bluuebunny/crossref_metadata_2025 huggingface dataset:
Isothiazoles IX. Halogenation of 2‐substituted‐4‐isothiazolin‐3‐ones
Authors: Weiler Ernest D. , Petigara Ramesh B. , Wolfersberger Martha H. , Miller George A.
Published: April 2009

Bromination of 4‐isothiazolin‐3‐ones, I, gave the 4‐bromo derivatives, III, in good yields, while formation of 4,5‐dibromo derivatives, IV, was much more difficult. In contrast, chlorination of I, even under mild conditions, gave primarily 4,5‐dichloro derivatives, VI, and lesser amounts of the 4‐chloro derivatives, V. Vigorous bromination of the 4‐methyl analog of I gave the 5‐bromo derivatives, VIII, whereas mild chlorination gave predominantly the 4,5,5‐trichloro derivatives, X.
Substituted pyrimidines. II. 1,3‐Dimethylisocytosine and related compounds
Authors: Maehr Hubert , Smallheer Joanne , Toome Voldemar
Published: April 2009

1,3‐Dimethyl‐1,2‐dihydro‐2‐imino‐4(3H)pyrimidinone (1,3‐dimethylisocytosine) was prepared by methylation of 2‐amino‐3‐methyl‐4(3H)pyrimidinone and was degraded in alkaline solution to a mixture of 3‐methyl‐2‐methylamino‐4(3H)pyrimidinone, 1,3‐dimethyl‐2,4‐(1H,3H)pyrimid‐indione, 2‐methylamino‐l‐methyl‐4(1H)pyrimidinone, 1‐methyl‐2,4‐(1H,3H)pyrimidindione and 3‐methyl‐2,4‐(1H,3H)pyrimidindione. Thiation of the title compound gave both 1,2‐dihydro‐1,3‐dimethyl‐2‐thio‐4(3H)pyrimidinone and 1,3‐dimethyl‐2,4‐(1H,3H)pyrimidinedithione. The title compound is a tautomerically fixed pyrimidine and its uv spectra were compared with related compounds, notably 3‐methyl‐2‐dimethylarnino‐4(3H)pyrimidinone which is also tautomerically fixed.
Heterocycles from ketenimines XI. Oxindoles
Authors: Barker Marvin W. , Sung Hsiu‐Sun
Published: April 2009

The reaction of ketenimines with heterocyclic N‐oxides yields N‐substituted oxindoles. Hydrolysis of these adducts or acid work‐up of the original reaction mixtures leads directly to oxindoles in which the nitrogen atom is unsubstituted.
1,2,4‐Triazoles from formic acid‐Induced rearrangement of 6‐(Phenylhydrazino)uracils
Authors: Wright G. E.
Published: April 2009

The structure of a rearrangement product of 6‐(phenylhydrazino)uracil + formic acid has been proved to be 1‐phenyl‐3‐carboxamidomethyl‐1,2,4‐triazole: hydrolysis of this compound and thermal decarboxylation of the intermediate acid gave the known 1‐phenyl‐3‐methyl‐1,2,4‐triazole. Yields of triazoles from substituted 6‐(phenylhydrazino)uracils follow inversely yields of pyrimidoindoles derived from Fischer‐type cyclization [J. Heterocyclic Chem., 13, 539 (1976)]. The lack of formation of a triazole from 3‐methyl‐6‐(phenylhydrazino)uracil suggests that an intermediate in this rearrangement, ie., that resulting from formylation of the anilino nitrogen atom followed by intramolecular cyclization involving the uracil 1‐nitrogen atom, must undergo conjugate elimination of water to generate the triazole ring.
A new route to the phosphindole system
Authors: Holah David G. , Hughes Alan N. , Kleemola Daniel
Published: April 2009

A new and possibly general route to the hitherto relatively inaccessible simple substituted phosphindoles, utilizing the extreme readiness of simple phosphole sulfides to undergo Diels‐Alder dimerization, is described. The synthesis reported here is that of 3,6‐dimethyl‐l‐phenylphosphin‐dole sulfide which is prepared in good yield in two simple steps from the readily available 3‐methyl‐l‐phenylphosphole.
Oxidative reactions of polyarylpyrroles. II. Oxidative dimerization with dichromate
Authors: Sprio Vincenzo , Petruso Salvatore , Ceraulo Leopoldo , Lamartina Liliana
Published: April 2009

The behaviour of 2,4,5‐triphenylpyrrole and 2‐(p‐tolyl)‐4,5‐diphenylpyrrole under oxidation conditions with dichromate has been investigated. The several reaction products obtained were separated by column cliromatography. In addition to products previously obtained using other oxidizing agents (2), additional products were isolated, namely, the 2,3′‐dimers IIIa.b and related oxygenated products Va,b and VIa,b. Their structures were assigned by means of elemental analyses, chemical behaviour and spectroscopic data (ir, uv, nmr andms).
Chlorosulfonation of 2‐arylimidazoles
Authors: Baldwin J. J. , Lumma P. K. , Ponticello G. S. , Novello F. C. , Sprague J. M.
Published: April 2009

The chlorosulfonation of 2‐arylimidazoles was investigated; the resulting sulfonyl chloride derivatives were isolated and characterized as the corresponding sulfonamides. When the 2‐aryl substituent was 3,4‐dichlorophenyl or 3‐pyridyl, chlorosulfonation occurred only on the imidazole ring. The chlorosulfonation of 2‐(4‐chlorophenyl)imidazole was temperature dependent, yielding either a mono or disulfonamide after treatment with ammonia. The structure of this disulfon‐amide was determined from pmr spectra to be 2‐(4‐chloro‐3‐sulfamoyl)‐4(5)sulfamoylimidazole.
Photosensitized cyclodimerizations of 4‐vinylpyridine, 2‐vinylpyridine, and 2‐vinylquinoline
Authors: Nakano Tatsuhiko , Martín A. , Rivas C. , Pérez C.
Published: April 2009

