bluuebunny/crossref_metadata_2025 huggingface dataset:
Reaction of 3‐(o‐chlorobenzylidene)‐2,4‐dioxopentanoic acid with hydroxylamine hydrochloride. Revised structure tor azeto[3,2‐d]isoxazoline
Authors: Kurihara Takushi , Mori Masanobu , Sakamoto Yasuhiko
Published: April 2009

Reaction of 3‐(o‐ehlorobenzylidene)‐2,4‐dioxopentanoic acid (1) with hydroxylamine hydro‐chloride in acetic acid gave 5‐(o‐chlorophenyl)‐3‐methyl‐4‐(α‐hydroxyimino)isoxazolineglyo‐xylic acid (5) and 3‐(o‐chlorobenzylidene)‐4‐hydroxyimino‐2‐oxopentanoic acid (2) in 57% and 7% yields. Pyrolysis of 5 afforded 5‐(o‐chlorophenyl)‐3‐methylisoxazole‐4‐carbonitrile (8), cis‐ and trans‐5‐(o‐chlorophenyl)‐3‐methylisoxazoline‐4‐carbonitriles (9,10), and 5‐(o‐chloro‐phenyl)‐3‐methylisoxazoline‐4‐carboxamide (11).
A novel synthesis of 1,4‐diarylpiperazines
Authors: Bissell Eugene R.
Published: April 2009

1,4‐Diarylpiperazines are readily prepared, generally in good yields, by the reaction of substituted aromatic amines with two thirds of an equivalent of tris(2‐chloroethyl)phosphate.
Mass spectral fragmentation pattern of 2,2′‐Bipyridyls. Part IX. 6‐Alkoxy‐2,2′‐bipyridyls
Authors: Keats N. G. , Summers L. A.
Published: April 2009

The mass spectral fragmentation patterns of 6‐methoxy‐, 6‐ethoxy‐ and 6‐propoxy‐2,2 ′‐bipyridyls are reported. The base peaks in the spectra of both the 6‐methoxy and 6‐ethoxy compounds are due to the M‐lion of 6‐methoxy‐2,2′‐bipyridyl, while the base peak with 6‐propoxy‐2,2‐ bipyridyl is due to a species formed by loss of C3H6 from the molecular ion.
Mass spectral fragmentation pattern of 2,2′‐Bipyridyls. Part X. trans‐1,2‐Di‐(2‐pyridyl)ethylene
Authors: Keats N. G. , Summers L. A.
Published: April 2009

The base peak in the mass spectrum of trans‐1,2‐di‐(2‐pyridyl)ethylene is due to the M‐1 ion. A major fragmentation route involves loss of HCN from the M‐1 ion. Another important pathway involves rupture of one of the bonds linking a pyridine ring with the central CHCH group.
Synthesis of 5H‐Tetrazolo[1,5‐d] [1,4]benzodiazepin‐6(7H)ones
Authors: Peet Norton P. , Sunder Shyam
Published: April 2009

Syntheses of 5H‐tetrazolo [1,5‐d] [1,4 ]benzodiazepin‐6(7H)ones 2a‐d from 5‐(o‐aminophenyl)‐tetrazoles 1a‐d and bromoacetyl bromide are described. Compounds 2a‐d are representatives of a novel tricyclic ring system. Several alternate methods for the synthesis of 2a‐d were attempted without success. Spectral evidence for structural assignments 2a‐d is presented. Chemical evidence for these assignments includes the transformation of 2a to 6‐(2,2‐dimethylhydrazino)‐5H‐tetrazolo[1,5‐d] [1,4]benzodiazepine (19) via the thione analog of 2a (18).
3‐Monosubstituted and 3,6‐Unsymmetrically disubstituted 1,2,4,5‐Tetrazines. A general method of synthesis
Authors: Mangia Alberto , Bortesi Fulvio , Amendola Umberto
Published: April 2009

A stepwise procedure has been developed for the synthesis of 3,6‐unsymmetrically disubstituted‐ or 3‐monosubstituted‐1,2,4,5‐tetrazines, based upon the facile substitution either of an alkylthio group in 3,6‐bis(alkylthio)‐1,2,4,5‐tetrazines (1) and (2) by nitrogen nucleophiles, particularly by hydrazine, or of a bromo group, obtained by oxidation of a hydrazino group or by an independent synthesis, by carbon nucleophiles. The ultraviolet‐visible spectra and some nuclear magnetic resonance properties are discussed.
Synthesis and conformational analysis of isomeric 3‐propananilidotropanes
Authors: Bagley Jerome R. , Riley Thomas N.
Published: April 2009

The isomeric 3‐anilino and 3‐propananilidotropanes have been synthesized and obtained in isomerically pure form. The configurations and solute conformations of these isomers were studied via glc and nrar analysis. The 3β‐isomers have been shown to exist in the normal piper‐idine chair conformation whereas the 3α‐anilino tropane exists in a flattened piperidine chair conformation and the 3α‐propananilidotropane isomer preferentially exists in a conformation in which the piperidine ring system is a boat.
Studies on the chemistry of 2,3,5,6‐tetrahydro‐6‐phenylimidazo[2,1‐b]‐thiazole II. Reaction with nucleophiles
Authors: Bigg D. C. H. , Purvis S. R.
Published: April 2009

The title compound behaves as an ambident electrophile which reacts with alkylthiols, thio‐phenols, and sodium diethyldithiocarbamate to give 1‐(2‐substituted ethyl)‐4‐phenylimidazolidine‐2‐thiones by attack at C‐2. In contrast, the reaction with pyrrolidine involves attack at the bridgehead carbon atom, followed by elimination of thiirane, to give 4‐phenyl‐2‐(1‐pyrrolidino)‐imidazoline.
Pyrimido[5,4‐b]quinolines. II. Reactions at the heterocyclic ring‐carbon and nitrogen atoms
Authors: Levine E. M. , Chu C. K. , Bardos T. J.
Published: April 2009

10‐Chloro‐7,8‐dimethylpyrimido[5,4‐b]quinolin‐2,4(1H,3H)dione (I) was unreactive toward ammonia but it reacted with 2 molecules of n‐butylamine, presumably via Dimroth‐type ring‐opening and closure, to give the N3‐butyl, N10‐butylamino derivative (IV). In similar reactions of 10‐chloro‐2,4‐dimethoxy‐7,8‐dimethylpyrimido[5,4‐b]quinoline (II) only the 4‐meth‐oxyl was displaced by either ammonia or n‐butylamine. Alkyllithium reagents also displaced the 4‐methoxyl as well as added to the 3,4 double bond of II to yield the corresponding gem‐dialkyl substituted (C4) derivatives; the C10 chlorine remained unreactive. 2,4‐Dimethoxy‐7,8‐di‐methylpyrimido[5,4‐b]quinoline‐10‐one (III) could be alkylated only in the form of the thallium salt. Treatment of the benzyl derivative of III with methylmagnesium bromide led only to the displacement of the 4‐methoxyl by a methyl group.
Synthesis and chemical reactivity of some 1,2,4‐Thiadiazolo[2,3‐a]‐pyrimidines and related compounds
Authors: Korea B. , Stanovnik B. , Tišler M.
Published: April 2009

