bluuebunny/crossref_metadata_2025_split huggingface dataset:
Further Investigation of the Nature of the C‐Li Bond. Structures of a Phenylthiomethyllithium Complex and ofa Methylthiomethyllithium Complex
Authors: Amsturz René , Laube Thomas , Schweizer W. Bernd , Seebach Dieter , Dunitz Jack D. 
Published: December 2004

AbstractPhenylthiomethyllithium/N,N,N′,N′‐tetramethylethylenediamine (TMEDA) (1:1) is shown by X‐ray analysis to be dimeric in the crystalline state. The structural unit contains a six‐membered ring in which each Li is bonded to the terminal C atom of one thioanisole and to the S atom of the other, as well as to the two N atoms of a TMEDA. Methylthiomethyllithium/TMEDA (1:1) is also dimeric, but the structural unit contains a four‐membered ring in which each Li is bonded to two C atoms and to the two TMEDA N atoms. An error has been detected in an earlier published electron‐density difference map for 2‐lithio‐2‐phenyl‐1, 3‐dithiane/TMEDA/THF (1:1:1). The conclusion drawn then that this complex exists as a tight ion‐pair in the crystal is now retracted.
Synthese und 1H‐NMR‐Studie der vier unverzweigten peracetylierten β‐D‐Glucopyranosyl‐β‐gentiobiosen
Authors: Rychener Martin , Bigler Peter , Pfander Hanspeter 
Published: December 2004

Synthesis and 1H‐NMR Study of the Four Unbranched Peracetyl‐β‐D‐glucopyranosyl‐β‐gentiobiosesWith regard to the structure elucidation of an unknown trisaccharide isolated from the stigmas of garden crocusses (Crocus neapolitanus var.), the four unbranched (1→6)‐, (1→4)‐, (1→3)‐, and (1→3)‐, and (1→2)‐connected β‐D‐glucopyranosyl‐β‐gentiobiose peracetates were synthesized. A complete analysis of the 1H‐NMR spectra of the four trisaccharide peracetates was carried out.
Isolierung und Strukturaufklärung von Neapolitanose (O‐β‐D‐Glucopyranosyl‐(1→2)‐O‐[β‐D‐glucopyranosyl‐(1→6)]‐(D‐glucose), einem neuen Trisaccharid aus den Stempeln von Gartenkrokussen (Crocus neapolitanus var.)
Authors: Rychener Martin , Bigler Peter , Pfander Hanspeter 
Published: December 2004

Isolation and Structure Elucidation of Neapolitanose (O‐β‐D‐Glucopyranosyl‐(1→2)‐O‐[β‐D‐glucopyranosyl‐(1→6)]‐D‐glucose), New Trisaccharide from the Stigmas of Garden Crocusses (Crocus neapolitanus var.)From the stigmas of Crocus neapolitanus var. ‘Blue Bird’ two new crocetin glycosyl esters were isolated. They contained a hitherto unknown trisaccharide. For the structure elucidation a homonuclear 2D‐1H‐NMR‐shift‐correlation experiment was carried out with the peracetate of the isolated trisaccharide. This experiment revealed that the carbohydrate is O‐β‐D‐glucopyranosyl‐(1→2)‐O‐[β‐D‐glucopyranosyl‐(1→6))]‐D‐glucose, for which we suggest the name ‘neapolitanose’. The two new C20‐carotenoids from Crocus neapolitanus are crocetin (β‐gentiobiosyl) (β‐neapolitanosyl) ester (4) and crocetin di(β‐neapolitanosyl) ester (5).
Sambucinol and sambucoin, two new metabolites of Fusarium sambucinum possessing modified trichothecene structures. 41st Communication on verrucarins an roridins
Authors: Mohr Perer , Tamm Christoph , Zürcher Werner , Zehnder Margareta 
Published: December 2004

AbstractSambucinol (2) and sambucoin (4), two C15‐trichothecenes, have been isolated from cultures of Fusarium sambucinum. The structures were deduced from spectroscopic data and by X‐ray diffractoin. A hypothetical biogenetic pathway is proposed.
1,4‐Diazobicyclo[2.2.2]octane‐catalyzed coupling of aldehydes and activated double bonds. Part 3. A short ans practical synthesis of mikanecic acid (4‐vinyl‐1‐cyclohexene‐1,4‐dicarboxylic acid)
Authors: Hoffmann H. M. R. , Rabe Jürgen 
Published: December 2004