Irradiations of 4‐vinylpyridine and of 2‐vinylpyridine in either f‐butyl alcohol or benzene, with benzophenone, yielded a single photodimer, which, on the basis of the nmr and mass spectral data, was assigned the trans‐head‐to‐head structure (I). Upon irradiation in either t‐butyl alcohol or benzene, in the presence of benzophenone, 2‐vinylquinoline gave a single photodimer whose structure and stereochemistry were also determined from the nmr and mass spectral evidence as (V). Irradiation of 2‐vinylquinoline in benzene, in the absence of benzophenone, also gave rise to the same photodimer, but, when t‐butyl alcohol or methanol was used as a solvent, no dimer formation was observed.
Intramolecular 1,3‐cycloadditions of nitrile ylides bearing an acetylenic function
Authors: Garanti Luisa , Padova Giovanna , Zecchi Gaetano
Published: April 2009

Treatment of amides 1a,b with thionyl chloride followed by reaction with triethylamine gave 1,4‐dihydro[1]benzopyrano[4,3‐b]pyrrole derivatives (4a,b) arising from intramolecular 1,3‐cycloaddition of intermediate nitrile ylides (3a,b).
The novel one step syntheses of benzobis‐ and benzotris[1,2,5]thiadiazole
Authors: Mataka Shuntaro , Takahashi Kazufumi , Tashiro Masashi
Published: April 2009

The reaction of tetrasulfur tetranitride with alkoxybenzenes such as anisole (1a), o‐ (1b), m‐(1c), p‐dimethoxybenzenes (1d), and benzyl ether (1e) was investigated. Benzo[1,2‐c:3,4‐c′ :5,6‐c ]‐tris[1,2,5]thiadiazole (2) and benzo[1,2, c:3,4‐c′ ]bis[1,2,5]thiadiazoles (3a and 3b) were isolated. J. Chem. Soc., 14, 963 (1977)
Synthesis of 4H‐furo[3,2‐b]indole derivatives A new heterocyclic ring system
Authors: Tanaka Akira , Yakushijin Kenichi , Yoshina Shigetaka
Published: April 2009

4H‐Furo[3,2‐b]indole (III) was prepared from deoxygenation of 2‐(2‐nitrophenyl)furan (II) with triethyl phosphite and thermolysis of 2‐(2‐azidophenyl)furan (VI). 4H‐ or 4‐alkylfuro [3,2‐b]indole‐2‐carboxaldehydes (VIII, IXa‐c) were obtained by Vilsmeier formylation of the corresponding furo[3,2‐b]indoles (III, VIIa‐c). 4H‐Furo[3,2‐b]indole‐2‐carboxaldehyde (VIII) was submitted to the Cannizzaro, Wittig and reduction reactions. The Shiff's bases were obtained by the reaction of 4‐ethylfuro[3,2‐b]indole‐2‐carboxaldehyde (IXb) with amines. J. Heterocyclic Chem., 14, 975 (1977)
Synthesis of 5‐amino‐2,3‐dihydro‐1H‐1,4‐benzodiazepines
Authors: Corral Carlos , Madroñero Ramón , Vega Salvador
Published: April 2009

A number of 5‐amino‐2,3‐dihydro‐lH‐1,4‐benzodiazepines (II) have been prepared from the reaction of 5‐methylmercapto‐2,3‐dihydro‐1H‐1,4‐benzodiazepine (I) with amines. Another alternate approach based on the cyclodehydration of the ureic compounds (IV) was unsuccessful. The synthesis of I was accomplished by methylation of the 1,2,3,4‐tetrahydro‐5H‐5‐thioxo‐1,4‐benzodiazepine (VI) with dimethyl sulfate in methanol‐dioxane. Another attempted method for the synthesis of I is also presented. J. Heterocyclic Chem., 14, 985 (1977)
1,3‐Oxazolidin‐4‐ones. Synthesis and configuration of cis and trans isomers
Authors: Pilgram Kurt , Pollard Glenn E.
Published: April 2009

Mixtures of cis and trans 1,3‐oxazolidin‐4‐ones were obtained by cyclodehydration, in the presence of p‐toluenesulfonic acid or boron trifluoride etherate, of lactamide and N‐methyl‐lactamide with aromatic and aliphatic aldehydes. The products were separated by column (silica) chromatography and their configurations were determined.
4(And 5)‐cyclopropylamino‐5(and 4)halo‐3(2H)pyridazinones. Formation and characterization of isomers
Authors: Pilgram Kurt H. , Pollard Glenn E.
Published: April 2009

The reactions of 4,5‐dihalo‐3(2H)pyridazinones with ammonia and amines gave mixtures of 5‐amino‐4‐halo‐ and 4‐amino‐5‐halo‐3(2H)pyridazinones separated by chromatography. Structures were elucidated by means of retention values (Rf) and confirmed by independent synthesis.
Aqueous synthesis of a new 1,3,2‐diazaphospholidine
Authors: Schenkenberg Philip R. , Williams Charles R.
Published: April 2009

N,N,N'‐Trimethylphosphoric triamide reacts with aqueous glyoxal to produce a 1,3,2‐diaza‐phospholidine 5‐membered ring system (III) in good yield. The ease of this synthesis belies the results with other phosphoramides where no cyclic species could be isolated.
Intramolecular substitution of unactivated aryl groups by thioamide anion
Authors: Spitulnik M. J.
Published: April 2009

