bluuebunny/crossref_metadata_2025_split huggingface dataset:
Organische Phosphorverbindungen. XXVII Die direkte Synthese von Tetramethylphosphoniumhalogeniden
Authors: Maier Ludwig 
Published: December 2004

AbstractThe reaction of methyl chloride and methyl bromide with white phosphorus is studied under a variety of conditions, and the conditions giving a high yield of tetramethylphosphonium chloride and bromide are established. Thermal decomposition of [(CH3)4P]+Cl− gives (CH3)3P and CH3Cl, and alkaline decomposition of [(C4H9)3(C12H25)P]+Cl− gives C4H10 and (C4H9)2(C12H25)PO.
Die Cardenolide von Antiaris toxicaria LESCH Identifizierung von «Bogorosid» mit Convallosid sowie Isolierung und Partialsynthese von Gluco‐periplorhamnosid. Glykoside und Aglykone, 283. Mitteilung
Authors: Brandt R. , Kaufmann H. , Reichstein T. 
Published: December 2004

AbstractBogoroside, a hitherto unidentified glycoside from Antiaris toxicaria LESCH, is shown to be identical with convalloside. Reduction of the aldehyde group in convalloside to the methyl group yielded gluco‐periplorhamnoside, which could also be isolated from the sap of Antiaris toxicaria.
Notiz über thermische Ummethylierungsreaktionen. 5. Mitteilung über das massenspektrometrische Verhalten quartärer Stickstoffverbindungen
Authors: Hesse M. 
Published: December 2004

AbstractDie beiden Methylgruppen von Yohimbin‐methochlorid (1) sind thermisch austauschbar, was an Hand der trideuterierten Verbindung 2 massenspektrometrisch gezeigt wird. Die N(b)‐Trideuteromethylgruppe von 2 ist auch auf das «dimere» Indolalkaloid Voacamin (3) thermisch übertragbar.
Die Röntgenstrukturanalyse von 17β‐Bromacetoxy‐ 9β, 10α‐androst‐4‐en‐3‐on
Authors: Oberhänsli W. E. , Robertson J. Monteath 
Published: December 2004

AbstractThe structure of 17β‐bromacetoxy‐9β, 10α‐androst‐4‐en‐3‐one has been determined by three‐dimensional X‐ray crystallographic methods. The crystals of the restrosteroid belong to the orthorhombic space group P212121 with four molecules per unit cell. The cell constants are a = 11.32 Å, b = 13.71 Å and c = 12.52 Å. The absolute configuration of the molecule has been determined by the anomalous dispersion method. Bond length, bond angles and distances of atoms from ‘best planes’ are given. Ring A represents a distorted half‐chair, ring B and C a chair and ring D an envelope conformation. The molecule shows, contrary to normal 9α, 10β‐steroids, a bent shape.
Protonenresonanzspektroskopische Untersuchungen an Bicyclo [2.2.1]heptan‐ und Bicyclo[2.2.2]octan‐Derivaten: Einfluss von Substituenten auf die chemische Verschiebung
Authors: Pretsch E. , Immer H. , Pascual C. , Schaffner K. , Simon W. 
Published: December 2004

AbstractThe influence of substituents on the chemical shifts of protons in bicyclo[2.2.1]‐heptanes and bicyclo[2.2.2]octanes is discussed. A linear correlation between the change in chemical shift of a proton, due to a neighbouring methyl group, and the distance between this proton and the methyl group is obtained.
Über in 11‐Stellung amino‐substituierte Dibenzo[b,f]‐1, 4‐thiazepine und ‐oxazepine. 9. Mitteilung über siebengliedrige Heterocyclen
Authors: Schmutz J. , Künzle F. , Hunziker F. , Gauch R. 
Published: December 2004

AbstractNeuroleptics are found in the 11‐amino substituted dibenzo[b,f]‐1, 4‐thiazepine and dibenzo[b,f]‐1, 4‐oxazepine series III. They may be synthesized by aminolysis of the iminochlorides VI and/or by Bischler‐Napieralski ring closure of the urea II with POCl3.
Über die photochemische Cyclisierung von 2‐Allylphenolen
Authors: Fráter Gy. , Schmid H. 
Published: December 2004

