bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bausteine von Oligosacchariden, XC. Synthese von Strukturen der inneren Core‐Region von Lipopolysacchariden
Authors: Paulsen Hans , Heitmann Axel C. 
Published: July 2007

Abstract2‐O‐Acetyl‐3,4,6,7‐tetra‐O‐benzyl‐L‐glycero‐α‐D‐manno‐heptopyranosylchlorid (6) läßt sich mit dem KDO‐Glycosylakzeptor 14 stereoselektiv zu dem α(1→5)‐glycosidisch verknüpften Disaccharid 24 umsetzen, dessen Entblockierung zu L‐α‐D‐Hepp‐(1→5)‐β‐KDOp‐OMe (30) führt. Die Umsetzung von 6 mit 22 führt stereoselektiv zum α(1→3)‐glycosidisch verknüpften Heptosedisaccharid 31, die von 6 mit 35 zum α(1→7)‐glycosidisch verknüpften Heptosedisaccharid 36. Die Entblockierung von 31 führt zu L‐α‐D‐Hepp‐(1→3)‐LD‐Hepp (34), die von 36 zu L‐α‐D‐Hepp‐(1→7)‐LD‐Hepp (39).
Notizen/Notes Formation of Trisubstituted 1,2,4‐Triazoles in the Cyclodehydration of 2‐Hydrazinothiazoles: Competition of Two Reaction Routes
Authors: Veverka Miroslav , Svêtlík Jan 
Published: July 2007

AbstractThe intramolecular cyclodehydration of ethyl (2‐hydrazinothiazol‐4‐yl)acetates 1a – f has been re‐examined. The reactions yield the desired thiazolo[2,3‐c]‐s‐triazoles 2a – f together with the unexpected trisubstituted 1,2,4‐triazoles 3a – f.
Synthese und Aggregationsverhalten chiraler Cystein‐Amphiphile mit s‐Triazin als verknüpfende Partialstruktur
Authors: Staatz Irina , Granzer Ulrich H. , Roth Hermann J. , Blume Alfred 
Published: July 2007

AbstractEs werden homologe Liposomenbausteine 3 mit L‐Cystein als chirale hydrophile Kopfgruppe synthetisiert. Als Verknüpfungseinheit zwischen Cystein und den lipophilen Alkylketten dient s‐Triazin. Mittels DSC‐ und Fluoreszenz‐Anisotropie‐Messungen lassen sich die Phasenübergangstemperaturen der Lipide bestimmen. Es kann gezeigt werden, daß eine den Phospholipiden analoge Relation zwischen Art und Länge der Ketten und der Phasenübergangstemperatur besteht. Einschlußversuche mit ionischen wasserlöslichen Farbstoffen ergeben Hinweise auf eine Interaktion der in Phosphatpuffer (pH = 7.0), gebildeten Vesikel mit kationischen, nicht jedoch mit anionischen hydrophilen Substanzen.
Zur Regiochemie von [4 + 2]‐Cycloadditionen mit Methylpyrano[3,4‐b]indol‐3‐onen und unsymmetrischen Dienophilen
Authors: Pindur Ulf , Erfanian‐Abdoust Houshang 
Published: July 2007

AbstractDie methylierten Pyrano[3,4‐b]indol‐3‐one 1a, 1b reagieren mit acyclischen, unsymmetrischen CC‐Dienophilen nach einer Diels‐Alder‐Reaktion/CO2‐Extrusion zu selektiv funktionalisierten Carbazolen 2. In Abhängigkeit von der Struktur der Reaktionspartner wird keine oder geringe bis hohe Regioselektivität festgestellt. Diethylmesoxalat reagiert mit 1a, 1b regioselektiv zu neuen 2,3‐difunktionalisierten Indolen 4a, 4b, die aus einer regiokontrollierten [4 + 2]‐Cycloaddition und Cycloreversion resultieren, wobei Pyrano[3,4‐b]indoldicarbonsäure‐diethylester 3a, 3b als Intermediate auftreten dürften.
Steroids, XLI. Neighbouring Group Participation, X. Neighbouring Group Participation and Fragmentation During the Solvolysis of the Epimers of 3‐Methoxy‐16‐(tolylsulfonyloxymethyl)‐estra‐1,3,5(10)‐trien‐17‐ol
Authors: Schneider Gyula , Hackler LÁSzló , Wölfling János , Bottka SÁNdor , Sohár PÁL 
Published: July 2007

