bluuebunny/crossref_metadata_2025_split huggingface dataset:
The synthesis of a 12,13‐dihydro‐5H‐dibenzo[b,g] [1,5] diazonine by a novel ring enlargement reaction
Authors: Aeberli Paul , Houlihan William 
Published: April 2009

AbstractA novel method for ring expansion of a heterocycle containing a NCN system to a medium sized diaza‐heterocycle has been demonstrated for the conversion of an isoindolo[2,1‐a]‐quinazoline derivative 8 to the 5H‐dibenzo [b,g] [1,5]diazonine (13). Attempts to apply this isomerization to heterocyclic systems related to 8 were not successful.
Reaction of diethyl (phthalimidoacetyl)malonate with hydroxylamine
Authors: Bregant N. , Perina I. 
Published: April 2009

AbstractThe reaction of diethyl (phthalimidoacetyl)malonate with hydroxylamine was investigated. Depending upon the reaction conditions, N‐phthaloylglycinehydroxamic acid (2) and the cyclized product, 4‐ethoxycarbonyl‐5‐hydroxy‐3‐(phthalimidomethyl)isoxazole (4), were obtained.
4‐Substituted‐3‐alkyl‐3,4‐dihydro‐2H‐1,3‐benzoxazin‐2‐ones II (1,2). Solvolytic transformations of urea and thiourea derivatives into 1‐alkyldihydro‐6‐(2‐hydroxyaryl)‐1,3,5‐triazine‐2,4‐(1H,3H) diones
Authors: Bobowski George , Shavel John 
Published: April 2009

AbstractA series of 3,4‐Dihydro‐2‐oxo‐(3‐substituted‐2H‐1,3‐benzoxazin‐4‐yl)ureas (II, Table I) and 3,4‐dihydro‐2‐oxo‐(3‐substituted‐2H‐1,3‐benzoxazin‐4‐yl)thioureas (Table II) was prepared by treating 3,4‐dihydro‐4‐hydroxy‐3‐substituted‐2H‐1,3‐benzoxazin‐2‐ones with ureas and thioureas, respectively. In the presence of alcoholic alkali these compounds underwent transacylation to dihydro‐6‐(2‐hydroxyaryl)‐1,3,5‐triazine‐2,4‐(1H,2H)diones (Table III) and their 4‐thio analogues (Table IV).
The decarbonylation reaction of imidazole‐2‐carbaldehydes in ethanol
Authors: Antonini Ippolito , Cristalli Gloria , Franchetti Palmarisa , Grifantini Mario , Gulini Ugo , Martelli Sante 
Published: April 2009

AbstractImidazole‐2‐carbaldehydes in hot ethanol undergo a decarbonylation reaction involving nucleophilic attack of the alcohol on the carbonyl to form the corresponding imidazole and ethyl formate.
Intermediates in the reaction of singlet oxygen with trisubstituted oxazoles
Authors: Graziano M. L. , Iesce M. R. , Scarpati R. 
Published: April 2009

AbstractTrisubstituted oxazoles I react at −15° with singlet oxygen to give dioxazoles III and iminoanhydrides V which rearrange at room temperature to triamides VI. The intermediate ratio (III/V) is sensitive to the reaction temperature. It is likely that at room temperature triamides VI are essentially formed via imino‐anhydrides V.
Synthesis of 2[(4,6‐diphenyl‐2H‐pyran‐2‐ylidene)methyl]‐4,6‐diphenylpyrylium perchlorate
Authors: Reynolds G. A. , Van Allan J. A. 
Published: April 2009

AbstractThe title compound was prepared by the condensation of 4,6‐diphenyl‐2H‐pyran‐2‐one and acetophenone in phosphorus oxychloride. The absorption spectrum of this 2,2‐methine dye is compared with those of the corresponding 2,4‐ and 4,4‐methine dyes.
New benz[g]indole and spiroketone heterocycles from acyl thioacetamides
Authors: Marten E. Hoffmeister , Maggiulli C. A. 
Published: April 2009