AbstractA series of 2‐allyl‐phenols and 2‐but‐3′‐enyl‐phenol were photochemically rearranged to the corresponding cyclic ethers. The isomer distribution was shown to be similar to that observed for the acid catalysed cyclisation.
Recherches sur la formation et la transformation des esters LXXII. Aryl(ou aralcoyl ou alcoyl)amino‐2‐tétrahydro‐m‐thiazines ou aryl(ou aralcoyl ou alcoyl)amino‐2‐dihydro‐Δ2‐m‐thiazines et dérivés
Authors: Cherbuliez Emil , Baehler Br. , Espejo O. , Jindra H. , Willhalm B. , Rabinowitz J. 
Published: December 2004

Abstract3‐Aminopropanol reacts with aryl(or aralkyl or alkyl)isothiocyanates RNCS to yield the corresponding thio‐ureas RNHCSNH(CH2)3OH which, refluxed with hydrochloric acid, are cyclized by elimination of water. The cyclization products are identical with the hydrothiazines resulting by elimination of sulfate or phosphate from the sulfuric or phosphoric monoesters of these thio‐ureas. The resulting hydrothiazines are either 2‐(R‐imino)‐tetrahydro‐m‐thiazines (I) or 2‐(R‐amino)‐dihydro‐Δ2‐m‐thiazines (II). Their structure has been established by comparison of their spectra with those of model compounds in one of which the CN double bond is certainly endocyclic (2‐methyl‐dihydro‐Δ2‐m‐thiazine), the other presenting an exocyclic CN double bond (3‐methyl‐2‐phenylimino‐tetrahydro‐m‐thiazine). When R is an aryl group, the CN double bond is exocyclic (structure I with >CNAr), and one may presume that this structure is stabilized by resonance. When R is an aralkyl or an alkyl group, the CN double bond is endocyclic (structure II). The nmr spectra were taken with three types of solvent: CDCl3 or CCl4; (CD3)2SO; CF3COOH. In CF3COOH solution the benzylic protons of the hydrothiazine with R = pFC6H4CH2 couple with NH (J=5,5cps) which confirms the endocyclic position of the CN double bond in this case.
Les spectres de masse dans l'analyse 9e communication [1] Le réarrangement de doubles liaisons sous bombardement d'électrons
Authors: Willhalm B. , Thomas Alan F. 
Published: December 2004

AbstractUsing suitably deuteriated olefins, it is shown that electron bombardment of compounds having double bonds exocyclic to six‐membered rings apparently causes migration of the double bond into the ring. Isopropenylcyclohexanes, on the other hand, appear to behave as if the radical were fixed on the terminal carbon, while the charge migrates by 1,2 hydrogen transfers.
Die Bestimmung der Energiebarriere für die gehinderte interne Rotation in N, N‐Dimethylformamid durch Protonenresonanz‐Spektroskopie
Authors: Conti F. , von Philipsborn W. 
Published: December 2004

AbstractA re‐determination of the energy barrier for the internal rotation of N, N‐dimethylformamide has been carried out by proton magnetic resonance under refined experimental conditions. Consistent data have been obtained for ΔE, ΔG≠, and v0 from different experiments utilizing 60 Mc/s and 100 Mc/s spectrometers including homonuclear double resonance and the use of deuterium substitution. The results are compared with the range of values previously reported in the literature.
Interaction entre les phosphites alcoylés et le groupe carbonyle; trransformation des phosphites méthyliques dans l'acide acétique
Authors: Chopard P. A. 
Published: December 2004

AbstractIn acetic acid, trimethyl phosphite dealkylates and simultaneously forms dimethyl (1‐dimethoxyphosphono‐ethyl) phosphate. This is interpreted as evidence of an attack at the carbonyl group of the carboxylic acid.
Studien über Benzthiazole als eventuelle orale Antidiabetica
Authors: Suter Hans , Zutter Hans 
Published: December 2004

