bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthese von (trifluormethyl)substituierten Pyrethroiden
Authors: Nägele Ulli M. , Hanack Michael 
Published: July 2007

Abstract1,1,1‐Trifluoraceton (2) reagiert mit den Phosphoryliden 1 zu den (trifluormethyl)substituierten Olefinen 3a–d, wobei überwiegend die E‐Isomeren entstehen. 3‐(Trifluormethyl)‐2‐butennitril (3a) wird mit (Ethoxycarbonylmethylen)dimethylsulfuran (4a) zu 3‐Cyan‐2‐methyl‐2‐(trifluormethyl)cyclopropancarbonsäure‐ethylester (5a) umgesetzt, wobei vier Diastereomere entstehen. 5a läßt sich mit Tri‐n‐hexylsilan zum 3‐Formyl‐2‐methyl‐2‐(trifluormethyl)cyclopropancarbonsäure‐ethylester (Trifluorcaronaldehydsäure‐ethylester) (6) reduzieren. Aus dem Aldehyd 6 werden die mono(trifluormethyl)substituierten Pyrethroidester 7a, 7b und 7c gewonnen. 7a wird in das Pyrethroid 7f übergeführt.
Marine Bakterien, I. Synthese von Pentabrompseudilin, einem cytotoxischen Phenylpyrrol aus Alteromonas luteo‐violaceus
Authors: Laatsch Hartmut , Pudleiner Heinz 
Published: July 2007

AbstractEine neue Synthese für 2,3,4‐Tribrom‐5‐(3,5‐dibrom‐2‐hydroxyphenyl)pyrrol (1a, Pentabrompseudilin), einem antibakteriell, enzyminhibitorisch und cytotoxisch wirksamen Inhaltsstoff aus dem marinen Bakterium Alteromonas luteo‐violaceus, wird beschrieben. Für die Untersuchung von Struktur‐Wirkungs‐Beziehungen werden zahlreiche weitere 2‐Phenylpyrrole in einer Reaktionsfolge hergestellt, deren Schlüsselschritte die Grignard‐Reaktion von 2‐(1,3‐Dioxan‐2‐yl)ethylmagnesiumbromid (9d) mit Benzoylchloriden zu γ‐Phenyl‐γ‐ketoaldehyden 24 und deren Paal‐Knorr‐Cyclisierung sind.
Stereoselective Synthesis of Alcohols, XXXII. Synthesis of the Prelog‐Djerassi Aldehyde and of a C‐1/C‐9 Segment of 6‐Deoxyerythronolide
Authors: Hoffmann Reinhard W. , Ladner Wolfgang , Ditrich Klaus 
Published: July 2007

AbstractStereoselective (>95%) chain extension of the Masamune aldehyde 1 to the lactone 9 was achieved using the chiral pentenylboronate 8 as reagent. The lactone 9 was converted into the Prelog‐Djerassi aldehyde 2. Its subsequent reaction with the chiral pentenylboronate 8 resulted in the desired lactone 19. This reaction was, however, complicated by partial epimerisation of the aldehyde 2.
Radical Additions in Aqueous Medium: Direct Synthesis of 5‐Allyl‐Substituted γ‐Lactones from Allylic Bromides/Zinc and Methyl γ‐Oxocarboxylates
Authors: Kunz Thomas , Reißig Hans‐Ulrich 
Published: July 2007

AbstractFollowing a procedure published by Luche, 5‐allyl‐substituted γ‐lactones 2a–2d are prepared in good yield from methyl γ‐oxocarboxylates 1a–1c and allyl bromides/zinc dust in aqueous medium. The diastereoselectivity of this allylation reaction is compared to that of Lewis acid promoted additions of allyltrimethylsilane to chiral aldehydes.
Conformation of Antamanide
Authors: Kessler Horst , Bats Jan Willem , Lautz Jörg , Müller Arndt 
Published: July 2007