AbstractThe acyl thioacetanilide 3 condensed with 2‐bromotetralone to give the spiroketone 5. A similar reaction of the tetralone with the acyl‐N‐ethylthioacetamide 4 afforded small amounts of the unsaturated spiroketone 6 with the isomeric dihydrobenz[g]indole 7 as the major product. Compound 7 was aromatized to the benz[g]indole 8 in high yield.
Aziridinyl ketones. XVIII. The rearrangement‐dehydrogenation of cis‐1‐cyclohexyl‐2‐phenyl‐3‐aroylaziridines
Authors: Tarburton Philip , Wall D. K. , Cromwell Norman H. 
Published: April 2009

AbstractThe sequential nature of the unique rearrangement‐dehydrogenation of cis‐1‐alkyl‐2‐aryl‐3‐aroylaziridines (1a‐d) into 2‐alkylamino‐3‐arylindenones (2a‐d) when treated with a lithium amide has been established. Furthermore, a competitive degradation pathway has been discovered which leads to ω‐aminoacetophenones and benzaldehyde, thereby accounting for the major product of this reaction. trans‐1‐Alkyl‐2‐aryl‐3‐aroylaziridines do not react with the lithium amides employed in these studies. Although 1‐cyclohexyl‐2‐methyl‐3‐benzoylaziridine reacts with lithium amide to produce a 3‐carbanion, neither a rearrangement‐dehydrogenation to a 2‐aminoindenone nor a more extensive degradation involving carbon‐carbon bond cleavage is observed. Mechanistic pathways for these base catalyzed reactions are discussed.
Studies on the synthesis of heterocyclic compounds. Part I. The pschorr reaction in the pyrazole series
Authors: Plescia S. , Daidone G. , Sprio V. , Aiello E. , Dattolo G. , Cirrincione G. 
Published: April 2009

AbstractPreparation and structural evidence of N‐methyl‐(1,3‐R,R'‐pyrazol‐5‐yl)‐o‐nitrobenzamides (VIIIa, b) are discussed. Diazotisation of related o‐aminobenzamides XIa,b followed by the Pschorr reaction afforded a very complex mixture from which pyrazolo[3,4‐c]isoquinolin‐5‐ones XIIa.b in 7–10% yields together with N‐methyl‐(1,3‐R,R'‐pyrazol‐5‐yl)‐o‐hydroxybenzamides (XIIIa) in 15–20% yields were isolated.
Five‐Membered Heterocyclic Thiones. Part VII . 1,2,3‐ThiadiazoIe‐5‐thiolates
Authors: Demaree Patricia , Doria Marie‐Carmen , Muchowski Joseph M. 
Published: April 2009

AbstractThe synthesis of the stable potassium salts of the first known 1,2,3‐thiadiazole‐5‐thiols is described.
Isothiazoles XI. Diels‐alder adducts of 4‐isothiazolin‐3‐one 1‐oxides and 1,1‐dioxides
Authors: Weiler Ernest D. , Brennan John J. 
Published: April 2009

Abstract4‐Isothiazolin‐3‐one 1‐oxides and 1,1‐dioxides react with a variety of cyclic and acyclic dienes to afford cycloaddition products.
Synthesis of 4,5‐dihydro‐4‐methyl‐1‐phenyl‐1,4,5‐benzotriazocine‐2,3,6(1H) triones
Authors: Daniel John K. , Peet Norton P. 
Published: April 2009

AbstractThe title compounds, 7a and its 9‐chloro analog 7b, were prepared in three steps from methyl N‐phenylanthranilates. Thus, methyl N‐phenylanthranilate (3a) was treated with oxalyl chloride to yield 2‐[(2‐chloro‐1, 2‐dioxoethyl) phenylamino]benzoic acid methyl ester (4a). Treatment of 4a with methylhydrazine gave 2‐([2‐(1‐methylhydrazino)‐1,2‐dioxoethyl]phenylamino) benzoic acid methyl ester (6a), which was cyclized with sodium hydride in dimethylformamide to produce 7a. Alkylation of 7a and 7b with iodomethane afforded the respective 5‐methyl derivatives 8a and 8b. A survey of the known literature benzotriazocines is presented.
Reactions of simple phospholes with dimethyl acetylenediearboxylate
Authors: Holah David G. , Hughes Alan N. , Kleemola Daniel 
Published: April 2009