AbstractThe title dicarboxylic acid 1d has been prepared in 24% overall yield via, 1,4‐diazabicyclo[2.2.2]octane (DABCO)‐catalyzed coupling of ethanal and tert‐butyl propenoate (3) to 4, SN2′‐reaction to tert‐butyl (Z)‐2‐romomethyl‐2‐butenoate (5a), dehydrobrominatin to tert‐butyl 2‐methylidene‐3‐butenoate (2c), dimerizatoin to di‐tert‐butyl 4‐vinyl‐1‐cyclohexene‐1,4‐dicarboxylate (1c) and acidic ester cleavage. Acidic cleavage of easily obtainable 5a affords (Z)‐2‐bromomethyl‐2‐butenoic acid (5a) in 68% yield with respect to ethanal.
Intermolecular Electron Spin Transfer between Naphthalene π‐Systems Separated by a Variable Number of Spirobonded Cyclobutane Rings, An. ESR and ENDOR Study
Authors: Gerson Fabian , Huber Walter , Martin Wiliam B. , Caluwe Paul , Pepper Tim , Szwarc Michael 
Published: December 2004

AbstractThe radical anions of the compounds N1N, N3N and N5N, in which two naphthalen π‐systems are separated by 1, 3 and 5 spirobonded cyclobutane rings, respectively, and tha tof the reference compound N1, containing one naphthalene π‐system and one cyclobutane ring, have been studied by ESR and ENDOR spectroscopy under a variety of experimental conditions. The intramolecular electrons spin transfer between the two π‐moieties in N3N and N5N is slow on the hyperfine time‐scale, irrespective of the applied conditions. It is also slow in N1N, except for media of high solvating power. In such media, with a slight reduction of N1N to its radical anion, a paramagnetic species is observed, the hyperfine data for which are consistent with N1N to its radical anion, a paramagnetic species is observed, the hyperfine data of which are consistent with N1N, undergoing a fast intramolecular electron spin tansfer. The ESR and ENDOR spectra of this species are superimposed on those characteristic of a slow transfer. It is suggested that the fast and slow transfer involve the syn‐ and anti‐conformations, respectively, since the distance, r, between the two naphthalene π‐systems of N1N is considerably shorter in the former than in the latter (r = 740 vs. 880 Pm for the distance between the centres of the π‐systems). Glassy solutions of exhaustively reduced N1N display signals of the dianion triplet state, whereas no such signals are found for N3N and N5N. The zero‐field splitting parameter, D, is 4.7 mT, corresponding to r ≈ 480 pm.
Trennung und absolute Konfiguration der C(8)‐epimeren (all‐E)‐Neochrome (Trollichrome) und ‐Dinochrome
Authors: Märki‐Fischer Edith , Buchecker Richard , Eugster Conrad Hans 
Published: December 2004

Separation and Absolute Configuration of the C(8)‐Epimeric (app‐E)‐Neochromes (Trollichromes) and ‐DinochromesThe C(8′)‐epimers of (all‐E)‐neochrome were separated by HPLC and carefully characterized. The faster eluted isomer, m.p. 197.8–198.3°, is shown to have structure 3 ((3S,5R,6R,3′S,5′R,8′R)‐5′,8′‐epoxy‐6,7‐dodehydro‐5,6,5′,8′‐tetrahydro‐β,β‐carotene‐3,5,3′‐triol). To the other isomer, m.p. 195‐195.5°, we assign structure 6, ((3S,5R,6R,3′S,5′R,8′R)‐5′,8′‐epoxy‐6,7‐didehydro‐5,6,5′,8′‐tetrahydro‐β,β‐carotene‐3,5,3′‐triol). The already known epimeric dinochromes (= 3‐O‐acetylneochromes) can now be formulated as 4 and 5, (‘epimer 1’ and its trimethylsilyl ether) and 7 and 8, (‘epimer 2’ and its trimethylsilyl ether), respectively.
Enantioselective synthesis of (+)‐ and (−)‐cis‐2‐methyl‐4‐propyl‐1,3‐oxathiane and their olfactive properties
Authors: Pickenhagen Wihelm , Brönner‐Schindler Helene 
Published: December 2004