A novel synthetic approach for 1,2,4‐thiadiazolo[2,3‐a]pyrimidines, 1,2,4‐thiadiazolo[2,3‐c]‐pyrimidines and 1,2,4‐thiadiazolo[2,3‐b] indazoles is described. Several transformations of these heterocyclic systems are presented. 1,2,4‐Thiadiazolo[2,3‐a] pyrimidines undergo a very facile ring cleavage to give 3‐amino‐5‐carbethoxyamino‐1,2,4‐thiadiazole and similar ring opening was observed also with the isomerie [2,3‐c] system. On the other hand, 1,2,4‐thiadiazolo[2,3‐a]‐pyridines undergo under similar conditions cleavage of the thiadiazole part of the bicycle.
Sels de N‐alcoxypyridinium porteurs d'une fonction acide on ester au niveau d'un carbone α tertiaire. Synthèse et réactivite vis‐à‐vis des ions hydroxydes
Authors: Sliwa Henri , Tartar André
Published: April 2009

Alors que le N‐oxyde de pyridine ne réagit pas directement sur l'acide α‐bromo isobutyrique ou sur son ester éthylique, les adduits correspondants sont obtenus aisément, sous forme de nitrates cristallisés 1 et 2, en effectuant la réaction en présence de nitrate d'argent en solution dans l'acétonitrile. Bien que le sel à fonction ester 2 ne soit pas sensible à la solvolyse de la liaison O‐Cα et ne puisse donner la décomposition classique selon le mode A, l'étude cinétique de son ouverture par les ions hydroxydes ne peut ětre réalisée en l'absence de réaction parasite; l'hydrolyse de la fonction ester suivie de l'ouverture de la bétaïne résultante rend alors compte d'un ordre de réaction vis à vis des ions hydroxydes supérieur à 2. Cette réaction d ouverture entre en compétition avec une décomposition carboxylogue du mode A en dioxyde de carbone, acétone et pyridine lorsque le sel à fonction acide 1 est soumis à Faction des ions hydroxydes.
Synthesis of 1‐Methyl‐3‐pyrrolin‐2‐one
Authors: Zoretic Phillip A. , Soja P.
Published: April 2009

The synthesis of 1‐methyl‐3‐pyrrolin‐2‐one from the oxidative‐elimination of 1‐methyl‐3‐phenylselenenyl‐2‐pyrrolidinone and from the pyrolysis of 3‐phenylsulfinyl‐2‐pyrrolidinone is reported.
Methanolysis of 2‐Phenylfuro[3,4‐d] pyrimidine‐5,7‐dione
Authors: Schuian Thomas J.
Published: April 2009

Reported is the synthesis of 2‐phenylfuro[3,4‐d]pyrimidine‐5,7‐dione which reacts with methanol to give 5‐methoxycarbonyl‐2‐phenyl‐4‐pyrimidine carboxylic acid.
Synthesis of 6‐amino‐1,2,4‐triazolo[1,5‐a]pyrazin‐4(5H)one, a bridgehead analog of guanine
Authors: Pickering Michael V. , Campbell Marie T. , Witkowski J. T. , Robins Roland K.
Published: April 2009

The synthesis of 6‐amino‐1,2,4‐triazolo[1,5‐a]pyrazin‐4(5H)one, an analog of guanine with a bridgehead nitrogen, is described.
The Synthesis of 2‐Carbomethoxy‐2‐carbomethoxymethyl‐2,3‐dihydro‐4(1H)quinazolinones
Authors: Beam Charles F. , Park Charles A. , Heindel Ned D. , Fives William P.
Published: April 2009

The treatment of anthranilhydrazides with dimethyl acetylenedicarboxylate resulted in enamines that cyclized to the six‐membered quinazolinones instead of the seven‐membered benzodiazepines.
Structure verification of (Z)‐5,6‐dihydro‐8(7H)quinolinone thiosemicarbazone by x‐ray single crystal analysis
Authors: Korp J. D. , Bernal I. , Lemke T. L.
Published: April 2009

The crystal structure of (Z)‐5,6‐dihydro‐8(7H)quinolinone thiosemicarbazone has been determined by X‐ray single crystal analysis in order to confirm the identity of this analog of the antineoplastic agent 2‐formylpyridine thiosemicarbazone. In the solid state, the molecules are arranged in pairs held together by intermolecular S‐N hydrogen‐bonds. There is also an extensive intramolecular N‐N hydrogen‐bonding system.
Isothiazoles X. 3‐alkoxyisothiazole derivatives
Authors: Weiler Ernest D. , Hausman Martin , Miller George A.
Published: April 2009

Halogenation of a number of 3‐alkoxyisothiazoles, occurring exclusively in the 4‐position, followed by cyanation led to various carboxylic acid, carboxamide and amine derivatives. Subsequent dealkylation provided 4‐substituted‐4‐isothiazoIin‐3‐ones.
Potential psychotropic agents. 7‐Chloro‐9‐phenyl‐3,3‐diethyl‐3H‐pyrazolo‐[5, 1‐b]quinazolin‐10‐ium‐2‐olate and 9‐Chloro‐2,3,4,5‐tetrahydro‐1‐methyl‐3,3‐diethyl‐7‐phenyl‐1H‐benzo‐1,5,6‐triazonine‐2,4‐dione
Authors: Orzalesi Giovanni , Selleri Renato , Vittory Rodolfo Landi , Innocenti Franco , Grandolini Giuliano
Published: April 2009

2‐Amino‐5‐chloro‐α‐phenylbenzylidene hydrazone (1) or its methyl derivative 2 or acetyl derivative 10 react with diethylmalonic esters to give the corresponding malonyl derivatives 3, 4 and 8. These esters were hydrolyzed to the acids 5 and 6. Treating 5 with dehydrating agents the mesoionic compound 7‐chloro‐9‐phenyl‐3,3‐diethyl‐3H‐pyrazolo[5,1‐b]quinazolin‐10‐ium‐2‐olate (14) was obtained, while the methyl derivative 6 afforded the desired 9‐chloro‐2,3,4,5‐tetrahydro‐1‐methyl‐3,3‐diethyl‐7‐phenyl‐1H‐benzo‐1,5,6‐triazonine‐2,4‐dione (17). Some derivatives of these compounds were also described. The structures of the new compounds were confirmed by an alternative synthesis and by mass and prnr spectral data.
Condensation of ethyl 3‐pyridylacetate with ethyl phenylpropiolate
Authors: Al‐Jallo H. N. , Al‐Azawi F. N.
Published: April 2009

Ethyl phenylpropiolate reacted with ethyl 3‐pyridylacetate in the presence of sodium ethoxide to give ethyl 3,5‐diphenyl‐4‐carbethoxy‐6‐(3‐pyridyl)salicylate (III). Different derivatives for the product were prepared and their structures were elucidated on the basis of ir and nmr spectra.
Δ3‐ and Δ4‐1,2,4‐oxadiazolin‐5‐ and 3‐ones
Authors: Boyer Joseph H. , Ellis Peter S.
Published: April 2009

Preparations for 2,3‐diphenyl‐ and 2‐benzyI‐3‐phenyl‐Δ3‐1,2,4‐oxadiazolin‐5‐ones (3) and (4) and for 2,5‐diphenyl‐Δ4‐1,2,4‐oxadiazolin‐3‐one (7) are reported.
The configuration and solid state conformation of 3,7‐dihydroxy‐1,5‐bis(p‐bromophenyl)octahydro‐1,5‐diazocine
Authors: Peters Gary Y. , Jensen William P. , Worman James J. , Jacobson Robert A. , Nelson David A.
Published: April 2009