AbstractThe four possible isomers of 16‐hydroxymethyl‐3‐methoxyestra‐1,3,5(10)‐trien‐17‐ol were converted into the 16‐tolylsulfonyloxymethyl‐17‐acetoxy esters 1b, 3b, 4b, 7b and into the 16‐tolylsulfonyloxymethyl‐17‐tetrahydropyranyl acetals 1c, 3c, 4c, 7c. On alkaline methanolysis of 1b and 7b, the α and β oxetanes 2 and 8 condensed to the D ring in the sterane skeleton were formed, while 3b and 4b yielded the fragmented product 5. Under similar experimental conditions, the acetals 1c, 3c, 4c, 7c were transformed into the 16‐methoxymethyl derivatives 1d, 3d, 4d, 7d.
Eine einfache Synthese von N‐Methyl‐L‐histidin
Authors: Barlos Kleomenis , Hondrelis John , Matsoukas John , Sanida Charicha , Lonergan Greg 
Published: July 2007

A Simple Preparation of N‐Methyl‐L‐histidineN‐Methyl‐L‐histidine is efficiently prepared in two steps starting from Nα‐trityl‐l‐histidine.
Selenonium‐Salze und Selenonium‐ylide von Cyclopentadien, Pentafulvenen, Indol und Pyrrol
Authors: Hartke Klaus , Wendebourg Hans Henning 
Published: July 2007

AbstractSelenoxide bilden mit Trimethylsilylcyclopentadien (1) die Selenoniocyclopentadienide 3 und 4. Selenoxide und Trifluoracetanhydrid reagieren mit Pentafulvenen zu den Mono‐ und Diselenonium‐Salzen 8 und 6, mit Indol zu dem 3‐Selenonium‐Salz 10 und mit Pyrrol zu den 2‐ und 3‐Selenonium‐Salzen 16 und 17. Die 2‐Isomere lagern mit Trifluoressigsäure quantitativ in die 3‐Isomere um. Deprotonierung von 16 und 17 führt zu den 2‐und 3‐Selenoniopyrroliden 26 und 27.
Crystal Structure and NMR Spectrometric Analysis of Palmarin
Authors: Yonemitsu Michiko , Fukuda Naomichi , Kimura Takeatsu , Komori Tetsuya , Lindner Hans Jörg , Habermehl Gerhard 
Published: July 2007

AbstractThe crystal structure of palmarin (1) has been determined by X‐ray diffraction. The ring C conformation was confirmed to be that of a half chair, and the same result was obtained from 1H‐NMR spectrometry. The ring C of chasmanthin (2) and glucosides of 1 and 2 (palmatoside A, and B) was also decided as a half boat by analysis of the 1H‐NMR spectra.
Synthese von O‐Glycopeptid‐Sequenzen des N‐Terminus von Interleukin‐2
Authors: Paulsen Hans , Adermann Knut 
Published: July 2007

AbstractEs wird eine Serie von O‐Glycopeptiden mit unterschiedlicher Kettenlänge von 3–10 Aminosäuren synthetisiert, die Struktur‐elemente des N‐Terminus von Interleukin‐2 darstellen. Schlüsselbaustein der Synthesen ist O‐(2‐Acetamido‐3,4,6‐tri‐O‐acetyl‐2‐desoxy‐α‐D‐galactopyranosyl)‐N‐(9‐fluorenylmethoxycarbonyl)‐L‐threonin‐tert‐butylester (9b), der sowohl C‐ wie auch N‐terminal verlängert werden kann. Mit 9b liegt ein Baustein vor, der das Einfügen von glycosylierten Hydroxyaminosäuren mit der bei Peptidsynthesen bewährten Schutzgruppenkombination Fmoc/tBu in Peptidketten erlaubt. Bei dem Aufbau der Ketten wird von Blocksynthesen Gebrauch gemacht. Die Substrate eignen sich zur Überprüfung der Strukturspezifität von Glycosyltransferasen.
Reactions of Organic Anions, 163 Reactions of Nitrobenzophenones with Carbanions Containing Leaving Groups. Vicarious Nucleophilic Substitution of Hydrogen versus Darzens or Wittig‐Horner Reactions
Authors: Ma̧kosza Mieczysłw , Baran Janusz , Dziewońska‐Baran Danuta , Goliński Jerzy 
Published: July 2007