The general reaction of intramolecular nucleophilic substitution of unactivated aryl groups by thioamide anion in dipolar aprotic amide solvent is extended by the syntheses of 6‐chloro‐5‐methoxy‐2‐methylbenzothiazole from 2′,4′‐dichloro‐5′‐methoxythioacetanilide and 6‐methoxy‐2‐methylbenzothiazole from 4′‐methoxy‐2′‐nitrothioacetanilide. The six‐membered fused ring heterocycles, 2‐methyl‐4H,3‐benzothiazine and 6,8‐dichloro‐3‐rnethyl‐1H‐4,1,2‐benzothiadi‐azine are also prepared.
Formation of a pyrazopyrazolone by the pyrolysis of antipyrine diazonium fluoroborate
Authors: Robbins Philip J.
Published: April 2009

The pyrolysis of antipyrine 4‐dizaonium fluoroborate gave an antipyrylazopyrazopyrazolone instead of the desired 4‐fluoroantipyrine. This compound was formed by intermolecular and intramolecular coupling of the diazo compound at elevated temperatures. J. Heterocyclic Chem., 14, 1107 (1977)
Some derivatives of 1,8‐naphthyridine, 1,2‐dihydropyrindo[2,3‐B][1,8]‐naphtyridine and 2H‐pyrano[2,3‐b][1,8]naphtyridine
Authors: Henery Ronald A. , Hammond Peter R.
Published: April 2009

The pyrolysis of antipyrine 4dizaonium flouroborate gave an antipyrylazopyrazopyrazolone instead of the desired 4‐fluoroantipyrine. This compound was formed by intermolecular and intramolecular coupling of the diazo compound at elevated temperatures.
Nucleosides. CIX. 2′‐Deoxy‐ψ‐isocytidine, 2 ‐deoxy‐ψ‐uridine, and 2′‐deoxy‐l‐methyl‐ψ‐uridine. Isosteres of deoxycytidine, deoxyuridine and thymidine
Authors: Chu C. K. , Reichman U. , Watanabe K. A. , Fox J. J.
Published: April 2009

2′‐Deoxy‐ψ‐isocytidine (VIIβ), a 2′‐deoxy analog of antileukemic ψ‐isocytidine and also a C‐nucleoside analog of deoxycytidine, was synthesized from ψ‐uridine by making use of the newly discovered pyrimidine to pyrimidine transformation reaction [J. Chem. Soc., 14, 537 (1977)]. 2′‐Deoxy‐ψ‐uridine (IIβ) and 2′‐deoxy‐l‐methyl‐ψ‐uridine (V), both C‐nucleoside analogs of deoxyuridine and thymidine, were also synthesized.

ψ‐Uridine was converted into the 2′‐chloro analogs (I) which was reduced with tributyltin hydride to give an α,β‐mixture of 2′‐deoxy‐ψ‐uridines. The β‐isomer (11β was trimethylsilylated and the product (III) treated with methyl iodide to afford the 1‐methyl derivative (IV). After hydrolytic removal of the trimethylsilyl groups from IV, the thymidine analog (V) was obtained in good yield.

A crude mixture of II was converted in good yield into an α,β‐mixture of 1,3‐dimethyl‐2 ‐deoxy‐ψ‐uridines (VI) by treatment with DMF dimethyl acetal in DMF. Treatment of the β‐isomer (VIβ) with guanidine, however, gave the α,β‐mixture of 2 ‐deoxy‐ψ‐isocytidines (VII). The pure β‐isomer (VIIβ) was obtained by thick layer chromatography. The pure α‐isomer (VIIα) was obtained when VIα was treated with guanidine.

2 ‐Deoxy‐ψ‐isocytidine (VIIβ) and 2 ‐deoxy‐l‐methyl‐ψ‐uridine (V) exhibited inhibitory activity against P815 cells (ID5 0 1.2 μg./ml. and 4.9 μg./ml., respectively) and the thymidine analog V was found to be active against Streptococcus faecium var. duran. J. Heterocyclic Chem., 14, 1119 (1977)
Nucleophilic displacement of aromatic fluorine. Part V. Use of nitrogen heterocycles as nucleophiles
Authors: Gilman Norman W. , Holland Betty C. , Walsh Gregory R. , Fryer R. Ian
Published: April 2009

The scope of the nucleophilic displacement of aromatic halogens on 1,4‐benzodiazepine precursors by the anions of pyrroles, pyrazoles and imidazoles was studied both with and without electron‐withdrawing substitutents on the heterocyclic nucleophiles. Some of the products proved to be useful intermediates for the synthesis of novel fused 1,4‐benzodiazepines.
Cycloadditions dipolaires‐1,3 II. Addition des diarylnitrilimines au N‐methyl‐indole. Etude expérimentale et essai d'interprétation
Authors: Laude Bernard , Soufiaoui Mohamed , Arriau Et Jean
Published: April 2009

On étudie la réactivite du N‐méthylindole vis‐à‐vis de plusieurs diarylnitrilimines. Les cycloadduits obtenus sont des dérivés du méthyl‐8 dihydro‐3a,8a pyrazolo [3,4‐b] indole. La structure proposée est en accord avec les données analytiques et spectrales. Elle est confirmée par voie chimique. Une interprétation fondee sur la méthode de perturbation au second ordre des propriétés des orbitales frontières rend compte de la régiospécificité observée.
Synthesis and antimalarial effects of [1]benzothieno[3,2‐f]quinazoline‐1,3‐diamine
Authors: Johnson Judith , Elslager Edward F. , Werbel Leslie M.
Published: April 2009