The crystal structure of 3,7‐dihydroxy‐1,5‐bis(p‐brornophenyl)octahydro‐1,5‐diazocine (4) has been determined from the three dimensional x‐ray diffraction data. This infers a similar structure for 3,7‐dihydroxy‐1,5‐diphenyloetahydro‐1,5‐diazocine (1). The molecules are in a twist crown conformation and the configuration of the hydroxyl groups on the 3,7‐positions is cis.
Synthesis of 3‐phenyl‐2H‐1,4‐benzoxazin‐2‐one. Revision of some structural assignments
Authors: Chioccara Francesco , Gala Francesco Delia , Novellino Ettore , Prota Giuseppe
Published: April 2009

The reported synthesis of 3‐phcnyl‐2H‐1,4‐benzoxazin‐2‐one (II) via brominution of o‐acel‐amidophenyl phcnaeyl ether (Scheme) leads in lael to the 7‐bromo‐3‐phenyl‐2H‐1,4‐benzoxazin‐2‐ol (VIII). The structure of the other synthetic intermediates is also revised and a one‐step synthesis of the lactone II is reported hy condensation of methyl phenylglyoxalale and o‐amino‐phenol.
L'ernploi du tétrafluoroborate de triéthyloxonium et ses limites, dans l'éthylation d'oxo‐2 indolinc earboxanilides et thioearboxanilides
Authors: Deberly Alain , Bourdais Jacques
Published: April 2009

La réaction du télrafluoroborate de Uriéthyloxonium (réaclif de Mcerwein) avec les oxo‐2 indolinc carboxanilides‐3 (4) conduit principalcment aux dérivés d'éthoxy‐2 indole, ainsi qu'á d'autres composés C‐ et O‐éthylés. Cependant, on observe également la formation de difluoro indolyloxyboranes, par réaction des anilides 4 avec le trifluorure de bore provenant de la decomposition, in situ, du réaetif de Meerwein. Ces résultats montrent certaines limites d'applications en synlhése de ce réactif.
Reaction of 3,6‐disubstituted 4‐nitropyridazine 1‐oxides with methanolic ammonia and liquid ammonia
Authors: Sakamoto T. , Van Der Plas H. C.
Published: April 2009

Reaction of 3‐chloro‐6‐methyW‐nitropyridazine 1‐oxide (5) with methanolic ammonia at 0° led to a replacement of the chlorine atom by a methoxy group as well as by an amino group. Reaction of the 3‐methoxy‐6‐methyl‐4‐nitropyridazine 1‐oxide (6) with the same reagent led to amino‐demethoxylation; this replacement reaction was very slow. Attempts to perform these reactions with liquid ammonia failed. Pmr spectroscopy of solutions of compound 6 in methanolic ammonia revealed that no σ‐adduct was present. However in liquid ammonia a 1:1 σ‐adduct at C‐5 i.e. 12b was formed. 3,6‐Dimethoxy‐4‐nitropyridazine 1‐oxide (7) gave with methanolic ammonia an amino‐demethoxylation at C‐6. No σ‐adduct could be detected by pmr spectroscopy. However, in liquid ammonia convincing pmr data were obtained showing the presence of a 1:1 σ‐adduct at C‐5.
Thieno [2,3 ‐b] pyridines and thieno [ 3,2 ‐b] pyridines by the method of gould‐jacobs
Authors: Khan Misbahul Ain , Guarçoni Antonio Elydio
Published: April 2009

Bis(2‐, and 3‐thienylammonium) hexachlorostannates were condensed with ethoxymethylene derivatives of active methylene compounds in pyridine. The resulting condensation products IVa‐IVc and Va‐Vc on heating under reflux in Dowtherm or diphenyl ether provided various 4‐hydroxythieno[2,3‐b] pyridines (Ia‐Ic) and 7‐hydroxythieno[3,2‐b]pyridines (IIa‐IIc). The compound Ic on further transformations gave yet other derivatives If‐Ik.
Imidazo [4,5‐c] ‐ and [4,5‐6] pyridines
Authors: Denzel Theodor , Höhn Hans
Published: April 2009

The synthesis of novel imidazo[4,5‐c]pyridines 11‐13 and imidazo[4,5‐b]pyridines 18‐20 is described using 2 as the starting material. The synthesis is generally applicable for the introduction of a wide variety of substituents.
The synthesis and reactivity of some 2‐amino‐5‐bromo‐],1,3,4‐thiadiazoles and the corresponding Δ2‐1,3,4‐thiadiazolines
Authors: Werber Giuseppe , Buccheri Francesco , Gentile Manlio
Published: April 2009

The synthesis of some 2‐amino‐5‐bromo‐1,3,4‐thiadiazoles is reported; these substrates are found to behave as ambidenl nucleophiles in alkylation, aeylation and nitrosation reactions, giving thiadiazoliens along with thiadiazole derivatives. This finding suggests amine‐imine tautomerism between these compounds and the corresponding Δ2‐1,3,4‐thiadiazolines.
Isomeric maleic anhydride adducts of phthalazine and pyridazine and their partial stereochemistry
Authors: Hocking M. B.
Published: April 2009

The addition of maleic anhydride to phthalazine is confirmed to form a five‐membered pyrrolidino ring fusion to phthalazine VI, rather than a pyridophthalazine II, by means of synthetic and degradative experiments, and proton and carbon‐13 nmr. Two of probable three isomers obtained have been isolated and the stereochemistry partially established. Comparison of the data obtained for this adduct with the data obtained for the adduct of maleic anhydride with pyridazine demonstrates that it too possesses the pyrrolidino ring fusion. Electron impact fragmentations of the two adducts are compared and are related to the breakdown of 1H,2H‐pyridazinone.
Recherches sur le benzofuranne. LX. Orientation de la dégradation alcaline des aroyl‐3 éthyl‐2 benzofurannes, selon la nature de leur groupe aroyle
Authors: Astoin Jacques , Demerseman Pierre , Riveron André , Royer René
Published: April 2009

Far dégradation alcaline suivie de recyclisation acido‐catalysée, les aroyl‐3 éthyl‐2 benzofurannes donnent des aryl‐2 benzofurannes, avec des rendements qui dépendent notamment de 1′effet stérique des substituants du groupe aroyle.