AbstractCarbanions containing leaving groups at the carbanion center react with nitrobenzophenones by two general pathways: addition to the carbonyl group which results in the Darzens or Wittig‐Horner reaction and/or addition to the nitroaromatic ring resulting in the vicarious nuclephilic substitution of hydrogen. The former pathway dominates for p‐nitrobenzophenone, and the vicarious nuclephilic substitution is the major process for o‐nitro‐benzophenone; the extent of these two reactions for m‐nitrobenzophenone depends on the type of carbanion and the reaction conditions.
Umsetzung von Allyl(nonafluorbutyl)sulfonen mit Michael‐Akzeptoren, Synthese von Chrysanthemumsäurederivaten
Authors: Hanack Michael , Auchter Anneliese , Wunde Christian , Stoll Theodor 
Published: July 2007

Abstract(3‐Methyl‐2‐butenyl)nonafluorbutyl)sulfon (4) reagiert mit 3‐Methyl‐2‐butensäure‐ethylester (2) (Seneciosäure‐ethylester) unter Bildung von Chrysanthemumsäure‐ethylester (3). Als Nebenprodukt wird [5‐Methyl‐1‐(2‐methyl‐1‐propenyl)‐3‐pentenyl]‐[nonafluorbutyl)sulfon (5) erhalten. Das Nonaflon 4 ist durch Umsetzung von 3‐Methyl‐2‐butenylbromid (9) mit Natriumnonafluorbutansulfinat oder durch Umsetzung von Isopren mit Nonafluorbutansulfinsäure zugänglich. (3,3‐Dichlor‐2‐propenyl)(nonafluorbutyl)sulfon (12) reagiert mit Seneciosäure‐ethylester (2) nicht unter Bildung von Permethrinsäure‐ethylester (13), sondern unter Selbstkondensation zu dem Cyclopropylsulfon 15 und dem Disulfon 16.
Stereoisomere Aromastoffe, XXXI Tetrahydro‐2‐methylthiophen‐3‐ol ‐ Struktur und Eigenschaften der Stereoisomeren
Authors: Mosandl Armin , Hener Uwe , Fenske Heinz‐Dieter 
Published: July 2007

AbstractTetrahydro‐2‐methylthiophen‐3‐ol (6) wurde synthetisiert und flüssigkeitschromatographisch in cis‐ (6a/6a′) und trans‐Isomere (6b/6b′) getrennt. Durch Umsetzung mit (S)‐Tetrahydro‐5‐oxo‐2‐furancarbonsäurechlorid werden aus 6a/6a′ und 6b/6b′ die diastereomeren Ester 7–10 gebildet, deren flüssigkeitschromatographische Trennung und anschließende Hydrolyse zu den optisch reinen Stereoisomeren 6a, 6a′, 6b und 6b′ führt. Absolute Konfiguration und sensorische Bewertung der Stereoisomeren werden mitgeteilt.
Synthesis of Mono‐ and Sesquiterpenoids, XVI Synthesis of (‐)‐Pereniporins A and B, Sesquiterpene Antibiotics from a Basidiomycete
Authors: Mori Kenji , Takaishi Hideo 
Published: July 2007

AbstractStarting from (S)‐3‐hydroxy‐2,2‐dimethyl‐1‐cyclohexanone (5), the enantioselective total syntheses of (‐)‐pereniporins A (1) and B (2) were achieved in 33 steps (0.6% overall yield) and in 28 steps (1.8% overall yield), respectively.
Studies Relating to the Configuration and Conformation of 3,5‐Disubstituted Dihydro‐2(3H)‐furanones
Authors: Fischer János , Fodor Tamás , Dobay László , Kiss Béla , Tóth Gábor , Snatzke Günther , Ötvös László 
Published: July 2007