Bromination of 2‐dibenzothiophenamine has been shown to afford 1‐bromo‐2‐dibenzothio‐phenamine rather than the previously reported 3‐isomer. This material was converted to the 1‐cyano derivative and cyclized with chloroformamidine hydrochloride to [l]benzothieno‐[3,2‐f]quinazoline‐1,3‐diamine. Both this and the corresponding 7,7‐dioxide were devoid of antimalarial activity.
Reactivity of 2‐amino‐1,3,4‐thiadiazoles. Nucleophilic behaviour of some 2‐amino‐1,3,4‐thiadiazoles: Model compounds
Authors: Werber Giuseppe , Buccheri Francesco , Gentile Manlio
Published: April 2009

The ambident nucleophilic behaviour of some 2‐amino‐5‐H‐1,3,4‐thiadiazoles in alkylation, acylation and nitrosation reaction has been verified. The structures assigned to the 2‐amino‐1,3,4‐thiadiazoles (1a‐i) and to the Δ2‐1,3,4‐thiadiazolines (2a‐e) agree with the spectral data.
Synthesis of imidazo[4,5‐d]pyridazine nucleosides related to inosine
Authors: Dan Cook P. , Dea Phoebe , Robins Roland K.
Published: April 2009

Several imidazo[4,5‐d]pyridazine nucleosides which are structurally similar to inosine were synthesized. Anhydrous stannic chloride‐catalyzed condensation of persilylated imidazo[4,5‐d]‐pyridazin‐4(5H)one (1) and imidazo[4,5‐d]pyridazine‐4,7(5H,6H)dione (16) with 1‐O‐acetyl‐2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranose (3) provided (after sodium methoxide deblocking) 6‐β‐D‐ribo furanosylimidazo[4,5‐d]pyridazin‐4(5H)one (5) and 3,6‐di‐(β‐D‐ribofuranosyI)imidazo[4,5‐d]pyridazin‐4‐one (7); and 1‐(β‐D‐ribofuranosyl)imidazo[4,5‐d]pyridazine‐4,7(5H,6H)dione (19) and 1,5 or 6‐di‐(β‐D‐ribofuranosyl)imidazo[4,5‐d ]pyridazine‐4,7(5H or 6H)dione (21), respeeitvely. 4,7‐Diehloro‐1‐β‐D‐ribofuranosylimidazo[4,5‐d]pyridazine (12) and dimethyl 1‐β‐D‐ribofuranosylimidazole‐4,5‐dicarboxylate (26), both prepared from stannic chloride‐catalyzed ribosylations of the corresponding heterocycles, were converted in several steps to 3‐β‐D‐ribo‐furanosy limidazo[4,5‐d]pyridazin‐4(5H)one (14) and nucleosidc 19, respectively. Acid‐catalyzed isopropylidenation of mesomeric betaine 7 or nuclcoside 14 provided 3‐(2,3‐isopropylidene‐β‐D‐ribofuranosyl)imidazo[4,5‐d]pyrizin‐4(5H)one (31). 1‐β‐D‐Ribofuranosylimidazo[4,5‐d]‐pyridazine (29) was obtained in several steps from nueleoside 12. The structure of the nucleosides was established by the use of carbon‐13 and proton nmr.
Investigations of substituted benzofuran‐3‐carboxylates, benzo[1,2‐b:4,5‐b']difurans and benzo[1,2‐b:4,3‐b']difurans
Authors: McPherson H. L. , Ponder B. W.
Published: April 2009

The Michael addition of ethyl acetoacetate to benzoquinone, toluquinone, and chlorobenzo‐quinone leads to formation of substituted 5‐hydroxybenzofuran‐3‐earboxylates and linear benzo‐[1,2‐b:4,5‐b']difurans. The previously reported structural proof for the benzodifurans obtained from chlorobenzoquinone and toluquinone, although correct in the conclusion, is shown to be invalid. Proof of the linear benzodifuran structures was obtained by comparison of the uv spectra with authentic angular benzo[1,2‐b:4,3‐b']difurans.
Synthesis of heterocyclic compounds VIII. 4H‐Pyrans from α‐benzoylcinnamonitriles
Authors: Quinteiro M. , Seoane C. , Soto J. L.
Published: April 2009

A new synthesis of substituted 4H‐pyrans is reported. The base catalyzed reaction of substituted α‐benzoy]cinnamonitri]es (I) with malononitrile yields 6‐amino‐2,4‐diaryl‐3,5‐dieyano‐4H‐pyrans (III). Similarly, 6‐amirio‐2,4‐diaryl‐5‐carbethoxy‐3‐cyano‐4H‐pyrans (IV) have been prepared Irom ethyl cyanoacetate.
Carbon‐13 magnetic resonance spectra of cocaine metabolites and derivatives
Authors: Baker John K. , Borne Ronald F.
Published: April 2009

The carbon‐13 nmr spectral assignments oi cocaine, O‐benzoylecgonine, ecgonine, norcocaine, O‐benzylnorecgonine, norecgonine, and N‐allylnorcocaine were made. The assignments were primarily based on the correlation of substituent effects within series and selective proton irradiation studies.
Reaction of ketenes with N,N‐disubstituted α‐aminomethyleneketones VII. Synthesis of 2H,5H‐[1]benzothiopyrano[4,3‐b]pyran and 2H,5H‐thiopyrano[4,3‐b]pyran derivatives
Authors: Mosli Luisa , Menozzi Giulia , Schenone Pietro
Published: April 2009