Ce precédé convient particuliérement pour la synthése de benzofurannes substitutés en 2 par un phényle encombré.
Optishift PMR spectroscopic studies on some quinoxaline amino esters and dipeptides
Authors: El‐Abadelah Mustafa M. , Sabri Salim S. , Tabba Hani D. , Duddeck Helmut
Published: April 2009

Optishift pmr spectral measurements on a series of N‐(2‐quinoxaloyl)α‐amino esters and the C3‐CH3 analogues indicate that their L‐isomers are optically pure. Such measurements also show that the Eu atom in Eu(tfc)3 preferentially complexes with the amide carbonyl. Similar optishift pmr studies on model quinoxaline‐dipeptide esters reveal that the amino‐terminal α‐amino acid suffers appreciable racemization during the coupling process with triphenylphosphite‐pyridine, whereas no detectable racemization is observed with diphenylphosphoryl azide. A Bystrov's model is suggested for the quinoxaline‐dipeptide‐Eu complexes studied. The benzylic protons of phenylalanine and the isopropyl methyls in their quinoxaline derivatives show signal splitting due to diastereotopy in the presence of Eu(tfc)3.
2‐Aminothiazole derivatives. I. Mass spectra of 2‐acetylacetamidothiazoles and N‐(2‐thiazolyl)‐β‐(2′‐thiazolylamino)crotonamides
Authors: Saint‐Ruf G. , Silou Th.
Published: April 2009

2‐Acetylacetamidothiazoles (2) and N‐(2‐thiazolyl)‐β‐(2′‐thiazolylamino)crotonamides (3) break down in a well‐defined manner upon electron impact. In either of the two cases, the fragmentation pattern involves hydrogen transfer, similar to the McLafferty rearrangement. The principal ions formed are characterised and the most plausible mechanism of their formation is discussed.
Heteroaromatic boron compounds. XV. Deuteriodeprotonation in some borazarothienopyridines and thienopyridines
Authors: Gronowitz Salo , Roos Curt , Sandberg Elina , Clementi Sergio
Published: April 2009

Deuteriodeprotonation of some substituted 4,5‐borazarothieno[2,3‐c]pyridines (I) and 7,6‐borazarothieno[3,2‐c]pyridines (II) has been studied by the nmr technique. Exchange occurred predominantly in the 3‐position, and the effect of methyl substitution on rate is discussed. The rates of exchange in some derivatives of I and II were compared with those of the isoelectronic thieno[2,3‐c]pyridines (III) and thieno[3,2‐c]pyridines (IV). Similar rates were obtained, confirming the aromatic nature of I and II. The deuteriodeprotonation of 4‐methyl‐4,5‐borazaro‐thieno[2,3‐c]pyridine (Ie), 7‐methyl‐7,6‐borazarothieno[3,2‐c]pyridine (IIe), 4‐methylthieno‐[2,3‐c]pyridine (IIIe), and 7‐methylthieno[3,2‐c]pyridine (IVe) were measured at different concentrations of deuteriosulfuric acid and different temperatures, showing that the protonated heterocycles are substrates in the deuteriodeprotonation reaction. Standard rates at p0 H and 100° were calculated for these systems.
An investigation of oxidative animation of 2‐methyl‐1,4‐benzoquinone with pyrrolidine
Authors: Shaikh Yunus A.
Published: April 2009

Oxidative amination of 2‐methyl‐1,4‐benzoquinone with pyrrolidine yielded 2‐methyl‐6‐pyrrolidino‐1,4‐benzoquinone as the major product along with 2‐methyl‐5‐pyrrolidino‐1,4‐benzoquinone formed as the minor product. No detectable amount of 2‐methyl‐3,6‐bis‐(pyrrolidino)‐1,4‐benzoquinone was observed.
Pyrazolones and quinoxalines from 4‐phenyl‐2,3‐dioxobutyro‐1,4‐lactone
Authors: Mokhtar H. M. , El‐Shafei Z. M. , El Khadem H. S. , Swartz D. L.
Published: April 2009

4‐Phenyl‐2,3‐dioxobutyro‐1,4‐lactone (1) gave with phenylhydrazine and ils p‐Cl, p‐Br, p‐I and p‐NO2 derivatives, bishydrazones which were eyclized to 1‐aryl‐3‐(α‐hydroxybenzyl)‐4,5‐dione‐4‐arylhydrazones. With o‐phenylene diamine, compound 1 gave either a Schiff base or a substituted quinoxaline, depending upon the ratio of the reactants.
Synthesis of a pyrano[2,3‐b] pyridine with vinylogous hydroxamic acid structures
Authors: Löwe Werner
Published: April 2009

A new, two step synthesis of a pyrano[2,3‐b]pyridine derivative 5 is described. Dehydro‐acetic acid and N,N‐dimethylformamide dimethylacetal was condensed to form 2. Compound 2 was converted into 5 by reaction with hydroxylamine which opens the lactone ring.
Evidence for an indirect halogen exchange in the reaction of trans‐ 2,3‐dibromo‐2,3‐dihydrobenzofuran with chloride ions
Authors: Baciocchi Enrico , Clementi Sergio , Ruzziconi Renzo , Sebastiani Giovanni V.
Published: April 2009

Treatment of the title compound with chloride ions in acetonitrile leads mainly to the formation of trans‐2,3‐dichloro‐2,3‐dihydrobenzofuran. Since a nucleophilic displacement of bromide anion by chloride anion can be excluded, a mechanism involving the equilibrium 2Cl− + Br2 ⇋ 2Br− + Cl2 is suggested.
Photodimerization of 3‐methyl‐4‐nitro‐5‐styrylisoxazole in the solid state
Authors: Donati D. , Fiorenza M. , Moschi E. , Sarti‐Fantoni P.
Published: April 2009

The photoreactivity of 3‐methyl‐4‐nitro‐5‐styrylisoxazole in the solid state was studied and the centrosymmetric product identified.
Chloration et S‐oxydation du benzo[b]thiophène par l'hypochlorite de tertiobutyle. Mécanisme de la réaction
Authors: Geneste Patrick , Olivé Jean‐Louis , Ung Sak Neng
Published: April 2009

Dans la réaction avec le benzothiophène, l'hypochlorite de tertiobutyle intervient comme réactif d'oxydation et de chloration: c'est en effet une source d'acide hypochloreux et de chlore. L'é'tape primaire de la réaction est une S‐oxydation conduisant au sulfoxyde du benzothiophène qui réagit trAès rapidement avec le chlore formé pour donner des composés d'addition. Le passage intermédiare par le benzothiophène 1‐oxyde a eté mis èn evidence par la technique du flux stoppé en spectroscopic uv. J. Heterocyclic Chem., 14, 953 (1977).
The synthesis of l‐alkyl‐2‐benzoyl‐4‐methylazetidine. Configurational and conformational studies
Authors: Kulkarni Shrikant B. , Cromwell Norman H.
Published: April 2009

α,γ‐Dibromovalerophenone (3) reacted with primary amines to give a number of l‐alkyl‐2‐benzoyl‐4‐methylazetidines (4) in good yield. The results of the base catalyzed reactions performed on these new carboazetidines imply that the cis isomer is of greater thermodynamic stability. Furthermore, base catalyzed deuterium exchange studies suggest this to be the case. J. Heterocyclic Chem., 14, 981 (1977)
Studies on the chemistry of 2,3,5,6‐tetrahydro‐6‐phenylimidazo[2,l‐b]‐thiazole. III. . Reaction with isocyanates and isothiocyanates
Authors: Bigg D. C. H. , Faull A. W. , Purvis S. R.
Published: April 2009

2,3,5,6‐Tetrahydro‐b‐phenylimidazo[2,l‐b‐]thiazole reacts with aryl isothiocyanates to give dipolar 1:1 adducts. The adducts are relatively unstable and, in solution, exist in equilibrium with starting materials. The reaction with aryl and alkyl isocyanates, however, leads to cyclic 2:1 adducts, while sulphonyl and acyl isocyanates give stable dipolar 1:1 adducts. J. Chem. Soc., 14, 989 (1977)
Thermolysis of the reaction products from 2‐pyridylacetohydrazide and nitrous acid
Authors: Iwao Masatomo , Kuraishi Tsukasa
Published: April 2009