AbstractThe enantioselective synthesis of (+)‐ and (−)‐cis‐2‐methyl‐4‐propyl‐1,3‐oxathine 8 and 9 form (E)‐2‐hezen‐1‐ol (1) as common starting material is described. The two enantiomeric forms exhibit different organoleptic properties.
Synthesis of (−)‐Hobartine and Related Indole Alkaloids
Authors: Darbre Tamis , Nossbaumer Cornelius , Borschberg Hans‐Jürg 
Published: December 2004

AbstractAn improved method for obtaining optically pure (S)‐(l‐p‐menthen‐8‐yl)amine (12) has led to expedient syntheses of two hypothetical biogenetic intermediates on the way to aistoteline (7), namely (S)‐(N)‐(l‐p‐menthen‐8‐yl)‐2‐(3‐indolyl)ethylamine (3) and (S)‐(N)‐(l‐p‐menthen‐8‐yl)‐2‐(3‐indolyl)ethylideneamine (4). The latter has been transformed into (−)‐hobartine (6) in 64% yield via a stereoselective biomimetic cyclization by treatment with HCOOH. This unambiguous synthesis establishes the hitherto unknown absolute configuration of (−)‐hobartin (6). Several model cyclization reactions of N‐substituted α‐(terpen‐8‐yl)imine derivatives yielding unsaturated 3azabicyclo [3.3.1]nonane compounds are described.
Low‐Temperature 13C‐NMR Spectra of 6Li‐ and 13C‐Labelled Sulfur‐ and Selenium‐Substituted Organolithium Derivatives
Authors: Seebach Dieter , Gabriel Josef , Hässig Robert 
Published: December 2004

AbstractThe 13C‐NMR spectra of 19 different, singly, doubly, and triple 13C‐labelled α‐sulfur‐ and α‐selenium‐substituted 6Li‐derivatives generated from methyl and phenyl thioethers, thioacetals, trithio‐orthoesters and from their selenium analogues have been recorded in ethereal solutions (tetrahydrofuran (THF), 2‐methyltetrahydrofuran (MTHF) at temperatures between −30° and −110°. The effects of H/Li‐exchange upon chemical shifts and coupling constants, as well as the values and multiplicities of Li, 13C‐coupling are interpreted in vie wof crystal structures of some of the same compounds. In two thirds of the cases studied, the H‐decoupled 13C‐NMR signals observed below −80° were triplets, proving that the C‐atoms are bonded to single 6Li‐atoms. This is compatible either with monomeric or with dimeric, heteroatom‐bridged structures. The direct 1H, 13C‐ and 13C, 13C‐coupling constants (1J) decrease, the 13C, 77Se‐coupling constants increase upon lithiation. More striking is that the geminal coupling 13C‐S‐13C (2J) is too small to be observed in the non‐metalated species, while it ranges from 3.7 to 7.5 Hz in the lithiated derivatives. These observations may be interpreted as resulting from delocalization of electron density from the carbonionic center towards the adjacent heteroatom.
Kobalt‐katalysiert Cycloadditionen von Alkinen und Nitrilen zu Pyridinen: Ein neuer Zugang zu Pyridoxin (Vitamin B6)
Authors: Geiger Rudolf E. , Lalonde Michel , Stoller Hansijörg , Schleich Kuno 
Published: December 2004