AbstractThe conformation of the cyclic decapeptide antamanide (1) in CDCl3 solution was determined by means of NMR‐spectroscopic methods. Distances obtained from 40 negative NOE values at 500 MHz at low temperature were used as constraints in calculations with the GROMOS molecular dynamics program package to elucidate the most stable backbone conformation in solution. It turned out that there is a fast conformational equilibrium between up to four conformations which differ in a flip about φ and ψ around the two amide bonds Ala4–Phe5 and Phe9–Phe10. Side chain conformations were determined using homo‐ and heteronuclear coupling constants. Carbon relaxation times provide information about the internal flexibility of 1. Three new antamanide derivatives in which Pro3, Pro7, or Pro8 have been substituted by γ‐thiaproline (Thz) were synthesized and crystallized from acetone/water. The X‐ray analyses of these Thz derivatives demonstrate that in the presence of water antamanide adopts a preferred structure which includes four water molecules for building up a compact hydrogen‐bonded structure, which differs from the conformation in chloroform sulution.
Zur Synthese und Dimroth‐Umlagerung von 4‐(Dialkylamino)‐2H‐1,3,5‐oxadiazin‐2‐thionen
Authors: Spitzner Roland , Andersch Jörg , Schroth Werner 
Published: July 2007

Concerning the Synthesis and the Dimroth Rearrangement of 4‐(Dialkylamino)‐2H‐1,3,5‐oxadiazine‐2‐thionesThe title compounds 3 are readily obtained by reaction of N,N‐dialkylchloroformamidines 2 with potassium thiocyanate. The amidines 2 can be prepared profitably from isocyanide dichlorides 1 with the aid of N‐(trimethylsilyl)dialkylamines. The thiones 3 behave very sensitively towards acids and are rearranged completely to 4‐(dialkylamino)‐2H‐1,3,5‐thiadiazin‐2‐ones 4 by treatment with acetic acid.
Synthesis of (‐)‐Biopterin
Authors: Mori Kenji , Kikuchi Haruhiko 
Published: July 2007

AbstractThe synthesis of (‐)‐biopterin (1) was accomplished by employing (1S,2S)‐1‐(2‐furyl)‐2‐(trityloxy)‐1‐propanol (6), derived from ethyl (S)‐lactate, as building block for the side chain.
Eigenschaften und Reaktionen substituierter 1,2‐Thiazetidin‐1,1‐dioxide: 2‐und/oder 4‐silylierte 1,2‐Thiazetidin‐1,1‐dioxide
Authors: Müller Martin , Meyle Eberhard , Otto Hans‐Hartwig , Paulus Erich F. , Plagge Herbert 
Published: July 2007

AbstractDurch Silylierung unter verschiedenen Bedingungen und in Abhängigkeit von den molaren Verhältnissen der Reaktanden können aus 1,2‐Thiazetidin‐1,1‐dioxid (β‐Sultam, 1) alle denkbaren an N‐ und C‐4 silylierten Produkte 2–11 erhalten werden. Die 2,3‐disubstituierten β‐Sultame 16 und 19 werden an C‐4 silyliert, wobei Disilylierung bevorzugt ist. Von 2d wird die Struktur durch eine Röntgenstrukturuntersuchung bei −130°C geklärt. Die Stabilität und einige spektroskopische Eigenschaften werden diskutiert.
Carboxy‐ and Cyano‐Hydroxylation of Alkenes. Synthesis of 3‐Hydroxy‐4‐amino Acids and Butyrolactones via the Isoxazoline Route
Authors: Halling Karen , Thomsen Ib , Torssell Kurt B. G. 
Published: July 2007

AbstractDichloro‐ and dibromoformaldoximes are useful 1,3‐dipolar cycloaddition reagents. They are conveniently preparated in situ, in high yields by dihalogenation of glyoxalic acid aldoxime with N‐bromo‐ and N‐chlorosuccinimide or tert‐butyl hypochlorite. Dehydrohalogenation with potassium hydrogen carbonate in the presence of alkenes gives 3‐halo‐isoxazolines in a one‐pot reaction. Reduction with iron pentacarbonyl gives β‐hydroxynitriles. Methoxylation and catalytic reduction give β‐hydroxy esters. Allyl alcohols and allylamines are transformed with halonitrile oxides into butyrolactones (DL‐angelica lactone) and DL‐3‐hydroxy‐4‐amino acids (carnitine, 4‐amino‐3‐hydroxybutyric acid), respectively. The lactonization is best effected by heating the γ‐silyloxy ester in acetic acid with potassium hydrogen sulfate as catalyst. A synthesis of N‐Boc‐dihydromuscimol is described.
Neuartige Umlagerungen in der Pregnanseitenkette
Authors: Annen Klaus , Hofmeister Helmut , Laurent Henry , Hoyer Georg‐Alexander 
Published: July 2007