2,3‐Dihydroimidazo[1,5‐α]pyridin‐3‐one (IV) was obtained by thermolysis of 2‐pyridylacetyl azide (II) which was prepared from 2‐pyridylacetohydrazide (I) on treatment with an equivalent mole of nitrous acid. Treatment of I with excess nitrous acid yielded α‐oximino‐α:‐(2‐pyridyl)‐acetylazide (V). Thermal decomposition of V gave 3‐(2‐pyridyl)‐1,2,4‐4H‐oxadiazolin‐5‐one (VII). 2‐Cyanopyridine (IX) was obtained from V by the action of alkali. 2,3‐Dihydroimidazo‐[1,5‐α ]pyridin‐3‐one (IV) was rearranged to VII upon treatment with nitrous acid. J. Chem. Soc., 14, 993 (1977)
A facile synthesis of 2‐substituted‐4‐(substituted)phenyl‐Δ2‐1,3,4‐oxadiazolin‐5‐ones
Authors: Pilgram Kurt , Skiles Richard D.
Published: April 2009

The title compounds, 3, are formed at ambient temperature from 4,4‐dimethyl‐2‐(substituted)‐phenylsemicarbazides (1) and carboxylic acid chlorides in the presence of triethylamine. 2‐Dimethylamino‐4‐(substiluted)phenyl‐Δ2‐1,3,4‐oxadiazolin‐5‐ones are formed from 1 and dialkyl‐carbamoyl chlorides at elevated temperature (about 15° ). Acylation of 1 with carboxylic acid anhydrides, also at elevated temperature, is accompanied by loss of dimethylamine from the intermediate l‐acyl‐4,4‐dimethyl‐2‐(substituted)phenylsemicarbazides, 2, to give 3.
Synthesis of 5H[l]benzopyrano[3,4‐b]pyridin‐5‐one and its derivatives
Authors: Khan Misbahul Ain , Gemal Andre Luis
Published: April 2009

3‐Aminocoumarin undergoes the Skraup reaction to give a new ring system, 5H[l]benzo‐pyrano[3,4‐b]pyridin‐5‐one (IVa). When 3‐aminocoumarin was condensed with the ethoxy methylene derivatives of active methylene compounds, ethyl acetoacetate, and dimethyl acetylenedicarboxylate, the intermediates Vla‐VIf were formed which on thermal cyclizations afforded other derivatives of 5H[l ]benzopyrano[3,4‐b]pyridin‐5‐one (IVb‐IVf). The nitration of IVa gave IVg.
Recherches en série diazépine‐1,4 et triazépine‐1,2,4. X. Réductions et méthylations de pyrazolo[3,4‐b]diazépines‐1,4
Authors: Affane‐Nguéma J.‐P. , Lavergne J.‐P. , Viallefont Ph.
Published: April 2009

Les réductions et méthylations de pyrazolo[3,4‐b]diazepines‐1,4, selon différentes méthodes, ont été réalisées.

Selon les agents de réduction, il a été possible de réduire sAélectivement une double liaison C=N, le groupe carbonyle ou d'effectuer la rAéduction totale des cycles diazépinones, de réduire partiellement ou totalement les insaturations des (6H)pyrazolodiazépines.

La méthylation a pu ětre obtenue sur l'atome d'azote amidique, sur Patome d'oxygène de la měme fonction, dans quelques cas sur l'atome de carbone C6 des pyrazolodiazépinones et enfin sur la position 4 des tétrahydro pyrazolodiazépinones.
New syntheses of condensed heterocycles from isoxazole derivatives. V. Pyrrolo[3,4‐b ]pyridin‐4‐ones
Authors: Dattolo G. , Aiello E. , Plescia S. , Cirrincione G. , Daidone G.
Published: April 2009

Hydrogenolysis with Raney‐Nickel or iron powder in acetic acid of 2,5‐diphenyl‐4‐nitro‐3‐(3,5‐R,R‐4‐isoxazolyl)pyrrolyl ketones, prepared by the Grignard reaction of 2,5‐diphenylpyrrole and 3,5‐R,R‐4‐isoxazolecarboxilic acid chlorides followed by nitration, afforded directly the desired 6H‐pyrrolo[3,4‐b ]pyridin‐4‐ones.
Synthesis of alkyl indole derivatives
Authors: Shaikh Yunus A.
Published: April 2009

Condensation of arylamines with α‐halogenoketone afforded the intermediate anilino‐ketones which on direct cyclization furnished the corresponding alkylindoles. Synthesis of 2,3,5‐trimethyl‐4,7‐dimethoxyindole (5a) and 2,3,6‐trimethyl‐7‐methoxyindole (5b) is described. Earlier (1) synthesis of 2,3‐dimethyl‐4,7‐dimethoxyindole and 1,2,3‐trimethyl‐4,7‐dimethoxy‐indole is reported.
Pyrimido[5,4‐b]quinolines. III. Synthesis of 10‐alkyl‐substituted 10‐deazaalloxazines
Authors: Chu C. K. , Bardos T. J.
Published: April 2009

A general method for the synthesis of 10‐alkyl‐substituted 10‐deazaalloxazines (VIII) and the related chemistry are described. 4‐Alkyl‐substituted 3‐aminoquinolines (IV) were reacted with benzoyl chloride and potassium cyanide in methylene chloride‐water mixture to obtain Reissert compounds (V) which were hydrolyzed with a mixture of hydrobromic acid and acetic acid, and subsequently with 20% potassium hydroxide to give the corresponding 3‐aminoquinaldic acids (VII). Cyclization with urea gave the 10‐deazaalloxazines (VIII). Oxidation, hydroxylation and alkylation reactions of the 10‐methyl derivatives (VIIIa,b) and of their quinaldic acid precursors are also reported.
Chemistry of the phenoxathiins i. Synthesis of 1‐azaphenoxathiin analogs as potential new CNS depressant agents
Authors: Martin G. E. , Turley J. C. , Williams L. , Steenberg M. L. , Buckley J. P.
Published: April 2009

The condensation of the disodium salt of 2‐mercapto‐3‐pyridinol with various ortho‐nitrohalo‐benzenes to yield a group of previously unreported 1‐azaphenoxathiins is described. The synthetic pathway and the substituent location on the products is unequivocably demonstrated by Fourier Transform1 3 C‐nmr. Preliminary pharmacologic evaluation of the title compounds as potential CNS depressant agents is also reported.
Synthesis of some new 3‐pyrazolyl‐substituted‐4(3H)quinazolinones
Authors: Plescia Salvatore , Daidone Giuseppe , Dattolo Gaetano , Aiello Enrico
Published: April 2009

N‐(1‐Phenyl‐3‐methylpyrazol‐5‐yl)‐o‐aminobenzamide reacted with orthoesters to yield some new 3‐pyrazolyl‐substituted‐4(3H)quinazolinones (VIIa,b,c,d). An alternative synthesis of Vllb was accomplished by reaction of acetylanthranyl with l‐phenyl‐3‐methyl‐5‐aminopyrazole.
A convenient synthesis of 2‐aminopyridine‐3‐carbonitriies
Authors: Kurihara Hideshi , Mishima Hiroshi
Published: April 2009

The 5‐ and/or 6‐alkyl substituted derivatives of 2‐aminopyridine‐3‐carbonitrile were synthesized via dienamine intermediates (3) produced by the addition‐elimination reaction of various enamines to methoxymethylene malondinitrile. The reaction can be carried out without the isolation of the dienamine intermediates.
A malonic ester‐type synthesis with 4‐chloroquinoline utilizing highly acidic enols
Authors: Scoville Ann , Smith Francis X.
Published: April 2009