AbstractInternal prodrug analogues of enalapril were obtained by reduction of (1S)‐N‐[1‐(ethoxycarbonyl)‐3‐oxo‐3‐phenylpropyl]‐(S)‐alanyl‐(S)‐proline tert‐butyl ester (1) to the alcohols 2a and 2b followed by lactonization to (3S,5S)‐ and (3S,5R)‐N‐(tetrahydro‐2‐oxo‐5‐phenyl‐3‐furanyl)‐(S)‐alanyl‐(S)‐proline (4a and 4b), both isolated as the maleates. Their configuration and conformation have been elucidated by a combination of 1D‐ and 2D‐NMR techniques and with the help of CD measurements. In vitro inhibition of angiotensin‐converting enzyme (ACE) by 4a and 4b has been found to be similar to that of enalapril.
Synthese von Marchantin I, einem macrocyclischen Bis(bibenzylether) aus Riccardia multifida
Authors: Dienes Zoltán , Nógrádi Mihály , Vermes Borbála , Kajtár‐Peredy Mária 
Published: July 2007

Synthesis of Marchantin I, a Macrocyclic Bis(bibenzyl Ether) from Riccardia multifidaThe unambigous synthesis of marchantin (1), a bis(bibenzyl ether) with a 18‐membered ring, by Ullmann, Wittig, and modified Wurtz reaction is reported.
Nitriles in Heterocyclic Synthesis: A Novel Synthesis of 2‐Amino‐3‐pyrrolecarbonitriles
Authors: Hilmy Khalid Mohamed Hassan , Pedersen Erik B. 
Published: July 2007

Abstract2‐Amino‐3‐pyrrolecarbonitriles are prepared by the reaction of phenacylmalononitrile with primary aromatic amines using a catalytical amount of concd. HCl.
Enantioselective Microbial Reduction of 5‐Acetylisoxazolines – A Novel Method for Stereochemical Control on Yeast Reduction
Authors: Ticozzi Calimero , Zanarotti Antonio 
Published: July 2007

AbstractThe kinetics and the stereoselectivity of the reduction by baker′s yeast of racemic 5‐acetyl‐4,5‐dihydro‐3‐phenylisoxazole 1 to the corresponding alcohol in 2‐propanol/water mixtures are strongly dependent from the 2‐propanol/water ratio; at a ratio of 4.0, the reduction allows a kinetic resolution leading to alcohol 2 and ketone (R)‐1 Subsequent reduction of (R)‐1 with yeast in water and with Aspergillus niger leads to alcohols 3 and 4 with high ee.
1,4‐pentadien‐3‐ones, 31. 1‐(1‐cyclohexenyl)‐1‐propen‐2‐ones: Synthesis, properties, and stereoselective formation of 3‐aryl‐4‐(1‐cyclohexenylcarbonyl)perhydro‐1‐naphthalenones by sequential michael reaction
Authors: Richter Friedrich , Otto Hans‐Hartwig 
Published: July 2007

AbstractOn rearrangement, 1‐ethynyl‐1‐cyclohexanol (1) yields 1‐acetyl‐1‐cyclohexene (2). At −78°C in the presence of LDA, 2 reacts with aldehydes/ketones yielding the aldols 5/8, which are dehydrated to the title compounds 6 or 9. At room temp., a reaction between the lithium derivative of 2 and 6 ensues, yielding the bicyclic products 10. These can also be prepared independently from isolated 6 and 2 with LDA or butyllithium in high yields. The stereochemistry is elucidated by spectroscopic methods, and the minimum energy conformation of 10a is calculated. The stereoselective formation of 10 is explained by a lithium‐controlled sequential Michael reaction.
Synthese von (1α,7α,8β)‐(±)‐7‐Hydroxy‐1‐(hydroxymethyl)pyrrolizidin, der Necin‐Base rac‐Platynecin
Authors: Röder Erhard , Bourauel Thomas , Wiedenfeld Helmut 
Published: July 2007

Synthesis of (1α,7α,8β)‐(±)‐7‐Hydroxy‐1‐(hydroxymethyl)pyrrolizidin, the Necine rac‐Platynecinerac‐Platynecine (rac‐7) can easily be obtained in high yields from diethyl (±)‐cis‐2,3‐pyrrolidinedicarboxylate (rac‐1) by N‐alkylation to ethyl (±)‐cis‐2,3‐bis(ethoxycarbonyl)‐1‐pyrrolidinepropionate (rac‐2), Dieckmann reaction to ethyl (1α,8β)‐(±)‐6‐ethoxycarbonyl‐7‐oxo‐1‐pyrrolizidinecarboxylate (rac‐3), subsequent saponification, decarboxylation, reduction to (1α,7α,8β)‐(±)‐pyrrolizidine‐1,7‐carbolactone (rac‐6), and further reduction to the desired title compound rac‐7.
Chemie und Stereochemie der Iridoide, XIV. Aucubin und Scandosid aus Catalpol
Authors: Weinges Klaus , Ziegler Hans Jürgen 
Published: July 2007