AbstractReactions of the three phospholes 1‐phenylphosphole, 3‐methyl‐1‐phenylphosphole and 3,4‐dimethyl‐1‐phenylphosphole with dimethyl acetylenedicarboxylate are reported. All three phospholes react extremely readily with the acetylenic ester to give ring‐expanded bicyclic ylidic systems, although 1‐phenylphosphole appears to react by a different pathway from the other two phospholes. These reactions show that simple phospholes in general, in contrast to heavily substituted phospholes, are quite good nucleophiles in organic reactions and the results of this study are consistent with a relatively easily perturbed aromatic structure for these phospholes.
Recherches sur le benzofuranne. LXII. Orientation de la nitration de benzofurannes substitués en 2 par un groupement électro‐attracteur
Authors: Lamotte Geneviève , Demerseman Pierre , Royer René 
Published: April 2009

AbstractLa nitration par l'acide nitrique dans l'anhydride acétique des acétyl‐2, carbéthoxy‐2 et cyano‐2 benzofurannes s'effectue principalement en 5 et en 6, accessoirement en 4 et éventuellement en 7. Dans les deux premiers cas, il y a en outre remplacement du substituant en 2 par le groupement nitro.
Benzo[b]thiophene derivatives. XXIII. Derivatives of 5,6‐dihydroxy‐3‐benzo[b] thienylacetic acid
Authors: Campaigne E. , Homfeld E. , Mais Dale E. 
Published: April 2009

AbstractA series of 5,6‐disubstituted benzo[b]thiophenes have been synthesized for biological evaluation. These include analogs of tryptamine, melatonin and harmaline types, having hydroxy, methoxy, methoxymethyloxy, or isopropylidenedioxy groups at both the 5‐ and 6‐ positions. In order to synthesize these, the appropriate mercaptoguaiacols were prepared, and condensed with chloroacetoacetic esters to the 4‐arylthioacetoacetic esters. Cyclization of these ketones was best accomplished when the free phenolic groups were masked by methoxymethyl groups. The benzo[b] thienylacetic esters were then converted to corresponding amides, reduced to tryptamine analogs, acetylated to melatonin analogs, and cyclized to harmaline analogs. N‐Acetyltryptamine and 1‐methylmelatonin were also synthesized for comparison. Preliminary bioassay results on the melatonin analogs, which showed activity, are reported.
Meso‐heterocyclic analogues of 9,10‐dihydroanthracene. XIV. Some indoles and carbazoles derived from phenoxathiin
Authors: Coïc J‐P. , Saint‐Ruf G. 
Published: April 2009

Abstract2‐Aminophenoxathiin undergoes easy condensation with different ω‐bromoketones to give 2‐aroylmethylaminophenoxathiins. These compounds give pyrrolo[2,3‐b]phenoxathiins by the Möhlau‐Bischler cyclisation. Some carbazolo[2,1‐b]phenoxathiins were also synthesised from 7‐oxo‐7,8,9,10‐tetrahydrobenzo[b] phenoxathiin.
The reactivity of the A‐CH=N‐NR‐CX‐B system. 1,3,4‐Oxadiazoles and 2,3,4,5‐tetrahydro‐1,2,4‐triazin‐3‐ones through the 1–5 and 1–6 cyclization reactions of α‐thienylglyoxal monosemicarbazones
Authors: Werber Giuseppe , Buccheri Francesco , Vivona Nicolò , Gentile Manlio 
Published: April 2009