Abstract17‐Acetoxy‐21‐(acetylthio)‐4‐pregnen‐3,20‐dion (3) reagiert mit einem großen Überschuß an Natriumazid in Methanol zu einem Gemisch der Umlagerungsprodukte Etiansäure‐methylester 11 und Spirodithiolanon 12. Der Reaktionsablauf wird in Abhängigkeit von Reaktionstemperatur und Lösungsmittel untersucht. Um weitere Einblicke in einen möglichen Umlagerungsmechanismus zu gewinnen, werden die Verbindungen 4–10, die 6α‐Methyl‐ und die D‐Homoverbindungen 13b und 13d als Modellsubstanzen synthetisiert und den Umlagerungsbedingungen unterworfen.
Strukturanalyse von Steroid‐17‐spiro‐dithiolanonen
Authors: Hoyer Georg‐Alexander , Annen Klaus , Cleve Gerhard , Herrmann Christoph , Hofmeister Helmut , Laurent Henry , Sheldrick William S. 
Published: July 2007

AbstractMit IR‐, CD‐, 1H‐NMR‐ und Massen‐Spektrometrie sowie Röntgenstrukturanalyse wurden die Strukturen von sieben Androstan‐17‐spiro‐3′‐(1′,2′‐dithiolan)‐4′‐onen bestimmt. Alle Verbindungen besitzen (17R)‐Konfiguration (17β‐CO, 17α‐S). Gleiche Stereochemie (17aR) kommt auch einer entsprechenden D‐Homoverbindung zu.
A Novel Example of a 7‐exo‐trig Heterocyclization
Authors: Martían Nazario , Quinteiro Margarita , Seoane Carlos , Soto José L. 
Published: July 2007

AbstractWe report that the open‐chain hydrazide 12, resulting from Knoevenagel condensation of cyanoacetohydrazide (10) with 3‐benzylidene‐2,4‐pentanedione (11), undergoes a 7‐exo‐trig heterocyclization, leading to the 1,3‐diazepinone 14.
Total Synthesis of [3aS‐(3aα,9aα,9bβ)]‐3a,4,5,9,9a,9b‐Hexahydro‐3a,6‐dimethyl‐1H‐benz[e]indene‐3,7(2H,8H)‐dione and Derivatives, Building Blocks for the Synthesis of Glucocorticoids
Authors: Daniewski Andrzej Robert , Piotrowska Emilia , Wojciechowska Wanda 
Published: July 2007

AbstractThe 1H‐benz[e]indenes 17–21, building blocks for the synthesis of steroids, were synthesized by coupling the silyl enol ethers 5 or 6 with ethylene acetals 7,8 of α,β‐unsaturated ketones, followed by cyclization under basic or acidic conditions.
Die Konfiguration der 1,2‐Diketon‐hydrazon‐oxime
Authors: Gnichtel Horst , Töpper Bernhard 
Published: July 2007

AbstractDie Konfiguration der 1,2‐Diketon‐(Z)‐hydrazon‐(E)‐oxime 3a–c wurde durch Ringschluß mit Formaldehyd zu den 1,2,4‐Triazin‐4‐oxiden 5a–c und den tautomeren 4‐Hydroxy‐1,2,4‐triazinen 6a–c sowie durch Beckmann‐Reaktion zu 1,2,4‐Triazolen 8a–c bewiesen. Aus dem Benzil‐(Z)‐hydrazon‐(Z)‐oxim 4a wird ein 1,2,5,6‐Oxatriazepin‐Derivat 9a erhalten.
Naturstoffe aus Arzneipflanzen, XXV Isolierung und Strukturaufklärung neuer Inhaltsstoffe aus dem sodaalkalischen Extrakt von Picrorhiza kurrooa
Authors: Weinges Klaus , Schick Hartmut , Neuberger Karl , Ziegler Hans Jürgen , Lichtenthäler Jochen , Irngartinger Hermann 
Published: July 2007