The dipolar 1,4‐cycloaddition of dichloroketerie to N,N‐disubslituled 3‐aminomethylene‐2,3‐dihydro‐4‐thiochromanones and 3‐aminomethylenetelrahydro‐4‐thiopyranones gave N,N‐disubstituted 4‐amino‐3,3‐diehloro‐3,4‐dihydro‐2H,5H‐[1]benzolhiopyrano[4,3‐b]pyran‐2‐ones and 4‐amino‐3,3‐dichloro‐3,4,7,8‐tetrahydro‐2H,5H‐thiopyrano[4,3‐b]pyran‐2‐ones, respectively, only in the ease of aromatic or strong hindering aliphatic N‐substitution. The adducts gave N,N′‐disubstituted 4‐amino‐3‐chloro‐2H,5H‐[1]benzothiopyrano[4,3‐b]pyran‐2‐ones and 4‐amino‐3‐chloro‐7,8‐dihydro‐2H,5H‐thiopyrano[4,3‐b]pyran‐2‐ones, respectively, by dehydro‐chlorination with DBN. By chromatography on neutral alumina, 3‐(2,2‐dichloroethylidene)‐2,3‐dihydro‐4‐thiochromanone was isolated as an unstable liquid from the reaction between dichloroketerie and 3‐diethylaminornethylene‐2,3‐dihydro‐4‐thiochromanone.
The synthesis of covalently linked tetraarylporphyrin dimers
Authors: Little Robert G.
Published: April 2009

A new and general synthesis of porphyrin dimers is described. The synthesis involves the reaction of dibromoalkanes with phenolic porphyrins, such as 5(4‐hydroxyphenyl)‐10,15,20‐tritolylporphyrin, to form σ‐bromoalkyl porphyrin ethers. The latter compounds are then reacted with a second phenolic porphyrin to give porphyrin dimers. A mixed metalloporphyrin dimer has been prepared which contains both V(IV) and Cu(II). The compounds have been examined spectroscopically. The free‐base porphyrin dimers show a splitting of the intense Soret band. This is interpreted as indicative of weak singlet energy transfer between the covalently linked porphyrins.
Synthesis of s‐triazolocycloalkyl‐, s‐triazolobenzocycloalkyl‐, and s‐triazolocycloalkylhydrothiadiazines
Authors: Albrecht William L. , Jones Winton D. , Sweet F. William
Published: April 2009

The reaction of cyclic‐α‐haloketones with 5‐subslituted‐4‐amino‐4H‐1,2,4‐triazole‐3‐lhiols gave s‐triãzolocycloalkylhydrothiadiazines and s‐triazolobenzocycloalkylthiadiazines. Reduetion of the 5,5a‐imine bond of the s‐triazoloeycloalkylthiadiazines gave s‐triazolocycloalkylhydrothia‐diazines.
Hétérocyclisations intramoléculaires par réaction d'oxymercuration III. Régiosélectivité et stéréosélectivité de l'oxymercuration intramoléculaire de phénols orthoallyliques
Authors: Spéziale V. , Dao H. G. , Lattes A.
Published: April 2009

L'oxymercuration intramoléculaire cyclisante de phénols orthoallyliques diversement sub‐stitués sur la chaǐne allylique a été réalisée. La formation d'hétérocycles α cinq chaǐnons est la seule généralement observée sauf lorsque le carbone terminal est substitué. Dans ce dernier cas, l'influence du solvant et du sel mercurique sur la formation de cycles à cinq et à six chaǐnons a été examinee.
Preparation of some 3‐hydroxy‐ and 3‐mercapto‐1,2,4‐triazoles. Reaction of aliphatic selenone esters with semicarbazide and thiosemicarbazide derivatives
Authors: Cohen Victor Israel
Published: April 2009

The synthesis, mass and nrnr spectra of a number of 3‐hydroxy‐ and 3‐mercapto‐1,2,4‐triazoles has been described.
Synthesis of the alkaloid thalactamine and a new synthesis for the alkaloid N‐methyl‐6,7‐dimethoxy‐1(2H)isoquinolone
Authors: Belgaonkar Vasant H. , Usgaonkar R. N.
Published: April 2009

The alkaloid thalactamine (N‐methyl‐5,6,7‐trimethoxy‐1(2H)isoquinolone) was synthesised in two steps from 4,5,6‐trimethoxyhomophthalic acid (1a). Heating la with DMF/POCI3 at 100° furnished thalactamine‐4‐earhoxylic acid which was easily decarboxylated to give the alkaloid thalactamine. By the same two steps, the alkaloid N‐methyl‐6,7‐dimethoxy‐1(2H)‐isoquinolone is obtained from 4,5‐dimethoxyhomophthalic acid. Synthesis for la from 2‐bromogallic acid trimethyl ether was modified to give excellent yield. 5,6,7‐Trimethoxy and 6,7‐dimethoxyisocoumarin‐4‐carboxylic acid esters were synthesised from the homophthalic acids 1a and b by interacting them with DMF/phosphoryl chloride at 0°, to give corresponding 4‐(N,N‐dimethylaminoformylidene)isochroman‐1,3‐dione derivatives Vla and b and treating their alcoholic solutions with dry hydrogen chloride gas. The isocoumarins were converted into N‐methyl‐1(2H)isoquinolonesby treating them with aqueous methylamine. The isochromandione Vla slowly changed into 3‐chloro‐4‐formyl‐5,6,7‐trimethoxyisocoumarin during the working up of the reaction.
The synthesis of macrocyclic ether‐esters, thioether‐esters, and ether‐thiolesters with the oxalyl moiety
Authors: Fore Paul F. , Bradshaw Jerald S. , Nielsen Steven F.
Published: April 2009