AbstractEs wurden neue Vertreter der Benzthiazolyl‐harnstoffe, Benzthiazolylaminoessigsäureamide, Benzthiazolyl‐thioessigsäureamide, Benzimidazolyl‐thioessigsäureamide und Benzthiazolylsulfonyl‐harnstoffe synthetisiert. Keine der hergestellten Verbindungen war genügend hypoglykämisch, um eine eingehende Prüfung zu rechtfertigen.
Gas‐chromatographische Untersuchungen an Uronsäuren und Uronsäurederivaten
Authors: Raunhardt O. , Schmidt H. W. H. , Neukom H. 
Published: December 2004

AbstractDas gas‐chromatographische Verhalten der Per‐trimethylsilyl‐Derivate einiger natürlich vorkommender Uronsäuren bzw. Uronolactone, ihrer Salze, ihrer Reduktions‐(Onsäuresalze und‐γ‐lactone) und Oxydationsprodukte (Glycarsäuren bzw. ihre Salze und Lactone) sowie ihrer Reaktionsprodukte mit Methanol wurde auf den Silikongummi‐Kolonnen SE‐52 und SE‐30 untersucht. Die beim Kochen von D‐Mannuron, D‐Glucuron und L‐Guluronsäure mit 2proz. methanolischer Salzsäure entstehenden Glycosidgemische wurden nach der Silylierung gas‐chromatographisch analysiert und die prozentuale Verteilung der auftretenden Pike nach Erreichen des Gleichgewichtes bestimmt. Anhand der gefundenen, auf meso‐Erythrit als internen Standard bezogenen Retentionszeiten wird die Trennbarkeit der Uronsäuren diskutiert.
Synthèses stéréosélectives de deux trioxydes C18H30O3 stéréo‐isomères, d'ambréinolide et de sclaréol‐lactone à partir de dérivés du (+)‐manool
Authors: Demole Edouard , Wuest Hans 
Published: December 2004

AbstractAmbreinolide, sclareol‐lactone and a pair of new trioxides C18H30O3 have been synthesized from suitable derivatives of (+)‐manool through stereoselective reactions.
Synthese von 7α‐Methyl‐3‐oxo‐Δ4,9,11‐19‐norandrostatrienen. Über Steroide, 211. Mitteilung
Authors: Wieland P. , Anner G. 
Published: December 2004

AbstractThe easy conversion of 3‐oxo‐Δ5(10),9(11)‐19‐norsteroids into 3‐oxo‐Δ4,9,11‐19‐norsteroids by subsequent treatment with a peracid, aluminium oxide, and boron trifluoride is described.
De la chimie des ptérines. 20e communication [1]. Obtention et comportement chimique de diphényl‐6,7‐tétrahydro‐5,6,7,8‐ptérines substituées ou non
Authors: Viscontini M. , Okada T. 
Published: December 2004

AbstractLes diphényl‐6, 7‐, méthyl‐5‐diphényl‐6, 7‐ et méthyl‐8‐diphényl‐6, 7‐tétrahydro‐5,6,7,8‐ptérines ont été obtenues par reduction au NaBH4 des ptérines ou dihydroptérines correspondantes. Alors que la première et la troisième sont facilement réoxydées en dihydro‐7, 8‐ptérines, la méthyl‐5‐diphényl‐6, 7‐tétrahydroptérine, traitée par O2 ou par H2O2, fixe un atome d'oxygène pour donner la N(2′)‐déhydro‐hydroxy‐4a‐méthyl‐5‐diphényl‐6, 7‐tétrahydroptérine, stable. Tous ces corps ont été caractérisés par analyse élémentaire et par leurs spectres UV., de RMN. et de masse.
Organische Phosphorverbindungen XXIX. Eine neue Methode zur Darstellung von dialkylaminomethylsubstituierten Phosphonig‐ und Phosphinsäuren der allgemeinen Formel R2NCH2PH(O)OH und (R2NCH2)2P(O)OH [1]
Authors: Maier Ludwig 
Published: December 2004

AbstractA new method for the preparation of dialkylaminomethyl‐phosphonous and‐phosphinic acids, R2NCH2P(O)H(OH) and (R2NCH2)2P(O)OH, is described. This involves reaction of hypophosphorous acid with hydroxymethyl‐dialkyl‐amines or a mixture of formaldehyde and a secondary amine.