AbstractAus dem sodaalkalischen Extrakt von Picrorhiza kurrooa wurden zehn Verbindungen als Acetate kristallin isoliert. Während das Pentaacetyl‐6′‐cinnamoylcatalpol, Hexaacetyl‐6‐vanilloylcatalpol und Hexaacetylcatalpol direkt mit authentischen Proben identifiziert werden konnten, wurden die Strukturen der Verbindungen 1–6 und 8 durch Röntgenstrukturanalyse bzw. spektroskopisch ermittelt. Die acetylierten Cucurbitacin‐glucoside 3–5 weisen gegenüber den natürlichen Cucurbitacinen eine verkürzte Seitenkette auf. Da sie im Neutralextrakt chromatographisch nicht nachgewiesen werden konnten, müssen 3–5 erst bei Extraktion bzw. Aufarbeitung entstehen und Artefakte darstellen. Als einziges acetyliertes C30‐Cucurbitacin‐glucosid konnte (20R)‐3β,16α,20,25‐Tetrahydroxy‐2β‐(β‐D‐tetraacetylglucopyranosyloxy)‐10α‐cucurbit‐5‐en‐22‐on (8a) kristallin erhalten werden.
Reaction of Some Cyclic Dienamines of Carbothioic Acid Anilides with Malononitrile
Authors: Bogdanowicz‐Szwed Krystyna , Rys Barbara 
Published: July 2007

AbstractMorpholino enamines 1,2, and 3 of 2‐(cyclopentylidene)‐1‐cyclopentanone, 2‐(1‐cyclohexenyl)‐1‐cyclohexanone, and 2‐(cycloheptylidene)‐1‐cycloheptanone, respectively, react with aryl isothiocyanates to yield 1‐cycloalkene‐1‐carbothioic acid anilides 4, 5, and 6, respectively. Compounds 4 and 5 react with malononitrile to give the hexahydroisoquinolines 9 and the cyclopenta[c]pyridine 11, respectively.
Facile Reductive Cleavage of Oximes with a Low‐Valent Titanium Reagent
Authors: Balicki Roman , Kaczmarek Lukasz , Malinowski Marek 
Published: July 2007

AbstractThe application of the TiCl4/SnCl2 reagent system in the reductive deoximation of various ketoximes and aldoximes under mild conditions is reported. The corresponding carbonyl compounds were formed in high yields.
Enantiomerically Pure Building Blocks from Sugars, 10 2,3‐Dihydropyranones with Contiguous Chiral Centers: Practical Routes for Their Aquisition and Evaluation of their Reaction Potential
Authors: Lichtenthaler Frieder W. , Nishiyama Shigeru , Weimer Thomas 
Published: July 2007

AbstractA practical, large‐scale adaptable four‐step procedure has been developed for the conversion of D‐glucose into pyranoid enediolone esters with (R,R)‐configuration in contiguous chiral centers, involving hydrolysis of the readily accessible bis‐acetonide of α‐D‐ribo‐hexos‐3‐ulose (12) and base‐mediated acylation. The sequence provides the acetyl (3), benzoyl (4) and pivaloyl (6) dihydropyranones in overall yields well exceeding 40%, whilst the maltose‐derived glucosyloxy‐substituted analogue 11 is accessible even more efficiently (69%) by low‐temperature benzoylation followed by DMSO/acetic anhydride treatment. – With the tribenzoate 4 as a model simply feasible addition reactions of preparative interest were evaluated, resulting in a unique transfer of chirality from one side of the pyranoid ring to the other upon treatment with methanol/K2CO3 (4 → 23), in C‐branching (4 → 18) or C‐extension (4 → 19), and in an unusual photoaddition of acetone to an O,O‐isopropylidene‐dihydropyrane (4 → 24). Particular attention is given to rationalization of the mechanisms underlying these additions and the regio‐ and diastereoselectivities attainable.
Epoxytetrahydroedulan, a New Terpenoid from the Hairpencils of Euploea (Lep.: Danainae) Butterflies
Authors: Francke Wittko , Schulz Stefan , Sinnwell Volker , König Wilfried A. , Roisin Yves 
Published: July 2007