A new series of macrocyclic polyether‐diesler compounds (3‐12) have been prepared by treating various oligoethylene glyeols or mercaplans with oxalyl chloride. The compounds prepared were: 1,4,7,10,13‐pentaoxacyclopentadecane‐2,3‐dione (3), 1,4,7,1 3‐tetraoxa‐10‐thiacyclopenta‐decane‐2,3‐dione (4), 1,4,10‐lrioxa‐7,13‐dithiacyclopenladecane‐2,3‐dione (5), 1,4,7,10,13,16‐hexaoxacyclooctadecane‐2,3‐dione (6), 1,4,7,10,13, 16‐hexaoxacyclooctadecane‐2,3,11,12‐tetra‐one (7), 1,4,10,13‐tetraoxa‐7,16‐dithiacyclooctadecane‐2,3,11,12‐tetraone (8), 7,16‐dioxa‐1,4, 10,13‐letralhiacyclooctadecane‐2,3,11,12‐tctraone (9), 1,4,7,10,13,16‐hexathiacyclooctadecane‐2,3,11,12‐tetraone (10), 1,4,7,10,13,16,19‐heptaoxacyclohencicosane‐2,3‐dione (11), and 1,4,7, 10,13,16,19,22‐octaoxacyclolelracosane‐2,3,14,15‐letraone (12).
Heterocyclic fused tropylium ions VII. On the synthesis of 9H‐dithieno[2,1 ‐b:4,5‐c′]tropylium fluoborate and 4H‐dithieno[1,2‐b:4,5‐c′]tropylium fluoborate
Authors: Yom‐Tov Baruch , Cronowitz Salo
Published: April 2009

9H‐Dithieno[2,1 ‐b:4,5‐c′]tropylium ion (III) and 4ii‐dithieno[1,2‐b:4,5‐c′]tropylium ion (IV) have been synthesized by ring‐closure of 1‐(4‐carboxy‐3‐thienyl)‐2‐(3′‐thienyl)ethane (IX) and 1‐(4‐carboxy‐3‐thienyl)‐2‐(2′‐thienyl)ethane (XVI), respectively, followed by bromination‐debrom‐ination to 9H‐cyclohepta[2,1‐b:4,5‐c′] dithiophen‐9‐one (XI) and 4H‐cyclohepta[1,2‐b:4,5‐c′]‐dithiophen‐4‐one (XVIII), and finally by reduction and hydride transfer. The tropylium ions III and IV were less stable than the [b,b′]‐fused isomers previously studied.
Synthesis of 3‐aryl‐4‐oxothiazolin‐2‐yl(4‐ethoxy‐3‐methoxy)phenyl hydrazones as possible anticonvulsants
Authors: Dimri A. K. , Parmar S. S.
Published: April 2009

Several 3‐aryl‐4‐oxo‐thiazolin‐2‐yl(4‐ethoxy‐3‐methoxy)phenyl hydrazones were synthesized and evaluated for their anticonvulsant activity. Three of these substituted hydrazones provided 80% protection against pentylenetetrazol‐induced convulsions in mice.
Synthèse de flavones et de xanthones dans la série du benzo[4,5]thiophène
Authors: Netchitailo P. , Decroix Bernard , Morel Jean , Pastour Paul
Published: April 2009

Nous décrivons les premières synthèses d'aryl‐2 benzo[4,5]thiéno[2,3‐b]pyrannone‐4 et d'aryl‐2 benzo[4,5]thiéno[3,2‐b] pyrannone‐4 à partir du benzo[4,5]thiophène, et étendons ces cyclisations pour obtenir des hétérologues des xanthones.
5‐Vinylpyrimidines. Synthesis via organopalladium intermediates
Authors: Arai Isamu , Daves G. Doyle
Published: April 2009

Reactions of 1,3‐dimethyl‐5‐iodouracil or 2,4‐dimethoxy‐5‐iodopyrimidine with vinyl acetate in the presence of a catalytic amount of diacetato‐bis (triphenylphosphine) palladium (II) resulted in good yields of the corresponding 5‐vinylpyrimidines. The reactions are viewed as resulting from regioselective addition of an initially formed 5‐pyrimidinyl palladium species to the double bond of vinyl acetate followed by elimination of a palladium acetate with regeneration of the double bond and formation of the 5‐vinylpyrimidine product.
Cyclization of 1‐substituted‐3‐thiosemicarbazides to triazole derivatives under alkaline conditions
Authors: Altland Henry W. , Graham Patricia A.
Published: April 2009

Under both weakly and strongly alkaline conditions, 1‐alkyl‐2,5‐dithiobiureas (1‐alkyl‐thiocarbamoyl‐3‐thiosemicarbazides) form 4‐alkyl‐5‐amino‐1,2,4‐triazoline‐3‐thiones and 4‐alkyl‐1,2,4‐triazolidine‐3,5‐dithiones in varying proportions. 1‐Alkoxythiocarbonyl‐3‐thiosemicarbazides expel hydrogen sulfide under weakly basic conditions to form the corresponding 5‐alkoxy‐1,2,4‐triazoline‐3‐thiones. In a strongly alkaline environment, however, these alkoxy‐thiocarbonyl thiosemicarbazides eliminate alcohol to form the appropriate 1,2,4‐triazolidine‐3,5‐dithiones. 1‐Alkoxycarbonyl‐3‐thiosemicarbazides eliminate alcohol in both weakly and strongly basic media to give 5‐thiono‐1,2,4‐triazolidine‐3‐ones. Cyclization mechanisms of these thiosemicarbazides are postulated.
Aromatic systems with 10 π electrons derived from 3a‐azapentalene. XXVIII. Electronic and molecular structure of the pyrazolo[1,5‐d]tetrazole system
Authors: Alcalde Ermitas , Claramunt Rosa Maria , Elguero José , Huber Carol P. Saunderson
Published: April 2009