AbstractThe factors influencing the reactivity of α‐thienylglyoxal monosemicarbazones when treated with cyclizing reagents (bromine/sodium acetate and hydrobromic acid in acetic acid) were investigated. Depending on the experimental conditions, on the position of the substituent on the semicarbazide residue, and on the cyclizing agent, the substrates 1a‐e give the semicarbazone bromides 2a‐b, 5, the 1,3,4‐oxadiazoles 3a‐c, the 1,2,4‐triazine 11 and the 2,3,4,5‐tetrahydro‐1,2,4‐triazine‐3‐ones 6, 8 and 9. Compound 6 by thermolysis undergoes ring contraction in the Δ2‐1,3,4‐oxadiazoline 12, while treatment with base involves the conversion of 6 into 1,2,4‐triazol‐5‐one 13. Ir, nmr and mass spectra support the reported structures.
Condensed benzopyrans III. 3H,4H[1] benzopyrano [3,4‐b] pyrrol‐4‐ones
Authors: Khan Misbahul Ain , De Brito Morley Maria Lucia 
Published: April 2009

AbstractThe diazotization of 3‐aminocoumarin followed by its reduction gave the cournarin‐3‐yl‐hydrazine which, without isolation, reacted with various carbonyl compounds in a Fisher's indohzation reaction to give derivatives (Ib‐Ih) of the yet unreported system 3H,4H[1]benzopyrano[3,4‐b]pyrrol‐4‐one.
The synthesis and characterization of some cyclic N‐cyanoguanidines
Authors: Bristol James A. 
Published: April 2009

AbstractThe sodium hydroxide catalyzed synthesis of several cyclic N‐cyanoguanidines (8,10) from dimethyl cyanoimidodithioearbonate (2) and the appropriate aniline derivative (4,5) is described. Base‐induced di‐N‐alkylation to afford 9 and 11 occurs readily.
The reaction of 3‐hydroxypyridine N‐oxide with active hydrogen compounds and the synthesis of 3‐substituted 2‐aminofuro[3,2‐b] pyridines
Authors: Stein M. Luisa , Manna Fedele , Lombardi Carmine C. 
Published: April 2009

Abstract3‐Hydroxypyridine N‐oxide reacts readily in acetic anhydride with ethyl cyanoacetate, cyanoacetone and malononitrile. The three reaction products (2‐substituted‐3‐acetoxypyridines) show different equilibria between tautomeric structures; in strong acids they undergo cyclization to 3‐substituted 2‐aminofuro[3,2‐b]pyridines.
Réactivité de spirochromènes et de mérocyanines azahétérocycliques vis‐à‐vis de quelques agents nucléophiles
Authors: Maguet Michel , Guglielmetti Robert 
Published: April 2009

AbstractLes spirochromènes azahétérocycliques saturés réagissent avec les agents nucléophiles comme l'eau, l'hydrogène sulfuré et le borohydrure de sodium. Ils subissent alors une ouverture soit de leur partie hétérocyclique azotée, soit de leur partie chroménique, soit des deux simultanément. Quant aux mérocyanines, elles peuvent ětre soit partiellement réduites, soit décomposées par le borohydrure de sodium.
Fluoroazoles. III. Synthesis and 1H and 1–9F nmr spectra of 3‐, 4‐, and 5‐fluoro‐1‐methylpyrazole
Authors: Fabra Francesc , Vilarrasa Jaume , Coll Josep 
Published: April 2009

AbstractThe three monofluoro derivatives of N‐methylpyrazole have been synthesized. 3‐Fluoro‐1‐methylpyrazole and 4‐fIuoro‐1‐methylpyrazole were prepared from the appropriate amines by diazotization and photochemical irradiation of the diazonium salts in tetrafluoroboric acid. 5‐Fluoro‐1‐methylpyrazole was obtained from 1‐acetyl‐3‐fluoropyrazole and methyl fluorosulfonate, and also by direct methylation of 3(5) fluoropyrazole with dimethyl sulfate. The 1–9F chemical shifts of these N‐methylated fluoroazoles cover a great range (ca. 50 ppm) and show a good correlation with the chemical shifts of H3, H4, and H5 protons of 1‐methylpyrazole. An unexpected long‐range coupling 5J (F‐CH3) is observed in 3‐fluoro‐1‐methylpyrazole.
Selenium heterocycles XXVII . Synthesis of Thieno[2,3‐d] thiazole and Selenolo[3,4‐d]thiazole. Two novel heterocycles
Authors: Shafiee A. , Mazloumi A. 
Published: April 2009