Chemistry and Stereochemistry of Iridoids, XIV. — Aucubin and Scandoside from CatalpolAucubin (9), scandoside (10), and its methyl ester [“feretoside” (11)] were obtained, in good yields, from catalpol (1). The absolute configurations of 9–11 were established by correlation to catalpol, whose X‐ray crystal structure has previously been determined.
Synthese von L‐Prolin‐haltigen O‐Glycopeptiden
Authors: Paulsen Hans , Merz Gunnar , Brockhausen Inka 
Published: July 2007

Synthesis of L‐Proline‐Containing O‐GlycopeptidesThe synthesis of a number of L‐proline‐containing O‐glycopeptides in which 2‐acetamido‐2‐deoxy‐α‐D‐galacto‐pyranose is α‐glycosidically linked to L‐threonine is described. For N‐terminal extension with amino acids the building block 3 is preferred. For C‐terminal extension a new intermediate is developed, that includes the Aloc/tBu combination of protective groups which can be synthesized with high yield and stereoselectivity. The Aloc group shows a low steric hindrance and is very stable. Therefore, the carbohydrate‐containing compound 68 can also be coupled C‐terminally with low‐reactive L‐proline derivatives in good yields. The synthesized O‐glycopeptides shall be used in the investigation of the dependence of the protein structure on the glycosyltransferase activity of the biosyntheses of mucins.
Chemie und Stereochemie der Iridoide, XIII. Synthese von enantiomerenreinem (1R,2S,2″Z)‐(+)‐Methyljasmonat aus Catalpol
Authors: Weinges Klaus , Lernhardt Ulrich 
Published: July 2007

Chemistry and Stereochemistry of Iridoids, XIII. — Synthesis of Enantiomerically Pure Methyl (1R,2S,2″Z)‐(+)‐Jasmonate Starting from CatalpolEnantiomerically pure methyl (1R,2S,2″Z)‐(+)‐jasmonate (2), which was recognized as a component of the fragrance of the jasmine flower oil, was synthesized starting from catalpol (3). 2 is easily epimerized to 1. Thus, it is necessary to use very mild conditions in the course of the synthesis and purification. These results raise the question whether 2 exists as a natural product in the flower of jasmine and 1 arises during the isolation.
Synthesis and structure of some condensed quinazolines
Authors: Badawy Mohamed A. , Abdel‐Hady Sayed A. , Mahmoud Ahmed H. , Ibrahim Yehia A. 
Published: July 2007

AbstractCondensation of 2‐hydrazino‐4(3H)‐quinazolinone (1) with bielectrophilic reagents gives the corresponding triazoloquinazolines 8, the structures of which were established by selective synthesis through deamination of their N‐amino derivatives. The synthesis of methyl‐substituted derivatives of these angular tricyclic systems and their linear isomers was also achieved starting with 3‐methyl‐ and 1‐methyl‐2‐hydrazino‐quinazolinone.
Xylaral, ein Hydroxyphthalid‐Derivat aus Fruchtkörpern von Xylaria polymorpha (Ascomycetes)
Authors: Gunawan Sonny , Steffan Bert , Steglich Wolfgang 
Published: July 2007

Xylaral, a Hydroxyphthalide Derivative from Fruiting Bodies of Xylaria polymorpha (Ascomycetes)Fruiting bodies of Dead Man's Fingers, Xylaria polymorpha, contain a hydroxyphthalide derivative, xylaral (1), which exhibits a violet colour reaction with aqueous ammonia. 1 is a homologue of cyclopaldic acid (5) with a C14‐side chain containing an enone moiety.
Functionally substituted vinyl carbanions, 42. Synthesis of the top half of chlorothricolide
Authors: Hirsenkorn Rolf , Schmidt Richard R. 
Published: July 2007