The molecular structure of 1,6‐dimethyl‐7‐ethoxycarbonylpyrazolo[1,5‐d]tetrazole, a 3a‐azapentalene derivative having only nitrogens as ring heteroatoms, has been determined by X‐ray dif‐raction. The compound crystallizes in the space group P21/a with four molecules in a unit cell of dimensions a = 10.184, b = 28.827, c = 4,090 Å, β = 123.37°. The structure, which was solved by direct methods and refined to a final value of R = 0.039, shows a clear difference in bond localization in the two fused rings, in agreement with CNDO/2 calculations. The position of the N‐methyl group corroborates an empirical rule based on pmr.
Preparation of 5‐substituted‐ and 3,5‐disubstituted‐s‐triazolo[4,3‐a]pyridines
Authors: Schneller S. W. , Bartholomew D. G.
Published: April 2009

Cyclization of N‐acyl‐N′‐(6‐chloropyrid‐2‐yl)hydrazines (2a‐2e) with phosphorus oxychloride has produced several 5‐chloro‐s‐triazolo[4,3‐a]pyridines (3a‐3e). Nucleophilic displacement of the chlorosubstituent of 5‐chloro‐s‐triazolo[4,3‐a]pyridine (3a) availed the 5‐ethoxy (4a) and 5‐thioethoxy (4b) derivatives and di(s‐triazolo[4,3‐a]pyrid‐5‐yl)sulfide (8) while reaction of 5‐ethylsulfonyl‐s‐triazolo[4,3‐a]pyridine (4d) with potassium hydroxide yielded the 5‐hydroxy/5‐one system (4c or 6). Further reaction of 3a with bromine to give 3‐bromo‐5‐chloro‐s‐triazolo‐[4,3‐a]pyridine (3g) has provided the corresponding 3‐cyano‐ and 3‐carboxamido‐5‐chloro‐s‐triazolo[4,3‐a]pyridine derivatives (3h and 3i). Treatment of 6‐chloro‐2‐hydrazinopyridine (1) with cyanogen bromide has provided 3‐amino‐5‐chloro‐s‐triazolo[4,3‐a]pyridine (3f) which, with bromoacetaldehyde dimethyl acetal, transformed into 7‐chloroimidazo[1,2‐b]‐s‐triazolo[4,3‐a]‐pyridine (7). Finally, attempts at cyclizing N‐oxalyl‐N′‐(6‐chloropyrid‐2‐yl)hydrazine derivatives (2g‐2i) with intentions of preparing various 3‐acyl‐5‐chloro‐s‐triazolo[4,3‐a]pyridines for entry into other 3,5‐disubstituted systems were unsuccessful.
The insertion and extrusion of heterosulfur bridges. VIII. Dibenzothiophene from biphenyl and derivatives
Authors: Klemm L. H. , Karchesy Joseph J.
Published: April 2009

Sulfur bridging of biphenyl (4), 4‐methylbiphenyl, and the biphenylthiol isomers (7) to yield dibenzothiophene (3) is effected by means of hydrogen sulfide, benzene (solvent), and a sulfided cobaltous oxide‐molybdic oxide‐alumina (CMA‐1) catalyst at 450° in a flow system. Alumina also catalyzes a number of these transformations. The possibility that compounds 7 (especially the 2‐isomer) are intermediates in the conversion 4 → 3 is noted.
Chemistry of the phenoxathiins IV. Synthesis of 9‐substituted 1 ‐azaphenoxathiins
Authors: Martin Gary K. , Turley James C.
Published: April 2009

In an extension of recently reported syntheses of the I‐azaphenoxathiin nucleus as well as several 7‐substituted analogs, the synthesis of several 9‐substituted members of this series is now reported. In addition, the first 13C‐nmr spectral evidence of an interaction between a sulfur atom and the oxygen of an ortho‐nilro group which has been previously observed only in X‐ray erystallographic studies is also described. The possible consequences of this interaction on the reaction pathway leading to the cyclization of the 9‐substituted J‐azaphenoxathiin nucleus is also presented.
Studies on pyrazines. 4.. The synthesis of 2‐hydroxy‐6‐phenylpyrazine and its derivatives
Authors: Sato Nobuhiro
Published: April 2009

This report describes a new method for the preparation of 2‐hydroxy‐6‐phenylpyrazine (1). Amino acetal 5 was converted to glycyl amino acetal 7 by two steps in excellent yield. Cycliza‐tion of 7 to 1 was accomplished in 33% yield by refluxing in acetic acid followed by oxidation with manganese dioxide. Compound 1 was also prepared by hydrolysis of amino‐ and methoxy‐pyrazines 3 and 15, derived from 2‐hydroxy‐5‐phenylpyrazine (2) and the 2‐amino homologue 4, respectively, and by decarboxylation of 2‐hydroxy‐5‐phenylpyrazinecarboxylic acid (19).
The synthesis and ring opening of N‐substituted‐2‐oxo‐6‐azaspiro[2,5] octanes
Authors: Popp Frank D. , Watts Raymond F.
Published: April 2009

N‐Substituted‐4‐piperidones have been reacted with trimethyl sulfoxonium iodide to give the title compounds. These undergo ring opening with lithium aluminum hydride‐aluminum chloride to give piperidine‐4‐methanols which were converted to the chloromethylpiperidines.
Chemistry of adamantane. Part XI 1,2‐Disubstituted adamantanes. Synthesis and reactions of adamantano[2,1‐b]‐ and protoadamantano‐[4,5‐b] [1,5]benzodiazepines
Authors: Chakrabarti Jiban K. , Hotten Terrence M. , Tapper David E.
Published: April 2009