A synthetic method of attaching carbon‐chain substituents to the 4‐position of the quinoline ring was developed. In our approach enolate anions were generated from highly acidic enols under conditions in which the 4‐chloroquinoline can be N‐acylated or N‐protonated. Isopropylidene alkyl(4‐quinolyl)malonates or 5‐alkyl‐5‐(4‐quinolyl)barbituric acids were obtained from the reaction of 4‐chloroquinolines with isopropylidene alkylmalonates in acetic anhydride or with 5‐alkylbarbituric acids by heating in the absence of solvent. Some of the products were hy‐drolyzed and decarboxylated to give the corresponding 4‐alkylated quinolines.
The reaction of aroylhydrazines with N‐phenylsulfonylarenehydrazonoyl chlorides. A route to substituted 4‐amino‐(4H)‐1,2,4‐triazoles and 1,3,4‐oxadiazoles
Authors: Shawali Ahmad S. , Fahmi Abdel‐Gawad A.
Published: April 2009

Treatment of N‐phenylsulfonylarenehydrazonoyl chlorides (II) with equivalent amounts of aroylhydrazines (III) in ethanol gave 3,5‐diaryl‐4‐phenylsulfonylamino‐1,2,4‐triazoles (IV). Reaction of II with two equivalents of III in tetrahydrofuran gave 2,5‐diaryl‐1,3,4‐oxadiazoles (V), in addition to IV. Addition of triethylamine to II or its mixture with III yielded only the tetrazenes (VIII). The possible pathways leading to IV‐V and VIII are discussed. J. Chem. Soc., 14, 1089 (1977)
A new facile synthesis of 5‐arninopyridazine‐4‐carboxylic acid
Authors: Chimichi S. , Nesi R.
Published: April 2009

Hofmann rearrangement of 5‐carbamylpyridazine‐4‐carboxylic acid (6), obtained from pyrida‐zine‐4,5‐dicarboxylic acid (3) through the corresponding anhydride (5), afforded 5‐aminopyrida‐zine‐4‐carboxylic acid (1) in good yield. Compound 1 cyclised with benzoyl chloride in pyridine to give 2‐phenylpyridazino[4,5‐d]‐1,3‐oxazin‐4‐one (7), a new heterocyclic ring system. J. Heterocyclic Chem., 14, 1099 (1977)
Structure of azomesobilirubin isomers
Authors: Salmon Manuel
Published: April 2009

The structure of azomesobilirubin isomers as their methyl esters were determined using nmr and Eu(fod)3 as a shift reagent. J. Chem. Soc., 14, 1101 (1977)
Synthesis of 3‐methyl‐[1,2,4] ‐triazepino[6,5,4‐jk] carbazol‐4(3H)one
Authors: Peet Norton P. , Sunder Shyam
Published: April 2009

The title compound (14), a representative of a novel ring system, was prepared from 9H‐carbazole‐1‐carboxylic acid 1‐methylhydrazide (7) and triethyl orthoformate. Attempted cyclization of 7 with triethyl orthoacetate led only to 9H‐carbazole‐l‐carboxylic acid 2‐(l‐ethoxyethylidene)‐l‐methylhydrazide (16). Treatment of 16 with trifluoroacetic acid gave 9H‐carbazole‐1‐carboxylic acid (12). A postulated mechanism for this transformation was supported by studies with model compounds. A new synthesis of 1‐benzoyl‐2‐methylhydrazine (24), using 1‐acetyl‐1‐methylhydrazine (22) as a synthon, is described.
Quinazolines and 1,4‐benzodiazepines LXXIX. 8‐nitro‐pyrazolo[1,5‐a]‐[1,4] benzodiazepines
Authors: Gilman Norman W. , Fryer R. Ian
Published: April 2009

The preparation of 8‐nitro substituted pyrazolobenzodiazepines from 2‐fluoro‐5‐nitrobenzo‐phenone (1) and 3,5‐diacetoxymethylpyrazole (2) is reported.
Comparison between triplet and singlet molecular oxygen oxidation of fully substituted alkoxyoxazoles
Authors: Graziano M. L. , Carotenuto A. T. , Iesce M. R. , Scarpati R.
Published: April 2009

Oxidation by ground‐state molecular oxygen of fully substituted alkoxyoxazoles I gave imines IV as major products; diacylcarbamates III were also obtained as minor products. The free radical nature of the autoxidation was established. A mechanistic interpretation of the results is suggested also in the light of the results of the oxidation with singlet oxygen.
3‐Azido‐1,2,4‐triazine N‐Oxides. Syntheses and structure elucidation
Authors: Goodman Mark M. , Paudler William W.
Published: April 2009

Several 3‐azido‐1,2,4‐triazine 1‐oxides were prepared by treating the appropriate 3‐hy‐drazino derivatives with nitrous acid. 3‐Azido‐1,2,4‐triazine 2‐oxide was prepared by reaching the corresponding 3‐bromo derivative with either tetramethylguanidinium azide in chloroform or sodium azide in aqueous acetone. The azido derivatives which could cyclize to form the tetra‐zolo isomers were proven to exist enitrely in the open chain form by a 13C nmr, 1H nmr and infrared spectroscopic study.
Central nervous system depressants. 14. As‐triazino‐1,4‐benzodiazepines
Authors: Moffett Robert Bruce , Evenson Gerald N. , Von Voigtlander P. F.
Published: April 2009

Seven series of as‐triazino[4,3‐a] [1,4]benzodiazepines were prepared which differed in the degree of unsaturation or the nature and position of oxygen function on the triazino ring. These were prepared by closing the triazino ring of appropriately substituted hydrazones from 2‐hydrazinobenzodiazepines or by condensing substituted hydrazines with 2‐thiobenzodiazepines. Most of these represent new ring systems. They were tested in a battery of tests designed to uncover central nervous system activities. Most of the activity was found in tests thought to be indicative of anxiolytic, hypnotic or sedative potential. Five of the series contained members more active than the standard, diazepam, and a few of the compounds were among the most potent benzodiazepines known. Some of the intermediate benzodiazepine hydrazones were also active.
Reactions of methylpyrylium, thiapyrylium, and flavylium salts with tetracyanoethylene
Authors: Haley N. F.
Published: April 2009

The reaction of 2‐ or 4‐methyl‐2,6‐diphenylpyrylium perchlorate with tetracyanoethylene (TCNE) in pyridine gives 2‐ or 4‐(2,3,3‐tricyanopropylidene)‐2,6‐diphenylpyran in good yield. Similar results are obtained from 2‐ or 4‐methyl‐2,6‐diphenylthiapyrylium and 4‐methylflavylium perchlorates. In one case a stable charge‐transfer salt is isolated from the reaction of a methylene base and TCNE. The reaction mechanism of dye formation is discussed.
Chemistry of the phenoxathiins II. Synthesis of 1‐azaphenoxathiin
Authors: Martin G. E. , Turley J. C. , Williams L.
Published: April 2009

The synthesis of 1‐azaphenoxathiin, the parent ring system of a recently reported class of novel CNS agents is described. The 13C‐nmr spectrum and its assignment are also reported as a model for structure confirmation studies.
Synthesis of 1,5‐dideazariboflavin
Authors: Weinstock Louis T. , Wiegand C. J. Wesley , Cheng C. C.
Published: April 2009

