , Viscontini Max 
Published: December 2004

A Convenient Synthesis of LeucovorinThe synthesis of leucovorin, a 5‐formyl‐(6R or S)‐5,6,7,8‐tetrahydropteroyl‐L‐glutamic acid (II) is described. The L‐folic acid was first reduced to (6R, S)‐tetrahy‐dro‐L‐folic acid (I); formylation with methyl‐formate in DMSO gave directly leucovorin (as a diastereomeric mixture) in good yields. To demonstrate, that the formylation occurred regiospecifically at N (5) and not at N (10), N (10)‐nitroso‐(6 R, S)‐tetrahydro‐L‐folic acid was formylated under the same conditions. Reductive elimination of the N (10)‐nitrosogroup gave the identical leucovorin as in the previous case. The synthetic leucovorin was biologically as active as the natural product with Streptococcus faecalis ATCC 8043 and Pediococcus cerevisiae ATCC 8081.
3‐Azawurtzitan und 3(4 → 5)abeo‐3‐Azawurtzitan
Authors: Klaus Rolf Otto , Ganter Camille 
Published: December 2004

3‐Azawurtzitane and 3(4 → 5)abeo‐3‐Azawurtzitane3‐Azawurtzitane (14) and 3(4 → 5)abeo‐3‐azawurtzitane (15) as well as derivatives thereof are described. The known tricyclic unsaturated ketone 1 was transformed to the properly functionalized endo‐amines 3, 5 and 12. Entry to the azawurtzitane system and its corresponding abeo‐compounds was achieved by three different cyclization procedures: aminomercuration with mercuric acetate in water (3 → 14, 5 → 16), olefin amination with mercuric acetate in dimethyl sulfoxide (3 → 18, 5 → 20 + 21) and intramolecular attack at an epoxide (12 → 24 + 25). Molecular rearrangements of 3‐azawurtzitanes to 3(4 → 5)abeo‐3‐azawurtzitanes and vice versa are described involving neighbouring group participation of the N (3) atom.
Synthesen und chemische Eigenschaften neuer «Donor‐Akzeptor»‐stabilisierter Molekülsysteme mit zentraler Bicyclo [4.4.1]undeca‐l (10), 3,6,8‐tetraen‐2,5‐diyliden‐Gruppe
Authors: Neidlein Richard , Zeiner Hartmut 
Published: December 2004

Syntheses and Chemical Properties of New ‘Donor‐Acceptor’‐stahilized Molecular Systems with a Central Bicyclo[4.4.1] undeca‐l(10).3,6,8‐tetraene‐2,5‐diylidenc GroupThe synthesis of X‐methyl‐2‐(5‐oxobicyclo[4.4.1]undeca‐l)10(,3,6,8‐tetraen‐2‐yliden)‐l,3‐benzodithiol (4) is described starting with the keto‐enol mixture 2 and 5‐methyl‐1,3‐benzodithiolium perchlorate. Under rearomatization of the central frame protonation of 4 yields the salt 4c. The reaction of 4 with dicyanoketene gives the ‘push‐pull‐substituted’ 5, and with 9‐carbonylfluorene the fulvalene derivative 7, which can be protonated by CF3CO2H at C(9″) to the salt 8. The reaction of 2‐methylthio‐l,3‐dithiolium jodide 9 with the keto‐enol mixture 2 yields 10, which, on protonation at the carbonyl group by CF3CO2H, gives the salt 11 under rearomatization. The spectral data of the new compounds 4, 4c, 5, 7, 8, 10 and 11 are reported and discussed.
The Synthesis of Dibenzyl trans‐{7‐oxo‐3‐phenyl‐6‐phenylacetamido‐1‐azabicyclo [3.2.0]heptane}‐2,2‐dicarboxylate (Carbapenam)
Authors: Hakimelahi Gholam Hosein , Ugolini Antonio , Just George 
Published: December 2004

AbstractThe synthesis of the title compound is described.
132. The Synthesis of Highly Strained Monocyclic and Bicyclic β‐Lactams (Δ1‐Carbapenem)
Authors: Hakimelahi Gholam Hosein 
Published: December 2004

AbstractThe synthesis of some β‐lactams and one Δ1‐carbapenem is described. The electronic activation of monocyclic β‐lactams of type 1 is not sufficient to generate a bioactive compound.
Sigmatropic Rearrangements Accompanying the Addition of Dichlorocarbene to Norbornadiene
Authors: Jefford Charles W. , Bernardinelli Gérald , Rossier Jean‐Claude , Zuber Jacques A. 
Published: December 2004

AbstractA new product arising from the reaction of dichlorocarbene with norbornadiene, 6endo‐(2,2‐dichlorovinyl)‐cis‐bicyclo[3.1.0]hex‐2‐ene, is described. It does not arise from the normal exo‐l,2‐adduct, but possibly originates by sigmatropic rearrangement of an initially formed zwitterionic intermediate.
Der [M+11]+‐Pik in den Massenspektren von Diaminen 38. Mitteilung über massenspektrometrische Untersuchungen
Authors: Kühne Hardy , Hesse Manfred 
Published: December 2004

The [M+ U]+‐Peak in the Mass Spectra of DiaminesThe mass spectra of di‐ and polyamines containing a 1,2‐ethandiamine or a 1,3‐propandiamine unit are quite often characterized by [M+ 1l]+‐peaks. It is demonstrated that these peaks correspond to a fragment‐ion formed by loss of H. from a formaldehyde‐condensation product (e. g. 15) or by loss of CH3. from a acetaldehyde‐condensation product (e. g. 16) with the diamine. The aldehydes are usually impurities in solvents (especially methanol) used by chromatography, synthesis etc. of the diamines.