AbstractStarting from the readily available aryl 2‐substituted‐4‐methyl‐5‐thiazolyl ketones, a series of 2,6‐disubstituted‐thieno[3,4‐d]thiazoles and 2,6‐disubstituted‐selenolo[3,4‐d]thiazoles were prepared. The structures of these compounds were confirmed by analytical, spectroscopic methods and through the reaction with dimethyl acetylenedicarboxylate.
Chemistry of benzo[b] furan IV.. Chemical behaviour of furo[3,4‐b] ‐benzofuran and synthesis of 4‐Arylbenzofuro[2,3‐d] pyridazines
Authors: Shafiee A. , Behnam E. 
Published: April 2009

AbstractFuro[3,2‐b]benzofuran was demonstrated to be an intermediate for the synthesis of dibenzofuran and 1,4‐epoxy‐1,4‐dihydrodibenzofuran ring systems. Starting from the readily available aryl 3‐bromomethyl‐2‐benzo[b]furyl ketones, a method was developed for the synthesis of 4‐arylbenzofuro[2,3‐d]pyridazines.
Addition reactions of heterocycles. VII. Pyrrole and C‐Acetyl‐N‐phenylnitrilimine
Authors: Ruccia Michele , Vivona Nicolò , Cusmano G. , Macaluso Gabriella 
Published: April 2009

AbstractThe addition reaction of C‐acetyl‐N‐phenylnitrilimine to pyrrole has been investigated. The products obtained show that the reaction proceeds via two distinct pathways. The 1,3‐addition reaction leads to the non‐cyclic‐adduct III, whereas the 1,3‐cycloaddition reaction gives a mixture of regioisomeric Δ2‐pyrroline IV and V, and Δ1 ‐pyrroline VI and VII mono‐cycloadducts. These latter compounds cannot be isolated because they undergo a further 1,3‐cycloaddition reaction leading to the N‐substituted bis‐adducts X and XI, and to the bis‐adduets XII and XIII. The stereochemical assignment for X, XI, XII and XIII is provided by nmr data which suggest also that in X and XI the rotation around the exocyclic N‐C bond is relatively slow on the instrument time scale.
The synthesis of some pyrido[1,4] benzoxazepines and a dipyrido[1,4] oxazepine
Authors: Brewster Keith , Harrison John M. , Inch Thomas D. 
Published: April 2009

AbstractSynthetic routes to pyrido[2,3‐b]‐, pyrido[4,3‐b]‐, pyrido[3,2‐f] [1,4]benzoxazepines and dipyrido[2,3‐b:2,3‐f] [1,4]oxazepine are described. The applicability of one of the methods to dibenz[b,f] [1,4]oxazepine synthesis is discussed.
The reductive ring opening of some derivatives of isatin
Authors: Ashby John , Ramage E. M. 
Published: April 2009

AbstractTreatment of two isatin‐3‐imines, 3‐isopropyIamino‐1‐methylindoline‐2‐one and 3‐cyclohexylamino‐1‐methylindolin‐2‐one with sodium borohydride produced the fully‐reduced anilines 2‐isopropylamino‐2‐(2‐methylaminophenyl) ethanol and 2‐cyclohexylamino‐2‐(2‐methylaminophenyl) ethanol, respectively. Reductive ring‐opening of derivatives of isatin is not observed in related examples when either catalytic or lithium aluminum hydride reduction are employed and it is concluded that the present effect is dependant upon the softness of sodium borohydride as a reducing agent.
Tetracyclic phenothiazines V. Construction of the azepino[3,2,1‐kl] ‐phenothiazine ring system by regioselective ring expansion
Authors: Kim Sun H. , Martin Arnold R. 
Published: April 2009

AbstractSolvolysis of 1,2‐dihydro‐3‐hydroxy‐3‐(p‐toluenesolfonyloxymethyl) 3H‐pyrido[3,2,1‐kl]‐phenothiazine gave 1,2,3,4‐tetrahydroazepino[3,2,1‐kl]phenothiazin‐3‐one.
Synthesis of 1‐amino‐4‐chloroisoquinoline. A new approach to 1‐aminoisoquinoline
Authors: Nuvole Antonio , Pinna Gérard Aimé 
Published: April 2009