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and

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The crystalline acids form monohydrates which are stable up to the melting points of the acids. The IR. and 31P‐NMR. spectra are reported.
Zur massenspektrometrischen Eliminierung von Neutralpartikeln aus Molekel‐ und Fragment‐Ionen
Authors: Bruderer H. , Richter W. , Vetter W. 
Published: December 2004

AbstractThe possibility of elimination reactions without participation of the positive charge and/or electron deficient centers, in particular the loss of RCOOH, was investigated for molecular and fragment ions. Such processes, which could be referred to as quasithermal or quasi‐photochemical reactions, were found to be absent or insignificant.
Die Glykoside der Wurzeln von Kanahia laniflora (FORSSK.) R. BR. 1. Mitteilung: Isolierungen. Glykoside und Aglykone, 299. Mitteilung
Authors: Kapur B. M. , Allgeier H. , Reichstein T. 
Published: December 2004

AbstractThe roots of Kanahia laniflora (FORSSK.) R. BR. contain, in addition to small quantities of cardenolides, a large amount of ester glycosides which are difficulty separable from one another. However, two of these ester glycosides were obtained in a nearly pure form. The crude mixture of ester glycosides, after mild acidic hydrolysis, gave a mixture of acyl‐genins and three sugars: D‐oleandrose, D‐digitoxose and D‐canarose, all of which were obtained in crystalline form. Acetic acid, benzoic acid and another unidentified acid were obtained on alkaline hydrolysis of the mixture of acyl‐genins along with 17‐isolineolon, lineolon, deacetylmetaplexigenin and a small amount of sarcostin‐ketone. Besides these known genins, three probably new genins (α, τ, λ) were obtained in small, but crystalline amounts.
Die Cardenolide von Acokanthera oppositifolia (LAM.) CODD. 3. Mitteilung . Isolierung weitere Cardenolide und teilweise Strukturaufklärung. Glykoside und Aglykone, 301. Mitt.
Authors: Hauschild‐rogat P. , Weiss E. K. , Reichstein T. 
Published: December 2004

AbstractThe presence of 19 cardenolides in the extracts from the seeds of Acokanthear oppositifolia (Lam.) CODD could be traced by means of paper chromatography. Thirteen of these cardenolides could be isolated in crystalline form, acovenoside A (= 2) being by far the major component. Of the other 12 crystalline substances, 5 could be identified with known cardenolides: 2′ = acofrioside L, 3 = acolongifloroside H, 14 = acovenoside C, 15 = acolongifloroside K, 16 = ouabain. The substances 1′, 1″, 4, 6, 7, 8 and 13 are very probably new compounds. Four of these were given trivial names and the following structures were proposed: 1″ = oppovenoside, probably 10; 4 = oppofrioside (5); 6 = acotaloside (6); 13 = opposide, probably 12, cf. following publication [21]. Furthermore, the structure 8 has been proposed for acolongifloroside H.
Pyridinderivate als Komplexbildner VIII Die Herstellung je eines neuen vier‐ und sechszähnigen Liganden
Authors: Anderegg G. , Wenk F. 
Published: December 2004

AbstractThe synthesis of the new complexing agents tris‐(2‐pyridylmethyl)‐amine and N,N,N′,N′‐tetrakis‐(2‐pyridylmethyl)‐ethylenediamine is described, and their protonation constants are given.
3‐O‐Methl‐6‐desoxy‐L‐talose, Synthese und Identifizierung mit L‐Acovenose. Desoxyzucker, 43. Mitteilung
Authors: Kapur B. M. , Allgeier H. 
Published: December 2004