1,5‐Dideazariboflavin, an analog of riboflavin containing the original conjugated double bond system between positions 1 and 5, was synthesized by the condensation of 4,5‐dimethyl‐ N‐ribitylanthranilaldehyde and the sodium salt of 2,4,6‐piperidinetrione.
Synthesis of 9‐oxo‐15‐hydroxy‐8‐azaprost‐13‐ene
Authors: Zoretic P. A. , Soja P.
Published: April 2009

The synthesis of a prostaglandin analog 9‐oxo‐15‐hydroxy‐8‐azaprost‐13‐ene is reported.
Synthèse d'hydroxyspirocétals insaturés et hétérocyclisation en méthyl‐5 trioxa‐2,6,11 tricyclo[5.3.1.01.5]undécane
Authors: Cottier Louis , Descotes Gérard
Published: April 2009

L'irradiation photochimique de cétoacétals insaturés 4 conduit à des hydroxyspirocétals insaturés isomères 6 qui évoluent par hétérocyclisation en polyéther tricyclique de type 7.
Alkylation de la dimethyl‐5 5′ isoxazolidinone‐3 en catalyse par transfert de phase
Authors: Ly Bunkuoy , Dou Henri J. M. , Hassanaly Mme Parina , Verducci Jean
Published: April 2009

L'alkylation en catalyse par transfert de phase d'anions ambidents du type N‐C‐O− conduit à un mélange de composés O et N substitués. Les pourcentages de O substitution sont de Fordre de 20% avec des halogénures primaires, et de 35% avec des halogénures secondaires. Le rendement total de la réaction est de 60% en moyenne.
Synthesis of 7‐oxo‐8‐aza‐10a‐homoprost‐13‐enoic acid
Authors: Zoretic Phillip A. , Shiah T.
Published: April 2009

The synthesis of a prostaglandin E1 analog, 7‐oxo‐8‐aza‐10a‐homoprost‐13‐enoic acid, is reported.
Etude de l'équilibre azido ⇌ tétrazole dans la séric du thiazolo[2,3‐e]‐tétrazole. III. Effects des substituants
Authors: Faure Robert , Galy Jean‐Pierre , Vincent Emile‐Jean , Elguero José
Published: April 2009

Les effets de substituant sur l'équilibre azido/tétrazole ont été étudiés par résonance magnétique du proton dans deux solvants deutériés (chloroforme et diméthylsulfoxyde) dans le cas des azidothiazoles, benzothiazoles, thiadiazoles et isoxazoles. Pour les dérivés du thiazole, on trouve une excellente relation de Hammett, aussi bien pour les substituants en position 4 qu'en position 5.
Nucléosides de synthèse XIV. Du choix des paramètres réactionnels pour l'obtention préférentielle de nucleosides en série benzoazole par réaction de fusion
Authors: Barascut Jean‐Louis , Kam Bernard L. , Imbach Jean‐Louis
Published: April 2009

Grǎce au choix de certains paramétres réactionnels, de la réaction de (usion acido‐catalysée, notamment du pourcentage de catalyseur, nous avons synthétisé divers nucléosides des séries benzotriazole et benzimidazole. Cette approche nous a permis d'obtenir pour la première fois les nucléosides N‐2 substitués ainsi que les anomères α substitutés en N‐1 correspondant à ces aglycones. Nous avons ainsi montré qu'il était possible d'augmenter la sélectivité de la réaction de fusion acido‐catalysée.
Synthesis of the thia‐analog of angustidine, angustoline, naucléfine and nauéletine
Authors: Shafiee A. , Rashidbaigi A.
Published: April 2009

Condensation of 1‐methyl‐3,4‐dihydrobenzo[b]thieno[2,3‐c]pyridine (6) with nicotinic acid in the presence of ynamine (12) gave 2‐nicotinyl‐1,2,3,4‐tetrahydro‐1‐methylenebenzo[6]thicno‐|2,3‐c]pyridine (13). Photocyclization of the enamide (13) afforded thia‐analog of naueléfine (15). Thia‐analogs of angustidine (19), and nauclétine (27) were prepared similary through photocyclization of the enamides 18 and 26, respectively. Reduction of 27 with sodium boro‐hydride gave thia‐analog of angustoline (29).
Catalysis in aromatic nucleophilic substitution. Note II. Piperidino substitution reactions of some 2‐l‐3‐nitrothiophenes and 2‐l‐5‐nitrothiophenes in methanol and benzene
Authors: Spinelli Domenico , Consiglio Giovanni , Noto Renato
Published: April 2009

The rates of piperidino substitution of some 2‐L‐3‐nitrothiophenes (I) and 2‐L‐5‐nitrothiophenes (II) (L = Cl, Br, I, OC6H4NO2‐p, and SO2Ph) have been measured in methanol and in benzene at various piperidine concentrations. The reactivity of compounds (I) is not affected by the piperidine concentration in both methanol and benzene, except for the case of L = I (Ic). Probably due to association effects, the reactivity of Ic in benzene decreases as the piperidine concentration is increased. The reactions of compounds II follow overall second order kinetics in methanol while in benzene a different behaviour is observed as a function of the nature of the leaving group. In fact, the piperidino substitutions of IIa‐c (L = Cl, Br, I) are mildly accelerated at high piperidine concentrations (a moderate solvent effect); on the contrary the reactivity of IId and e shows a strong dependence on the piperidine concentration, pointing out a genuine base catalysis.
Studies on the synthesis of heterocyclic compounds. III. Synthesis of 1,3,2‐benzodioxa‐ and 1,3,2‐benzoxathiarsole derivatives
Authors: Anchisi Carlo , Corda Luciana , Maccioni Antonio , Podda Gianni , Cabiddu Salvatore
Published: April 2009

The preparation and reaction of 1,3,2‐benzodioxa‐ and 1,3,2‐benzoxathiarsoles (IIa‐b) are described. Spiran derivatives Va‐c are obtained by treating IIa‐b with Ia‐b and triethylamine, while the reaction of IIa‐b with sodium hydroxide, ethoxide and p‐cresolate gives the compounds VIa‐b, VIIa‐b and VIIIa‐b, that can evolve to Xa‐b. Reaction of IIa‐b with sodium p‐toluenethio‐late and n‐butyllithium gave the compounds IXa‐b and XIa‐b respectively. The structure of the prepared compounds has been determined by elemental analysis and spectroscopic data.
A PMR conformational study of some (E)‐α‐nitro‐β‐arylstyrenes
Authors: Arcoria A. , Bottino F. A. , Sciotto D.
Published: April 2009

The 60 MHz room temperature pmr data of some α‐nitro‐β‐arylstyrenes are used to assign the stereochemical configuration. The variable temperature pmr spectra exclude the presence of a rotational isomerism. The preferred conformation are then established by analysis of the chemical shifts of the heterocyclic protons.
The oxidative coupling of indole with some phenolic compounds, naphthols and catechols
Authors: Omote Yoshimori , Takizawa Yasuomi , Mochida Shunichi , Tsuda Yoshihiko , Sugiyama Noboru
Published: April 2009