AbstractThe as yet unknown 1‐amino‐4‐chloroisoquinoline was synthesised from 1,4‐dichloroisoquinoline through the 1‐phenoxy‐4‐chloro derivative. This procedure was also suitable for obtaining 1‐aminoisoquinoline from 1‐chloroisoquinoline in good yields.
Synthesis and reduction of some 1H‐2,1,3‐benzothiadiazin‐4(3H) one 2,2‐dioxides
Authors: Bancroft Keith C. C. , Guindi Laila H. Morcos , Temple Arthur F. 
Published: April 2009

AbstractSeveral 2,1,3‐benzothiadiazin‐4(3H) one 2,2‐dioxides were synthesized as possible sweetening agents by reacting sulfamoyl chloride with various anthranilic acid derivatives. The isolation of 1‐methyl‐4‐methoxy‐2,1,3‐benzothiadiazine 2,2‐dioxide and preparation of 3,4‐dihydro‐2,1,3‐benzothiadiazine 2,2‐dioxide is also reported.
An efficient synthesis of 3‐aminoisothiazolo[5,4‐b] ‐quinoline from quinoline
Authors: Iijima Ikuo , Rice Kenner C. 
Published: April 2009

AbstractTreatment of readily available 3‐formylquinoline‐2‐thiol (1) with ammoniacal sodium hypochlorite directly afforded isothiazolo[5,4‐b]quinoline (3) in high yield, probably via 3‐formylquinoline‐2‐sulfenamide (2). Facile conversion of 3 to the corresponding 3‐amino derivative (7) was accomplished by the following sequence: base induced opening of the isothiazole ring to 3‐cyanoquinoline‐2‐thiol (5), oxidation of 5 to the corresponding stable sulfenamide (6) and sodium ethoxide catalysed reclosure of the isothiazole ring which provided 3‐aminoisothiazolo[5,4‐b]quinoline (7).
Preparation of ethyl 1‐hydroxy‐2‐naphthoates from 1H‐2‐benzopyran‐1‐ones: A new method
Authors: Hauser Frank M. , Pogany Stefano A. 
Published: April 2009

AbstractLithio ethyl acetate is a superior reagent for the transformation of 1H‐2‐benzopyran‐1‐ones to naphthoates.
Chemistry of the phenoxathiins VI. An examination of the 1–3C‐1H coupling constants of 1‐azaphenoxathiin by selective excitation fourier transform 1–3C‐NMR
Authors: Martin Gary E. 
Published: April 2009

AbstractThe complete examination of coupled 1–3C‐nmr spectra of complex heterocyclic systems is seldom attempted because of the inherrent complexity of these spectra, arising through extensive spin‐multiplet overlapping. The utilization of the selective excitation technique, in combination with gated decoupling for the specific re‐examination of the primary coupling constants of resonances at the 4‐ and 6‐positions of the 1‐azaphenoxathiin ring system is described.
Kinetic evidence for the unusual path in the hydrolysis of amides. pH‐rate profile for N‐trifluoroacetylindole
Authors: Cipiciani Antonio , Linda Paolo , Savelli Gianfranco 
Published: April 2009

AbstractThe first complete pH‐rate profile (HO‐4 ÷ pH 12) for an amide is reported. Hydration of carbonyl moiety is suggested to be the first step of the reaction between HO‐4 ÷ pH 6.
Synthesis and spectroscopic studies of some heterocyclic compounds. Reaction of 3‐aryl‐1‐phenyl‐2‐propen‐1‐ones with ethyl phenylacetate
Authors: Al‐Farkh Yousuf A. , Al‐Hajjar Farouk H. , Hamoud Hayat S. 
Published: April 2009