Cobalt‐Catalyzed Cycloaddition of Alkynes and Nitriles to Pyridines: A New Route to Pyridoxine (Vitamin B6)A new synthesis of pyridoxine hydrochloride (1) based on a Co‐catalyzed cycloaddition of MeCN with substituted di(2‐propynyl) ethers (3 and 16) is described. The reaction sequences following cycloaddition and leading to 1 involve as key steps the rearrangement f the pyridine‐N‐oxide 6 to the 3‐hydroxypyridine 7 with Ac2O and a modified Curtius rearrangement of the acid 19 and subsequent diazotation and hydrolysis to the same pyridoxine precursor 7, respectively. The intermediate 7 is transformed to 1 by well‐known procedures.
Novel, racemic or nearly‐racemic antibacterial bromo‐ and chloroquinols and γ‐lactams of the verongiaquinol and the cavernicolin type from the marine sponge Aplysina (= Verongia) cavernicola
Authors: D'Ambrosio Michele , Guerriero Antonio , Pietra Francesco 
Published: December 2004

AbstractButanolic extracts of the Mediterranean sponge Aplysina (= Verongia) cavernicola have given, by reverse‐phase HPLC, the antibacterial quinols (±)‐3‐bromoverongiaquinol (= (±)‐3‐bromo‐1‐hydroxy‐4‐oxo‐2,5‐cyclohexadine‐1‐acetamide; 1d) and (±)‐3‐bromo‐5‐chloroverongiaquinol (= (±)‐3‐bromo‐5‐chloro‐1‐hydroxy‐4‐oxo‐2,5‐cyclohexadine‐1‐acetamide; 1c) besides the products of their formal cyclization 5‐chlorohexadiene‐1‐acetamide; 1c) besides the products of their formal cyclization 5‐chlorocavernicolin (= 5‐cloro‐3,3a,7,7aβ‐tetrahydro‐3aβ‐hydroxy‐2,6(1H)‐indoledione; 6), the C(7)‐epimerizing 7β‐bromo‐5‐chlorocavernicolin (=7 β‐bromo‐5‐chloro‐3,3a,7,7aβ‐tetrahydro‐3aβ‐hydroxy‐2,6(1H)‐indoledione; 4a and 7α‐bromo‐5‐chlorocavernicolin (4b), and the C(7)‐epimerizing 5‐bromo‐7β‐chlorocavernicolin ( = 5‐bromo‐7β‐chloro‐3,3a,7,7aβ‐tetrahydro‐3aβ‐hydroxy‐2,6(1H)‐indoledione; 5a) and 5‐bromo‐7α‐chlorocavernicolin (5b). The latter four were isolated as mixtures of C(7)‐epimerizing monoacetates 4a′/4b′ and 5a′/5b′. Both 1 and 1c proved to be racemic from NMR examination of their esterification products with (–)‐methyl‐oxyacetic acid, whilst 6 had a ca. 6% enantiomeric purity as shown by a 1H‐NMR study of its monoacetate 6′ in the presence of a chiral shift reagent. These chiroptical data of the first chiral quinols from the Verongida and of 6 suggest phenol oxidative routes from tyrosine precursors for their formation. In view of their bioactivities, 1d and 1c have been synthesized from (p‐hydroxyphenyl)acetic acid byt phenol oxidative routes.
Aminierende, reduktive Kupplung aromatischer Aldehyde mit Tris(dialkylamino)methylvanandium (IV) zu N,N,N′,N′‐Tetraaalkyl‐1,2‐diaryläthylendiaminen
Authors: Imwinkelried René , Seebach Dieter 
Published: December 2004

AbstractAminative Reductive Coupling of Aromatic Aldehydes to N,N,N′,N′‐Tetraalkyl‐1,2‐diarylethylenediamines, Induced by Tris(dialkylamino)methylvanadium (IV)In a novel type of reaction, certain aromatic aldehydes (benzaldehyde, p‐methoxybenzaldehyde, 1‐naphthaldehyde, furan‐2‐carbaldehyde) and secondary amines are coupled to give N,N,N′,N′‐tetraalkyl‐1,2‐diarylethylenediamines 1–6. The reagents are tris(dialkylamino)methylvanadium(IV) compounds (cf. Eqn. 2). These are generated in situ either from isolable chlorotris(dialkylamino) vanadium(IV) (Eqn. 3), or preferably, from an Et2O/pentane solution of VCl4 which is treated sequentially with 3 equiv. of lithium dialkylamide, 1 equiv. of MeLi, and 0.8 equiv. of an aromatic aldehyde, to give the products 1–6 in a one‐pot preparation (Scheme 2). The yields range from 14 to 54%. The diastereoisomeric mixtures (meso‐ and (±)‐forms) obtained are separated by chromatography (Al2O3, petroleum ether/Et2O/Et3N), and the pure stereoisomers fully characterized. A mechanism of the reductive coupling induced by CH3V (NR2)3 is proposed (Scheme 1).
Über die Totalsynthese vo Betalainen
Authors: Hilpert Hans , Dreiding André S. 
Published: December 2004