Abstractβ‐Lithiated functionally substituted acrylates 2a–c prove to be versatile building blocks for spirotetronate syntheses useful in top half syntheses of the aglycon chlorothricolide 1 of the macrolide antibiotic chlorothricin. The electrophilic‐nucleophilic cyclohexanone derivatives 27‐cis/trans (with relative cis or trans relationship of the carboxylate group) required in this synthesis design are obtained via a cycloaddition route from pentenone in five steps. Generation of the dilithiated species from the acrylates 2a–c affords then the corresponding spirotetronates 32a–c, which serve as versatile intermediates in top half syntheses for different strategies in chlorothricolide total syntheses. Hydroxylation in the vinylic α‐position of the tetronate moiety and selective phenylselenylation provide the spirotetronates 39a‐cis/trans and 41a, which meet the requirements of a top half molecule. The same is true for a different strategy, which provides the aldehydes 42b‐cis/trans. The latter are then converted into the fully functionalized spirotetronates 44b‐cis/trans by treatment with vinylmagnesium bromide and subsequent hydroxylation at the vinylic α‐position. The investigations delineate similar convenient strategies for the syntheses of kijanolide and te‐tronolide, which are the aglycon portions of the structurally related macrolide antibiotics kijanimicin and tetrocarcin, respectively.
Heterocyclische β‐Enaminoester, 52. Neue Wege zu kondensierten Pyrimidinen über Iminophosphorane
Authors: Wamhoff Heinrich , Wintersohl Heinrich , Stölben Stephan , Paasch Joachim , Nai‐Jue Zhu , Fang Guo 
Published: July 2007

Heterocyclic β‐Enamino Esters, 52. — New Approaches to Condensed Pyrimidines via IminophosphoranesThe heterocyclic and carbocyclic 2‐(triphenylphosphoranyl‐ideneamino)‐3‐carboxylates 1a, b, 4a–d, and 8a, b, d react with isocyanates in a novel type of pyrimidine annulation to give heterocondensed 2‐alkoxy‐4‐pyrimidinones 3a–d, 5a–h, furthermore 14‐17 (revised constitutions) as well as 4(3H)‐quinazolinones 9a–g, 10a, b. The constitution of model compound 3a has been established by X‐ray analysis. — Crossover experiments reveal that partially saturated enamino esters, such as 1a, b, 4a–d, undergo strictly an intramolecular 1,3‐shift of the ester alkoxide; a mechanism accounting for this annulation reaction is discussed. Under these conditions, the anthranilates 8 afford a stabilized carbodiimide to which alcohols or amines add before condensation occurs to 4(3H)‐quinazolinones 9a–c, 10a, b; however, with the phenyl esters 8b, d the intramolecular 1,3‐migration of the phenoxide is clearly favoured to afford 9f,g. — Reaction of the iminophosphoranes 19a,b of the 1,4‐dihydropyridines 18a,b with acetylenedicarboxylates results in 1‐addition and Aza‐Wittig annulation to give the pyrido[1,2‐a]pyrimidines 21a–c.
EPC‐synthesis and fungistatic activity of a gloeosporone analog with an ω‐hydroxybutyl instead of the pentyl side chain on the macrocyclic ring
Authors: Seebach Dieter , Adam Geo , von dem Bussche‐Hünnefeld Christoph , Gisi Ulrich , Binder Heinz 
Published: July 2007

Abstract(+)‐5′‐Oxa‐gloeosporone (2), an analog of the natural germination self‐inhibitor (−)‐gloeosporone (1), is synthesized, largely following our previously published route to the parent compound. Thus, the hydroxybutyl side chain of 2 was introduced by hydroboration of a butenyl group (→ 14) which had been carried along throughout the synthesis up to the stage of the 14‐membered yne‐lactone 13. Silyl protection (→ 15), oxidation of the acetylene to a 1,2‐diketone moiety (→ 16), and deprotection with spontaneous intramolecular hemiacetal formation completed the synthesis of (+)‐2. The (+)‐oxa‐gloeosporone 2 exhibits an in vitro and in vivo antifungal activity spectrum with 14 microorganisms very similar to both the natural (1) and the unnatural enantiomer (ent‐1) of gloeosporone, indicating that neither the sense of chirality nor the side‐chain structure is important for the mode of action.
Synthese von 2‐(2‐Aminoethyl)thiophen über aktivierte Arylsulfonylaziridine
Authors: Fikentscher Rolf , Brückmann Raif , Betz Rainer 
Published: July 2007