Abstract3‐Aryl‐1‐phenyl‐2‐propen‐1‐one I reacted with ethyl phenylacetate (II) in the presence sodium ethoxide at room temperature to give the corresponding ethyl β‐aryl‐γ‐benzoyl‐α‐phenyl‐butyrate III. However,' when the same ketones were refluxed with ethyl phenylacetate, they gave the corresponding 4‐aryI‐3,6‐diphenyl‐3,4‐dihydro‐2H‐pyran‐2‐ones IV. The reactions of III and IV with hydrazine hydrate afforded the corresponding hydrazones VI and 2‐pyridones VIII, respectively. The structure and configuration of the products are based on chemical and spectroscopic evidence.
Nouvelle voie de synthèse des dérivés de l'ellipticine et analogues alcaloïdes à activité antitumorale
Authors: Gilbert Jacques , Rousselle Dominique , Gansser Charles , Viel Claude 
Published: April 2009

AbstractLes auteurs rapportent une voie originate d'accès aux 6H‐pyrido[4,3‐b]carbazoles, qui est aisément mise en oeuvre à partir de cyclohexanones convenablement substituées. Elle réalise la fusion des synthèses de Borsche d'obtention des carbazoles et de Cranwell et Saxton de preparation de l'ellipticine, et présente le double avantage de la commodité d'accès des matières premières et d'une aromatisation effectuée dès la seconde étape. Les 7H‐pyrido[3,4‐c]‐carbazoles ne sont obtenus que lore de la preparation des desméthyl‐11 ellipticines.
New heterocyclic ring systems. IX. Polyazadithiasteroid analogues
Authors: Fravolini A. , Schiaffella F. , Strappaghetti G. 
Published: April 2009

AbstractThe synthesis of the novel tricyclic ring 5‐rnethyl‐4‐oxo‐2,3,4,5‐tetrahydrothiopyrano[3,2‐c]‐[1,2]benzothiazine 6,6‐dioxide (III) is described.By the reaction of hydrazine and hydroxylamine with the glyoxylate (IV) and ester (V) obtained from III, several polyazadithiasteriod analogues have been synthesized.
Réactions induites par ies halogénures de pyridinium. XXVII. Sur la formation d'ethers cycliques par action du chlorure ou du bromure de pyridinium sur l'hexanediol‐2,5
Authors: Dauzonne Daniel , Demerseman Pierre , Royer René , Lang Catherine , Ratzer Nicole 
Published: April 2009

AbstractIl est montré que la cyclodéshydratation des hexanediols‐2,5 en diméthyl‐2,5 tétrahydrofurannes peut ětre effectuée au moyen du chlorure ou du bromure de pyridinium, aussi bien qu'avec n'importe quel autre réactif précédemment utilise' pour cela. On détermine les diverses réactions secondares qui accompagnent alors cette cyclodéshydratation et on précise par quels mécanismes elle s'effectue.
Organische photochemie XXI. 9H‐cyclopenta[b] [1]benzoselenin ‐ein neues heterocydisches ringsystem
Authors: Praefcke Klaus , Schmidt Dietmar 
Published: April 2009

AbstractBy way of a photo‐induced selenolester‐seleninone rearrangement, the derivative 5 of a new heterocyclic ring system, 9H‐cyclopenta[b][1]benzoselenin, has been formed. This rearrangement occurs via a new photosubstitution reaction of S‐aryl‐ in competition with Se‐aryl‐groups, followed by photocyclization using 2‐p ‐tolythiocyclopentene ‐1 ‐ selenocarbonic acid Se‐p‐tolylester (1a) as starting materials. As a competing product in this photo‐rearrangement, a second heterocycle, 7‐methylcyclopenta[b] [1]benzothiopyrone (4) (9) has been formed via an intramolecular photochemical Friedel Crafts reaction.
13C Nmr study of 1,2,4‐triazino[4,5‐b]indazole derivatives
Authors: Rabaron Alain , Lancelot Jean‐Charles , Maurne Daniel , Robba Max 
Published: April 2009

AbstractThe main nmr parameters of 1,2,4‐triazino[4,5‐b]indazole derivatives were measured on the basis of their 13C nmr spectral analysis compared to indazole models. 1J C‐H coupling constants were studied and the correct structure of 1,2,4‐triazino[4,5‐b]indazoles was elucidated.