Abstract3‐O‐methly‐6‐deoxy‐L‐talose has been synthesized starting from 1, 2–5, 6‐di‐O‐isopropylidene‐α‐D‐allose (1). Methylation, selective acidic hydrolysis, sodium periodate oxidation and GRIGNARD reaction with CH3MgBr gave a mixture of the 1, 2‐isopropylidene derivatives of 3‐O‐methyl‐6‐deoxy‐D‐allose and 3‐O‐methyl‐6‐deoxy‐D‐allose (7) and 3‐O‐methyl‐6‐deoxy‐L‐talose (8) (L‐acovenose) could be obtained. Oxidation of the latter gave the corresponding crystalline lactone, which could be indentified with a sample obtained from natural L‐acovenose.
Die Pregnanderivate der Samen von Dregea abyssinica (HOCHST.) K. Schum. (Asclepiadaceae). II. Strukturbestimmungen Glykoside und Aglykone, 305. Mitteilung
Authors: Bhatnagar Ajay S. , Stöcklin W. , Reichstein T. 
Published: December 2004

AbstractThe total or partial structure determinations of some new components from Dregea abyssinica are reported. The four drebyssogenins (F, G, J and H) are esters of the drevogenins P (7) and D(9) and have the following structures: Drebyssogenin F (5) = 11‐O‐acetyl‐12‐O‐(α‐hydroxyisovaleryl)‐drevogenin P, drebyssogenin G (14) = 11‐O‐acetyl‐12‐O‐isovaleryl‐drevogenin D, drebyssogenin J (15) = 11, 12‐di‐O‐acetyl‐drevogenin D. Drebyssogenin K is a mixture of K1 (16) and K2 (17), the mono‐O‐tiglyl and mono‐O‐isovaleryl derivatives of drevogenin D respectively, with as yet undetermined position of the acyl residues. The drebyssosides 1, 2 and 3 are glycosides of trisaccharides. Drebyssoside 1 (2) is pachybiosyl‐cymarosyl‐drevogenin A, drebyssoside 2 (3) asclepobiosyl‐cymarosyl‐drevogenin A and drebyssoside 3 (6) pachybiosyl‐cymarosyl‐drebyssogenin F. Drebyssoside 4 is a mixture of at least two components and contains the same aglycones and the same sugar units as the drebyssosides 1 and 3, but is different from them. The full structure of the two sugars (drebyssobiose (25) and sugar T (24)) has not been determined; it is only shown that both are disaccharides which contain 3‐O‐methyl‐6‐deoxy‐allose linked to a 2‐deoxyhexose.
Isolierung, Aminosäurezusammensetzung und tryptischer Abbau von Thyrocalcitonin aus Schweineschilddrüsen
Authors: Franz J. , Rosenthaler J. , Zehnder K. , Doepfner W. , Huguenin R. , Guttmann St. 
Published: December 2004

AbstractHog thyrocalcitonin has been isolated in the form of an homogeneous peptide. After digestion with trypsin three fragments have been separated by paper electrophoresis. the amino acid composition of intact thyrocalcitonin and of the three tryptic fragments is given in a table.
Über die Synthese von 1,4‐Benzoxazepinen und ihre Umlagerung in Isochinoline
Authors: Schenker K. 
Published: December 2004

AbstractThe syntheses of 3‐phenyl‐5‐oxo‐4, 5‐dihydro‐1,4‐benzoxazepine (2) and ‐3‐phenyl‐5‐ethoxy‐1,4‐benzoxazepine (14) are described. 2 rearranges under the influence of sodamide into the isoquinoline derivatives 4, 5 and 6 respectively; 14 is converted quantitatively into 1‐ethoxy‐3‐phenyl‐4‐hydroxy‐isoquinoline (16) in boiling methanol, even in the absence of a strong base. Possible reaction mechanisms are discussed.
Notiz über die Synthese von Iso‐, Noriso‐ und Desäthyl‐tuboflavin
Authors: Rosenkranz H. J. , Schmid H. 
Published: December 2004

AbstractTreatment of 4,5 ‐dihydrocanthin‐6‐one (V) (prepared from synthetic canthinone (IV)) with ethyl or methyl magnesium iodide and methanolic hydrochloric acid yielded the ethyl or methyl compounds VI and IX. Oxidation of the latter compounds with selenium dioxide in dimethylformamide gave rise to the Pleiocarpa alkaloids isotuboflavine (II) and norisotuboflavine (III) in low yields. Deethyltuboflavine (VIII) was isolated as a byproduct from further oxidation of norisotuboflavine.
Über die Struktur von Imidazolin‐ und Imidazolidin‐Derivaten aus 2‐Amino‐2‐desoxy‐hexosen
Authors: Fritz H. , Morel Ch. J. , Wacker O. 
Published: December 2004