AbstractOn the Total Synthesis of BetalainsImproved total syntheses of the red‐violet aglucone of the beet coloring matter and of the yellow cactus coloring matter indicaxanthine are presented. Formyl‐olefination of the piperidone‐diester 6 with the acetaldehyde synthon 5 led to the piperidylidene‐acetaldehyde derivative 8, which was converted into the 2,4,4‐trimethylsemicarbazone of rac‐betalamic acid dimethyl ester (10) by treatment with t‐BuOCl and then Et3N. Exchanging the semicarbazone moiety with the (S)‐cyclodopa derivative 18, with (S)‐proline (19) and with indoline (20) transformed 10 to betanidin (21/22), to indicaxantihin (23/24) and to rac‐indo‐betalaine (25), respectively. The latter, a new, relatively stable betalaine, was hydrolyzed and esterified to rac‐betalamic acid dimethyl ester (29). Under the influence of NH3/MeOH, 26 (the dimethyl ester of 25) was dehydrogenated spontaneously to indo‐neobetalaine dimethyl ester (27).Synthetic betanidin consisted of a 4:6 mixture of the (natural) (2S, 15S)‐ (21) and the (2S, 15R)‐isomer (22) and both of a 75:25 mixture of the (E)‐ and the (Z)‐isomer. Synthetic indicaxanthin (23/24) and the indo‐betalaine (25) represented a 65:35 and a 70:30 mixture, respectively, of (E)‐ and the (Z)‐isomers. All (E)‐ and (Z)‐isomers are rapidly interconvertible. Temperature‐dependent 1H‐NMR‐measurements of 25 established ΔG≠ = 84.7 kJ/mole for the (E)‐to‐(Z)‐conversion.The t‐BuOCl/NEt3 method for the introduction of an enaminic double bond was applied to the model transformations of the amines 6, 12 and 15 to the conjugated enamiens 11, 13 and 17, respectively.
Diastereoselektive synthese neuartiger Mannich‐Basen mittels titanderivaten, vorläufige mitteilung
Authors: Seebach Dieter , Betschart Clauida , Schiess Martin 
Published: December 2004

AbstractDiastereoselective Synthesis of Novel Mannich (Bases1) through Titanium ReagentsTrichlorotitanium dialkylamino‐alkoxides (2; titanates of N, O‐hemiacetals) are generated either from the corresponding lithium alkoxides and titanium tetrachloride (Scheme 1) or by addition of trichloro‐dialkuylamino‐titanium to aldehydes. The electrophilic (dialkylamino) alkylating reagents 2 are used to convert lithium enolates to β‐dialkylamino‐ketones and ‐esters 5 (Mannich bases), see Scheme 2 and Table. One diastereoisomer of the products 5g–5p thus obtained with cyclohexenolate is formed preferentially (66‐84%). The configuration of the products of this first diastereoselective version of the Mannich reaction could not yet be determined. A typical procedure for carrying out the reaction is given.
Steuerung der katalytischen Pyridinsynthese aus Alkien and Nitrilien durch (η6‐Borinato)‐Liganden am Cobalt
Authors: Bönnemann Helmut , Brijoux Werner , Brinkmann Rainer , Meurers Willi 
Published: December 2004

AbstractControl of the Catalytic Synthesis of Pyridine from Alkynes and Nitriles by the (η6‐Borinato)‐Nigands at Cobaltη6‐Borinato groups as ligands at cobalt have unique effects on the chemo‐ and negioselectivity of the catalytic co‐cyclization of alkynes and nitriles. The turnover number of the conversion of acrylonitrile and acetylene to give 2‐vinylpyridine is considerably enhanced. Cyano compounds wih polar substitutents such as amino or thio groups can also be reacted. The homogeneous reaction of HCN with acetylene giving pyridine has been achieved for the first time.
Synthesen makrocyclischer Lactone durch Ringerweiterung Herstellung von (±)‐Phoracantholid I, (±)‐Dihydrorecifeiolid und (±)‐15‐Hexadecanolid
Authors: Kostava Kalina , Hesse Manfred 
Published: December 2004