AbstractThe main component among the volatiles from hairpencils of male danaid butterflies of the genus Euploea was found to be 9,10‐epoxytetrahydroedulan: (1R,2S,4S,7R, 10S)‐1,6,6,10‐tetramethyl‐3,11‐dioxatricyclo[5.4.0.02,4]undecane (12). Identification and synthesis of the compound are described. Another edulan derivative, (1R,3S,6R)‐1,3,7,7‐tetramethyl‐2‐oxabicyclo[4.4.0]dec‐9‐en‐8‐one (13) could be identified from the hairpencils of Danaus plexippus males.
Synthese von 1,4‐Di‐O‐acetyl‐2,3‐didesoxy‐α/β‐D‐pentofuranose und ‐pentopyranose
Authors: Diekmann Elke , Friedrich Klaus , Lehmann Jochen 
Published: July 2007

Synthesis of 1,4‐Di‐O‐acetyl‐2,3‐dideoxy‐α/β‐D‐pentofuranose and ‐pentopyranoseStarting from D‐mannitol, the diacetates 8 and 9 of 2,3‐dideoxy‐D‐pentofuranose and ‐pentopyranose are synthesized. The 1H‐NMR and 13C‐NMR spectra of the compounds are given.
Condensed Purines, I Synthesis of 6,7‐Dihydro‐1,3‐dimethylpyrimido[2,1‐f]purine‐2,4,8(1H,3H,9H)‐triones
Authors: Kalcheva Veneta , Stoyanova Diana , Simova Svetlana 
Published: July 2007

AbstractThe title compounds 2a–d and 4a–d are the sole products of the reaction between 8‐aminotheophylline (1) or 8‐(benzylamino)theophylline (3) and methyl acrylate, crotonate, methacrylate, and cinnamate in the presence of basic catalysts (Triton B or KOH). The structures of the compounds were determined by elemental analysis, spectral data, chemical transformations, and synthesis.
Studies with Alkylheteroaromatic π‐Deficient Compounds: Novel Synthesis of Thieno[3,4‐d]pyridazines and Phthalazines
Authors: Elnagdi Mohamed Hilmy , Negm Abdalla Mohamed , Erian Ayman Wahba 
Published: July 2007

AbstractEthyl 1‐aryl‐5‐cyano‐1,6‐dihydro‐4‐methyl‐6‐oxo‐3‐pyridazinecarboxylates 1 react with elemental sulphur in ethanolic basic solutions to yield thieno[3.4‐d]pyridazines 2. Compounds 2 readily react with electron‐deficient olefins to yield phthalazines.
Synthetic microbial chemistry, XXIII. Synthesis of optically active virginiae butanolides A, B, C, and D and other autoregulators from streptomycetes
Authors: Mori Kenji , Chiba Naoki 
Published: July 2007

AbstractOptically active A‐factor (1), the factor from Streptomyces viridochromogenes (2), the factors from S. bikiniensis and S. cyaneofuscatus (3–5), and virginiae butanolides A (6), B (7), C (8), and D (9) were synthesized starting from (S)‐(−)‐paraconic acid (10). The absolute configurations of virginiae butanolides A and C were deduced to be (2S,3R,1′R).
Constituents of holothuroidea, I. Isolation and structures of three triterpenoid aglycones, cucumechinol A, B, and C, from the sea cucumber Cucumaria echinata
Authors: Miyamoto Tomofumi , Togawa Kenichi , Higuchi Ryuichi , Komori Tetsuya 
Published: July 2007

AbstractThree new holostane2)‐type triterpenoid aglycones named cucumechinol A (1), B (2), and C (3) were isolated from the acidic hydrolysate of the crude glycoside mixture prepared from the whole sea cucumber Cucumaria echinata. The structures were identified on the basis of spectral evidence as 3β‐hydroxyholost‐9(11)‐ene‐16,23‐dione (1), 3β‐hydroxyholost‐9(11)‐en‐23‐one (2), and 3β‐hydroxyholost‐8(9)‐ene‐16,23‐dione (3), respectively.
Biologically active glycosides from asteroidea, XX. Glycosphingolipids from the starfish Asterina pectinifera,1. Isolation and characterization of acanthacerebroside B and structure elucidation of related, nearly homogeneous cerebrosides
Authors: Higuchi Ryuichi , Natori Takenori , Komori Tetsuya 
Published: July 2007