Synthesis of 2‐(2‐Aminoethyl)thiophene via Activated ArylsulfonylaziridinesActivated arylsulfonylaziridines react with 2‐lithiothiophene under ring cleavage to afford sulfonamides 2, reductive cleavage of which with sodium bis(2‐methoxyethoxy)aluminium hydride yields 2‐(2‐aminoethyl)thiophene (3).
Reaktionen von Dinatrium‐dicyandithioacetat und Natrium‐dicyanthioacetamiden mit γ‐Bromcrotonsäure‐Derivaten
Authors: Wobig Dieter 
Published: July 2007

Reactions of Disodium Dicyanodithioacetate and Sodium Dicyanothioacetamides with Derivatives of γ‐Bromocrotonic AcidThe dicyanodithioacetate 3 reacts with the derivatives of γ‐bromocrotonic acid 4a and 4b to give the thieno‐[2,3‐b]thiophenes 5a and 5b. 3 can also be alkylated successively with two different alkylating reagents. In this way the compounds 5c, 6a, and 6b are prepared. Reactions of the dicyanothioacetamides 8a and 8b with 4a and 4b yield the thiazolidines 9a–d.
Ozonolyse von Olefinen, I. Ozonolyse von 1,4‐Cyclohexadien und säurekatalysierte Folgereaktionen von Primärspaltprodukten
Authors: Mittelbach Martin , Poklukar Norbert , Junek Hans 
Published: July 2007

Ozonolysis of Olefins, I. — Ozonolysis of 1,4‐Cyclohexadiene and Acid‐Catalysed Reaction of Primary Cleavage ProductsThe reaction of 1,4‐cyclohexadiene (1) with ozone under different reaction conditions was investigated. Complete ozonolysis of 1 in chloroform led to a highly explosive ozonide. Oxidative ozonolysis gave malonic acid in 30% yield, ozonolysis in alcoholic solutions of HCl gave alkyl 3,3‐dialkoxypropionates 3 in 60–70% yield and small amounts of the 1,1,3,3‐tetraalkoxypropane 4 as well as dialkyl malonate 5. Partial ozonolysis of 1 in HCl/methanol led to a mixture of 3, 5, and the corresponding (Z)‐3‐hexene derivatives 6a–c. Depending on the reaction time and concentration of HCl, also the two methanol addition products 7b and 7d could be obtained. To verify the structure of these two compounds, 4‐methoxycyclohexene (8) was ozonized in HCl/methanol, which gave a mixture of 7a–d.
Synthese von Undecose‐Derivaten als D‐Galactose‐Analoga zur spezifischen Modifikation Galactose‐bindender Proteine
Authors: Lehmann Jochen , Scheuring Markus 
Published: July 2007

Syntheses of Undecose Derivatives as D‐Galactose Analogues for Specific Modification of Galactose‐Binding ProteinsA series of undec‐ and dodecoses containing functional groups was obtained from 1,2:3,4‐di‐O‐isopropylidene‐α‐D‐galacto‐hexodialdo‐pyranose‐(1,5) (1) using Wittig and Grignard reactions to bring about chain elongation. The compounds resemble 6‐C‐alkylated D‐galactose derivatives which should have affinity to some galactose‐binding proteins. One potential photoaffinity reagent, 8‐azi‐6,7,8,9,10‐pentadeoxy‐D‐galacto‐undecose (12), was prepared from 6,7,9,10‐tetradeoxy‐1,2:3,4‐isopropylidene‐α‐D‐galacto‐8‐undecosulopyranose‐(1,5) (10). Compound 11 is suitable for syntheses of “spacer‐modified” oligosaccharides.
Reactions of organic anions, 164. Formation of gem‐dichlorocyclopropanes from perhalomethanes and alkenes in a phase‐transfer catalytic (PTC) system
Authors: Fedoryński Michał , Dziklińska Anna , Jończyk Andrzej 
Published: July 2007

AbstractPerhalomethanes YCCl3 (Y = Cl, Br) react with alkenes in the phase‐transfer catalytic system to give gem‐dichlorocyclopropanes.