AbstractIn earlier publications [1] [2] [3] [4] a pyranoid structure has been proposed for the sugar moiety of imidazoline and imidazolidine derivatives from D‐glucosamine. But by NMR.‐spectra and periodate oxidation the sugar moiety of these compounds and of similar derivatives from other 2‐amino‐2‐deoxy‐sugars is now shown to be of furanoid structure.
Synthesen von Indolen mit (2‐Aminoäthyl)‐, (2‐Aminopropyl)‐oder Alkanolamin‐Seitenketten am Sechsring. 5. Mitt. über synthetische Indol‐Verbindungen [1]
Authors: Troxler F. , Harnisch A. , Bormann G. , Seemann F. , Szabo L. 
Published: December 2004

Abstract4‐, 5‐, 6‐ and 7‐cyanoindoles are converted in excellent yields into the corresponding formylindoles by sodium hypophosphite/nickel according to the method of BACKEBERG and STASKUN. Condensation of these formylindoles with nitromethane or nitroethane affords the related nitrovinyl‐indoles, which are reduced to the aminoalkyl‐indoles quoted in the title by means of lithium aluminium hydride.On the other hand, 5‐chloroacetyl‐indole is aminated by reaction with various secondary amines, and the aminoketones formed are reduced to the corresponding 5‐(2‐amino‐1‐hydroxy‐alkyl)‐indoles. Condensation of 1‐acetyl‐7‐hydroxy‐indoline with chloroacetyl chloride according to FRIEDEL‐CRAFTS yields the 1‐acetyl‐4‐chloroacetyl‐7‐hydroxy‐indoline, which is transformed into indoline derivatives carrying a 2‐amino‐1‐hydroxyethyl side‐chain in position 4.
Kinetische Untersuchungen über Substitutionsreaktionen an Metallkomplexen. 7. Mitteilung [1]. Kinetik und Mechanismus der Reaktion von Methoxyorganylcarbenpentacarbonyl‐chrom‐Verbindungen mit tertiären Phosphinen
Authors: Werner H. , Rascher H. 
Published: December 2004

AbstractThe kinetics of the reactions of methoxyorganylcarbenechromium complexes Cr(CO)5C(OCH3)R′ (R′ = CH3, C6H5) with tertiary phosphines PR3 have been studied by means of spectrophotometric methods. The reaction products of general composition cis‐Cr(CO)4(PR3)C(OCH3)R′, Cr(CO)5PR3 and trans‐Cr(CO)4(PR3)2 are formed by cleavage of both the Cr‐CO and the Cr‐C(carbene) bonds. The two‐term rate law indicates two parallel, dissociative and associative, mechanisms. The kinetic data will be discussed in connection with the concept of labilising and non‐labilising ligands.
Substitution der 6‐Aminopenicillansäure am Kohlenstoffatom 6
Authors: Reiner R. , Zeller P. 
Published: December 2004

AbstractThe hydroxyalkylation of the penicillin nucleus at C‐6 with benzaldehyde and formaldehyde is reported. 6‐aminopenicillanic acid (6‐APA) (2) was used as starting material. Protection of the functional groups and activation of the C‐6 position were effected by converting 6‐APA successively into the Schiff base 13, the methyl ester 14 and the copper complex 15. The latter gave with benzaldehyde the C‐6 monosubstituted complex 17, and with formaldehyde the disubstituted complex 18. The direct α‐hydroxybenzylation of 6‐APA at C‐6 was also carried out with an excess of benzaldehyde at pH 7,5 leading to the SCHIFF base 19. Mild hydrolysis of 19 gave 6‐amino‐6‐(α‐hydroxybenzyl)‐penicillanic acid (21). Phenylacetylation of the latter yielded the penicillin G analogue 22. Direct reaction of 6‐APA with formaldehyde took place only in the presence of salicylaldehyde, giving the oxazolidine 24, from which the amino acid 25 could not be obtained. The new compounds showed only weak antibacterial activity as compared with penicillin G.
Über die Entstehung von α‐Keto‐carbonium‐Ionen bei der säurekatalysierten Hydrolyse von Diazoketonen. (Vorläufige Mitteilung)
Authors: Dahn H. , Gold H. , Ballenegger M. , Lenior J. , Diderich G. , Malherbe R. 
Published: December 2004