Syntheses of Macrocyclic Lactones by Ring Enlargement Reaction Reaction. Preparation of (±)‐Phoracantholide I, (±)‐Dihydrorecifeiolide and (±)‐15‐HexadecanolideA general procedure for the synthesis of macrocyclic lactones is described. The Michael adducts of 2‐nitrocycloalkanones and acrylaldehyde were regiospecifically methylated with CH3Ti[OCH(CH3)2]3 or (CH3)2Ti[OCH(CH3)2]2 at the aldehyde carbonyl group. Treatment of the so‐formed alkohols with tetrabutylammonium fluoride gave the lactones enlarged by four ring members. This method was used to synthesize the 10‐membered (±)‐phoracantolide I (11), the 12‐membered (±)‐dihydrorecifeiolide (17), and (±)‐15‐hexadecanolide (24) in 52%, 26.5%, and 58.7% respectively.
Inductivity and Bridging in 2‐Bicyclo[2.2.2]octyl Cations. Polar Effects, Part 11
Authors: Grob Cyril A. , Sawlewicz Pawel 
Published: December 2004

AbstractThe solvolysis rates and products of several 6‐substituted 2‐exo‐ and 2‐endo‐Bicyclo[2.2.2]octyl p‐toluenesulfonates, 12 and 13, respectively, are reported. Inductivity, as measured by the reaction constants ρI, is considerably less in the exo‐series 12 (ρI = −1.50) than in the corresponding 2‐exo‐norbornyl p‐toluenesulfonates 1 (ρI= −2.0). It is proposed that, for geometrical reasons, bridging of the cationic center C(2) by C(6) is not as strong in the bicyclooctane series 12 as it is in the norbornane series 1. On the other hand, inductivity is higher in the 2‐endo‐bicyclooctane series 13 (ρI= −1.0) than in the corresponding 2‐endo‐norbornane series 3 (ρI = 0.78), probably, because in the former case bridging of C(6) is less hindered by the departing anion. The relative yields of exo‐ and endo‐substitution products from the series 12 and 13, are in accord with graded bridging of C(6) in the incipient bicyclooctyl cations. But almost constant bridging of C(2) by C(7) is indicated in the ionization of the 2‐endo‐bicyclooctane series 13. Consequently, in the free unsubstituted bicyclooctane cation C(2) is bridged symmetrically by C(6) and C(7), in contrast to the current concept of ‘non‐classical’ two‐electron‐three‐center bonding.
Nature et stabilité des complexes métalliques de cryptands dinucléants en solution. I. Polyazapolyoxa macrotricycle cylindrique et monocycle constitutif
Authors: Arnaud‐Neu Francoise , Sanchez Maria , Yahya Raïda , Schwing‐Weill Marie‐José , Lehn Jean‐Marie 
Published: December 2004