AbstractA ceramide monohexoside, acanthacerebroside B1b,2a), was purified from the water‐insoluble lipid fraction of the chloroform/methanol extract of the starfish Asterina pectinifera Müller et Troschel using reversed‐phase HPLC. A new method for identification of components of the ceramide by means of HPLC was developed. The separation and structure elucidation of related, nearly homogeneous cerebrosides which behaved as homogeneous compounds is also described.
Biologically active glycosides from asteroidea, XXI. Structure of pectinioside C: Determination of the stereochemistry of the C‐17 side chain of the steroidal aglycone
Authors: Honda Masanori , Igarashi Takashi , Komori Tetsuya 
Published: July 2007

AbstractThe 3,6‐di‐O‐acetyl derivative 3 of the desulfated aglycone of pectinioside C, (20S,24S)‐24‐ethylthoransterol A (2), and its 24R and 24RS stereoisomers 4 and 27 have been synthesized stereoselectively from the pregnane derivative 3,6‐di‐O‐acetyl‐asterone (5). Herewith, the stereochemistry at the C‐17 side chain of 2 and of pectinioside C (1) has been determined. (20S,24S)‐3β‐Acetoxy‐24‐ethyl‐20‐hydroxycholest‐5‐en‐23‐one (18), its 24R and 24RS stereoisomers 21 and 24, respectively, and some steroids with (20S)‐20‐hydroxy‐24ζ‐methyl‐26‐homo‐25ζ‐cholestane side chain have also been synthesized.
Desmethyl(trifluormethyl)actinomycine
Authors: Giencke Astrid , Lackner Helmut 
Published: July 2007

Demethyl(trifluoromethyl)actinomycinsThe synthesis of new 4‐(trifluoromethyl)benzoic acid derivatives 2–10 and their coupling with amino acids and peptides 12, 13, 15 is described. They serve as precursors for the synthesis of the hitherto unknown demethyl(trifluoromethyl)actinocin dimethyl esters 11, demethyl‐trifluoromethyl‐actino‐cinyl peptides 14, 16, 18 and the demethyl‐trifluoromethyl‐actinomycins 17. Although spacially comparable with the methyl residues, the 4‐ and 6‐trifluoromethyl groups have unexpected strong influences on the antibiotic and cytostatic properties of the actinomycins. The CH3/CF3 exchange makes it possible to bring NMR‐analytically useful hetero nuclei into the centre of the actinomycin/DNA complex (Figure 1).
Semisynthetische Myxovirescine: Austausch des α‐Hydroxycarbonsäure‐Segments und Modifikation der Ringgröße
Authors: Borgschulte Katrin , Trowitzsch‐Kienast Wolfram , Höfle Gerhard 
Published: July 2007

Semisynthetic Myxovirescins: Exchange of the α‐Hydroxycarboxylic Acid Segment and Modification of the Ring SizePartial degradation reactions of the macrocyclic lactam‐lacton antibiotic myxovirescin A1 (1) yield the key building blocks 2 and 26. From these myxovirescin analoga are reconstituted with various alkyl groups at position C‐2 with R and S configuration. Furthermore a ring‐contracted (24) and a ring‐enlarged (29) macrocycle are synthesized. The growth of E. coli is best inhibited by the natural myxovirescin A1 with a (2S) propyl substitution whilst 24 and 29 do not inhibit the growth of E. coli at all.
Hydrazinüberbrückte Annulene, 7. Synthese von 6H‐9b,9c‐Diazacyclopenta[cd]phenalen‐5,7‐dicarbonsäure‐diethylester
Authors: Flitsch Wilhelm , Lewinski Ulrike , Temme Robert , Wibbeling Birgit 
Published: July 2007