AbstractSecondary deactivated aliphatic diazo compounds (diazo‐ketones RCOCN2R′; diazo‐esters ROOCCN2R′; 1, 1, 1‐trifluoro‐2‐diazopropane) are hydrolysed by the ASE2 mechanism comprising rate determining protonation of the substrate, followed by decomposition. Product analysis shows that the decomposition of the secondary diazonium ions is monomolecular, without intervention of a nucleophile.The corresponding primary diazo compounds (RCOCHN2, ROOCCHN2 and CF3CHN2) are hydrolysed by the A‐2 mechanism comprising preequilibrium protonation; the primary diazonium ion reacts with a nucleophile in a bimolecular displacement step. The only exception observed is found in p‐nitrophenyl‐diazomethane, which follows ASE2 mechanism.The observations are discussed in terms of the stability of the corresponding secondary resp. primary α‐keto‐carbonium ions.
Synthese der Purpurin‐8‐carbonsäure; Beitrag zum Boletol‐Problem Vorläufige Mitteilung
Authors: Bräm A. , Eugster C. H. 
Published: December 2004

AbstractEine neue und in bezug auf die Stellung der Substituenten eindeutige Synthese von Methoxybenzanthronen wird beschrieben. Oxydativer Abbau an 1,8,10,11‐Tetramethoxybenzanthron führte zu 5,7,8‐Trihydroxy‐anthrachinon‐1‐carbonsäure; an 1,8,11‐Trimethoxyhenzanthron zu 5,8‐Dihydroxyanthrachinon‐1‐carbonsäure. 5,7,8‐Trihydroxy‐anthrachinon‐1‐carbonsäure ist weder mit «Boletol» noch mit «Isoboletol» von KÖGL & DEIJS identisch.Erneute Isolierung der mit Oxydasen blau werdenden Farbstoffe aus Boletus satanas, B. Iuridus und B. calopus gab kein «Boletol», sondern in Übereinstimmung mit den Ergebnissen anderer Autoren. Variegatsäure (Luridussäure) und weitere Verbindungen.Boletol ist vorderhand als Naturprodukt zu streichen.
De la chimie des ptérines 27e communication, préliminaire. [1] Sur l'éliminetion du reste N(5)‐méthyle chez les méthyl‐5‐tétrahydro‐5,6,7,8‐ptérines
Authors: Viscontini M. , Okada T. 
Published: December 2004

AbstractEn milieu acide la méthyl‐5‐diphényl‐6, 7‐dihydro‐5, 6‐ptérine perd rapidement son reste méthyle et un H pour être transforméee en diphényl‐6, 7‐ptérine. Il semble qu'un des produits intermédiaires de la transformation soit la méthyl‐5‐diphényl‐6, 7‐dihydro‐5, 8‐ptérine. On suppose qu'à partir de cette ptérine il se forme un radical‐cation perdant spontanément un proton en N(8) et le radical méthyle, phénomène qui pourrait bien être lié à la transéthylation biologique catalysée par les méthyl‐5‐ptérines hydrogénées.
Neue Antipodenpaare zur optischen Spaltung recemischer Basen
Authors: Felder E. , Pitrè D. , Boveri S. 
Published: December 2004

AbstractAs new reagents for optical resolution of racemic bases the enantiomorphs of N‐(1‐phenyl‐ethyl)‐succinamic acid (I) and N‐(1‐phenyl‐ethyl)‐phthalamic acid (II) have been prepared. Optical resolution with I of (1‐phenyl‐ethyl)‐amine, 2‐amino‐butane‐1‐ol, threo‐1‐(4‐nitrophenyl)‐2‐amino‐propane‐1, 3‐diol and with II of 1‐phenyl‐2‐amino‐propane is described.