Nature and Stability of Some Metallic Complexes of Dinucleating Cryptands in Solution. I. A Polyazapolyoxa Cylindrical Macrotricycle and its Monocyclic SubunitpH‐metry and UV spectrophotometry were used to study the complexing properties of the cylindrical macrotricycle, 1,7,13,19‐tetraaza‐4,16‐dioxa‐10,22,27,32‐tetraoxatricyclo[17.5.5.5]tetratriacontane (1) and of its constitutive monocyclic subunit, 1,7‐diaza‐4,10‐dioxacyclododecane (2) with some transition and heavy metal cations (Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+, Ag+), in aqueous medium 0.1M Et4NClO4, at 25°. The protonation constants of the ligands as well as the nature and the stabilities of the complexes formed in the pH‐regions studied were determined. The tricycle 1 only formed dinuclear M2L complexes with Cu2+, Zn2+, and Ag+, accompanied in the latter case by a protonated mononuclear MLH species, and with Cu2+ and Zn2+ at high pH‐values by dinuclear hydroxo complexes. Only mononuclear complexes were evidenced with the other cations, ML being accompanied either by protonated or hydroxy mononuclear species. The mononuclear complexes of 1, when they existed, were more stable than the corresponding complexes of 2, except for cobalt which formed complexes of comparable stability with both ligands. In the other cases (Cd2+, Pb2+, Ag+), the stability differences between the complexes of 1 and 2 increased with the size of the cation.
Stoffwechselprodukte von Mikroorganismen. 232. Mitteilung. (E)‐3‐(1H‐Pyrrol‐3‐yl)‐2‐propensäure und (E)‐3‐(1H‐Pyrrol‐3‐yl)‐2‐propensäureamid aus Streptomyces parvulus, Stamm Tü 2480
Authors: Keller‐Schierlein Walter , Müller André , Hagmann Leonhard , Schneider Ursula , Zähner Hans 
Published: December 2004

(E)‐3‐(1H‐Pyrrol‐3‐yl)‐2‐propenoic Acid and (E)‐3‐(1H‐Pyrrol‐3‐yl)‐2‐propenamide from Streptomyces parvulus, Strain Tü 2480The title compounds were isolated from cultures of Streptomyces parvulus. They give a deep blue colour reaction with Ehrlich reagent. Their structures were elucidated by spectroscopy and comparison with synthetic samples. They do not show any antimicrobial activity.
Photochemische Synthesen potentiell hypoglykämisch wirkender 3‐Oxazoline
Authors: Pfoertner Karl‐Heinz , Bernauer Karl , Kaufmann Franz , Lorch Eckehard 
Published: December 2004

Photochemical Syntheses of 3‐Oxazolines which Possibly Exhibit Hypoglycemic ActivityReactions of photochemically generated benzonitrile methylides 2 with carbonyl compounds 3 yielded 3‐oxazolines of the types 5 and 6 (Scheme 1). Photooxidation of 5‐[p‐(dimethylamino)phenyl]‐2,2‐dimethyl‐4‐phenyl‐3‐oxazoline (5a) gave 4′‐(2,2‐dimethyl‐4‐phenyl‐3‐oxazolin‐5‐yl)‐N‐methylformanilide (6r) which could be transformed to 2,2‐dimethyl‐5‐[p‐(methylamino)phenyl]‐4‐phenyl‐3‐oxazoline (6s) by photodecarbonylation. Thirty 3‐oxazolines of types 5 and 6 have been synthesized and tested by oral and/or intraperitoneal administration to starved rats and obese‐hyperglycemic mice.
Nature et stabilité des complexes métalliques de cryptands dinucléants en solution. III. Le monocycle [22]‐Py2N4
Authors: Arnaud‐Neu Françoise , Sanchez Maria , Schwing‐Weill Marie‐José 
Published: December 2004

Nature and Stability of Some Metallic Complexes of Dinucleating Cryptands in Solution III. The Monocycle [22]‐Py2N4The nature and stability of complexes formed by a new 22‐membered monocycle L = [22]‐Py2N4 with the cations Mn+ = Cu2+, Co2+, Ni2+, Zn2+, Cd2+, Pb2+, and Ag+ have been determined in aqueous solutions (0.01M NaClO4, 25°) by pH‐metry and also, for the copper system, by UV‐absorption spectrophotometry. The stepwise protonation constants of the four amine functions of L were 9.1, 8.3, 7.1 and 3.7 logarithms units, respectively. No evidence was found for the protonation of the two pyridine nitrogen atoms. Mononuclear complexes MLn+ were identified in all systems investigated, but the dinuclear species M2L2n+ were only found with Cu2+ and Ag+. The logarithms of the overall stability constants for the copper and silver complexes are CuL2+, 12.9; Cu2L4+, 18.6; Agl+, 6.3; Ag2L2+, 10.9, respectively. Mononuclear hydroxy species MLOH(n−1)+ were identified in all systems except those of copper and silver. No dinuclear hydroxy complexes were detected. The complexing properties of L are compared to those of the large and less rigid bis‐dien.