Hydrazino‐Bridged Annulenes, 7. — Synthesis of Diethyl 6H‐9b,9c‐Diazacyclopenta[cd]phenalene‐5,7‐dicarboxylateThe 1,4‐dihydropyridine 4 has been obtained from 1‐amino‐pyrrole and diethyl 2,6‐dioxo‐3,5‐heptanedicarboxylate. Subsequent Vilsmeier reaction led to the aldehyde 7 which could be transformed into the tricyclic aldehyde 8b in a repeated Vilsmeier reaction. Final cyclization was achieved with sodium ethanolate yielding the extremly unstable diazacyclo‐penta[cd]phenalene derivative 9.
Pyrrolo[1,2‐b]cinnolin‐6,8‐dicarbonsäure‐diethylester: Produkt einer anomalen Vilsmeier‐Reaktion
Authors: Flitsch Wilhelm , Lauterwein Jürgen , Leimkühler Manfred , Leaver Derek , Lewinski Ulrike , Mattes Rainer , Temme Robert , Wibbeling Birgit 
Published: July 2007

Diethyl Pyrrolo[1,2‐b]cinnoline‐6,8‐dicarboxylate, a Product of an Anomalous Vilsmeier ReactionA byproduct of the Vilsmeier reaction of 1 has been shown by X‐ray structure determination to be the pyrrolo[1,2‐b]cinnoline 3. Informations concerning the mechanism of formation of 3 have been obtained from labeling experiments and an unequivocal assignment of NMR spectra.
Synthesis of N,N′‐bis(phenylsulfonyl)‐1,2‐bis(4‐pyridyl)ethylenediamines
Authors: Braña Miguel F. , Castellano José M. , Yunta María J. R. 
Published: July 2007

AbstractReaction of (4‐pyridylmethyl)amine (3) with benzenesulfonyl chlorides 2a—i affords the corresponding N‐(4‐pyridylmethyl)benzenesulfonamides 4a—i which are converted into the N‐oxides 5 by treatment with hydrogen peroxide and acetic acid. Treatment of compounds 4 with their N‐oxides 5 in acetic anhydride results in dimerization to give the corresponding N,N′‐bis(phenylsulfonyl)‐1,2‐bis(4‐pyridyl)ethylenediamines 6a–d, f. The mixed ethylenediamines 6e, g are similarly synthesized from differently substituted sulfonamides and N‐oxides.
Reactions of 1‐acetyl‐3‐(dicyanomethylene)‐1,3‐dihydro‐2H‐indol‐2‐one with amines
Authors: Younes Mansour I. 
Published: July 2007

AbstractReaction of the title compound 1 with aliphatic, aromatic or heterocyclic amines leads to quinoline and indole derivatives 3 and 4, respectively.
Synthese enantiomerenreiner γ‐Keto‐δ‐aminosäuren, zentrale Bausteine vieler Enzyminhibitoren
Authors: Radunz Hans‐Eckart , Reißig Hans‐Ulrich , Schneider Günther , Riethmüller Angelika 
Published: July 2007

Synthesis of Enantiomerically Pure γ‐Keto‐δ‐amino Acids, Central Building Blocks of Enzyme InhibitorsAn enantioselective and efficient synthesis of γ‐keto‐δ‐amino acids as building blocks for certain enzyme inhibitors is presented. These compounds are also attractive for syntheses of homostatine derivatives.
Diels‐Alder reactions of 1‐phenylpyrano[3,4‐b]indol‐3‐ones with alkynes: New functionalized carbazoles
Authors: Pindur Ulf , Erfanian‐Abdoust Houshang 
Published: July 2007

Abstract3‐Indolylalkanoic acids 2 react with benzoic acid anhydride under catalysis of Et2O ‐ ZnCl2 and mild conditions to furnish the 1‐phenyl‐substituted pyrano[3,4‐b]indol‐3‐ones 1c, 1d, and 3a, 3b. Products 1c, 1d, and 3b may be converted into the novel functionalized carbazoles 4 and 5 by reaction with acceptor‐substituted alkynes.
Synthese neuer 8‐Azapurine
Authors: Ried Walter , Guryn Roman , Laoutidis Joannis 
Published: July 2007

Synthesis of New 8‐AzapurinesThe ethyl 5‐amino‐1H‐1,2,3‐triazole‐4‐carboxylates 1 react with orthoformate and hydrazine or substituted phenethylamine to yield the 8‐azapurines 3, 5, and 8, respectively.