The oxidative coupling of indole with three naphthols, 2‐naphthol, 2,3‐dihydroxynaphthalene and 2,7‐dihydroxynaphthalene gave 1,1‐bis(3′‐indolyl)‐2(1H)naphthalenone, 1,1‐bis(3′‐indolyl)‐3‐hydroxy‐2(1H)naphthalenone and 1,1‐bis(3′‐indolyl)‐7‐hydroxy‐2(1H)naphthalenone, respectively. The coupling of indole with protocatechuic aldehyde gave bis‐(3‐indolyl)‐(3′,4′‐di‐hydroxyphenyl)methane and that of indole with homocatechol gave 3‐(2′‐methyl‐3′,4′‐di‐hydroxyphenyl)indole.
Pseudo‐phenalenone und pseudophenaleniumsalze sowie ihre reaktionen
Authors: Neidlein R. , Kraemer A. D.
Published: April 2009

The reactivity of the thiapseudophenalenone (1, 2‐phenyl‐5H‐naphtho[1,8‐bc]thiophen‐5‐one) and of the thiapseudophenalenium salt (2, 2‐phenyl‐5‐ethoxynaphtho[1,8‐bc]thioliumtetra‐fluoroborate) towards N‐nucleophilic compounds R‐NH2 was of interest. We obtained the substituted iminothiapseudophenalenones (3a‐3i, 4). With C‐nucleophilic reactants we isolated 4a, 4b, 8‐11 and with 2,3,4,5‐tetrachlorocyclopentadiene we obtained thiapentapseudophena‐fulvalene (7).
The reaction of 2,6‐diphenyl‐2,3,5,6‐tetrahydro‐4H‐thiopyran‐4‐one with sulfuryl chloride
Authors: Van Allan J. A. , Reynolds G. A. , Chen C. H.
Published: April 2009

2,6‐Diphenyl‐2,3,5,6‐tetrahydro‐4H‐thiopyran‐4‐one was treated with one, two, and three equivalents of sulfuryl chloride in the presence of pyridine to give the dihydrothiopyranone 2, the 3‐chlorodihydrothiopyranone 3, and the triehlorotetrahydrothiopyranone 4, respectively. Compound 4 was converted to 3‐chloro‐2,6‐diphenyl‐4H‐thiopyran‐4‐one by pyrolysis and to 3‐hydroxy‐2,6‐diphenyl‐4H‐thiopyran‐4‐one on treatment with alcohols. Several pyrylium dyes were prepared from the latter compounds.
Three convenient and novel syntheses of 4‐amino‐2‐arylpyrimidines
Authors: Singh Baldev , Lesher George Y.
Published: April 2009

4‐Amino‐2‐arylpyrimidines can be prepared conveniently by the reaction of an amidine with the readily available 3‐ethoxyacrylonitrile, 2‐chloroacrylonitrile or 2‐(1‐piperidinyl‐methyl)acrylonitrile.
Diels‐alder reactions of pyrroles as an entry to substituted 3‐oxatropanes and tetrasubstituted pyrrolidines
Authors: Donnini C. Paul , Just George
Published: April 2009

The Diels‐Alder adduct of N‐(p‐toluenesulfonamido)pyrrole and dimethyl acetylenedi‐carboxylate, 2,3‐dimethyl N‐(p‐toluenesulfonamido)‐7‐azabieyclo[2.2.1]‐2,5‐heptadiene‐2,3‐di‐carboxylate (1c), was obtained in good yield and converted to remarkably stable 3‐oxatropanes (6 and 8) in 25% yield.
Synthesis of pyridyloxadiazoles 1. Characterization and thermal rearrangement of an unexpected 1,2,4‐oxadiazol‐5(4H)one
Authors: Marquez Victor E. , Diparsia Maria T. , Kelley James A.
Published: April 2009

The synthesis of pyridyloxadiazoles by the reaction of acid chlorides with 5‐(2‐pyrklyl)‐tetrazole or 2‐pyridineamidoxime was studied. Reaction of 2‐pyridineamidoxime with N,N‐dimethylcarbamyl chloride produced 3‐(2‐pyridyl)‐4‐N,N‐dimethylaminocarbony 1‐1,2,4‐oxadi‐azol‐5(4H)one instead of the expected oxadiazole. The oxadiazolone underwent thermal rearrangement with expulsion of carbon dioxide to yield the desired 3‐(2‐pyridyl)‐5‐N,N‐dimethylamino‐1,2,4‐oxadiazole.
Reactivity of the A‐CH=N‐NR‐CX‐B system. 4‐R‐5‐hydroxy‐5‐phenyl‐2,3,4,5‐letrahydro‐1,2,4‐triazine‐3‐thiones
Authors: Werber Giuseppe , Buccheri Francesco , Vivona Nicolb , Gentile Manila
Published: April 2009

The behaviour of phenylglyoxal thiosemicarbazones towards aqueous sodium hydroxide have been studied. Examples of addition compounds, 5‐hydroxy‐5‐phenyl‐2,3,4,5‐tetrahydro‐1,2,4‐triazine‐3‐thiones, are reported.
The synthesis of 2‐phenyl‐5H‐imidazo[2,1‐a] [2,4]benzodiazepines
Authors: Fryer R. Ian , Earley James V.
Published: April 2009

A one step synthesis of 2‐phenyl‐5H‐irnidazo[2,1‐a][2,4]benzodiazepines (4) from 2‐(2‐imidazolyl)benzophenones (3) is reported. Oximation and reduction of the benzophenone, 3a led to the benzhydrylamine derivative 7 which was cyclized to differently substituted 6,7‐di‐hydroimidazo[2,1‐a][2,4]benzodiazepines depending on the reactant chosen.
Quaternary salts from 2‐(methylpyridyl or quinolyl)benz‐X‐azoles and related polymethine dyes
Authors: Barni Ermanno , Savarino Piero
Published: April 2009

The quaternisation of 2‐(methylpyridyl or quinolyl)benz‐X‐azoles mainly leads to the corresponding pyridinium and quinolinium salts, from which polymethine dyes are prepared. The electronic spectra and the methyl protons chemical shifts are briefly discussed.
Stéroidohétérocycles: Hétérocycles azotés a 5,6 et 7 chainons accolés simultanément aux cycles A et B d'un stéroide par les positions 4,5 et 6
Authors: Daunis Jacques , Del Vecchio Gérard , Jacquier Robert , Lopez Hélène , Maury Georges
Published: April 2009

De nouveaux systèmes formés d'un hétérocycle azoté à cinq, six ou sept chaînons (pyrazole, pyrimidine ou diazépine) accolé simultanément aux deux cycles A et B d'un dérivé du cholestane par les positions 4, 5 et 6 ont été préparés.
Synthesis of 6‐chlorofuro[2,3‐b]pyridine‐2‐carboxylie acid
Authors: Weis C. D.
Published: April 2009

A new route was employed to synthesize methyl 6‐ehlorofuro[2,8‐b]pyridine‐2‐earboxylate by eoneurrent dehydrohalogenation and dehydration of 3‐ehloro‐3‐(β,β‐dichloro‐β‐ethoxycar‐bonylelhyl)‐2,6‐piperidinedione using methyl phosphonyl chloride.
Unimolecular reaction sequence in the electron impact induced fragmentation of some methylenoxazolidinones
Authors: Giannetto Placido , Sindona Giovanni , Uccella Nicola
Published: April 2009

The unimolecular processes of some methylenoxazolidinones bombarded in the gas phase by electrons have been investigated by MIKE analysis, precise mass measurements and isotopic labelling studies. The overall delocalisation effect of the substitution on the nitrogen contained has been ascertained through the study of the reaction mechanism and of the possible reacting ionic structures.