The synthesis and reactions of adamantano[2,1‐b]‐and protoadamantano[4,5‐b] [ 1,5]benzo‐diazepines are described. 12,13‐Dihydro‐1 1aH‐protoadamantano[4,5‐b ] [ 1,5]benzodiazepin‐12‐one (15) rearranged to 2,3‐dihydro‐l‐(protoadamant‐4‐en‐4‐yl)benzimidazol‐2‐one (22). This rearrangement does not proceed with 2‐fluoro‐5,5a,12,13‐tetrahydroadamantano[2,1‐b][ 1,5]‐benzodiazepin‐12‐one (2c) under similar conditions due to its inability to form an olefinic bond at C5a. A convenient method for the α‐carboxylation of ketones using lithium düsopropylamide is also described.
Chemistry of the phenoxathiins V. Correlation of the crystal and molecular structure with pharmacologic activity associated with 7‐ and 8‐chloro‐l‐azaphenoxathiin
Authors: Martin Gary E. , Turley James C. , Korp James D. , Bernal Ivan
Published: April 2009

The crystal and molecular structure of the 7‐ and 8‐chloro analogs of the 1‐azaphenoxathiin system are described. In contrast to previous compounds possessing antipsychotic type activity, the title compounds are both nearly planar, and demonstrate significant substituent location sensitivity, with the 7‐chloro analog exhibiting significant biologic activity while the 8‐chloro isomer is nearly devoid of activity. The relationship of these compounds to the isosterically related phenothiazines in terms of design and molecular geometry considerations is also described.
Un nouvel hétérocycle telluré: le benzisotellurazole‐1,2. 2. Structure cristalline et moléculaire du benzisoselenazole‐1,2 et du benzisotellurazole‐1,2
Authors: Campsteyn Henri , Dupont Léon , Lamotte‐Brasseur Josette , Vermeire Marcel
Published: April 2009

La détermination de la structure cristalline du benzisoselenazole‐1,2 et du benzisotellurazole‐1,2 a permis d'expliquer les proprietes physiques inattendues (point de fusion et solubilité) du dernier composé. Les anomalies observées résultent de l'existence, dans I'empilement du dérivé telluré, de liaisons intermoléculaires Te … N extrěmement courtes (2.4 Å).
Réaction d'horner‐wittig: Synthése de vinylsulfones à partir d'aldéhydes et de cétones hétérocycliques
Authors: Fillion Houda , Péra Marie‐Hélene , Rappa Jean‐Luc , Luu‐Duc Cuong
Published: April 2009

Des vinylsulfones ont été obtenues par réaction de Horner et Wittig entre le carbanion d'un diéthylméthyl‐sulfonométhyl‐phosphonate et un aldéhyde ou une eétone hétérocyclique dans le tetrahydrofuranne. La réactivité des cétones dépend de leur structure et en particulicr de la nature des substituants de l'hétcrocyclc. Les sulfones α, β ethyleniques obtenues à partir des aldéhydes sont des stéreoisomères E; ceux obtenus à partir des cétones sont soit de configuration E, soit des melanges d'isomères E et Z. Leur structure a été déterminée par spectroscopie en rmn.
Reactions of acetylenic ketones with methyl α‐naphthylacetate. A synthesis of l‐amino‐2‐pyridone derivatives
Authors: Al‐Farkh Y. A. , Al‐Hajjar F. H. , El‐Rayyes N. R. , Hamoud H. S.
Published: April 2009

Reactions of acetylenic ketones (Ia‐f) with methyl α‐naphthylacetate in the presence of sodium methoxide gave the corresponding 6‐aryl‐3‐α‐naphthyl‐4‐phenyl‐2‐pyrones (IIa‐f) which upon refluxing with hydrazine hydrate in ethanol gave the corresponding 1‐amino‐2‐pyridone derivatives (VIa‐f).

The structure of the products was established by chemical and spectroscopic evidence.
The insertion and extrusion of heterosulfur bridges. IX: Sulfur bridging in 2‐phenylnaphthalene
Authors: Klemm L. H. , Karchesy Joseph J. , Lawrence Ross F.
Published: April 2009

Sulfur bridging of 2‐phenylnaphlhalene (3) to form benzo[b ]naphtho[2,1‐d]thiophene (5) (main product) and the isomeric benzo[b]naphtho[2,3‐d]thiophene (4) is effected by means of hydrogen sulfide, benzene (solvent), and a sulfided cobaltous oxide‐molybdic oxide‐alumina (CMA‐1) catalyst at 450–630° in a flow system (maximum yield 33% at 500°). The low yield is ascribed to decompositions of both 4 and 5 under reaction conditions.
Mass spectral fragmentation patterns of heterocycles Part 1. 1,4‐Benzodioxans
Authors: Caputo James F. , Martin Arnold R.
Published: April 2009

The mass spectral fragmentation pattern of a series of substituted 1,4‐benzodioxans is reported. The 2,3‐disubstituted compounds show a characteristic fragment peak at mass 121. The 2‐monosubstituted compounds do not show this as fragment peak. The mass peak at 121 has been assigned the empirical formula of C7 H5 O2.
The use of α‐(aryl)‐4‐morpholineacetonitriles (masked acyl anion equivalents) in 1,4‐additions to α,β‐unsaturated esters and nitriles. A versatile synthetic route to 6‐aryl‐3(2H) pyridazinones
Authors: Albright J. D. , Mcevoy F. J. , Moran Daniel B.
Published: April 2009

The use of α‐(substituted‐phenyl)‐4‐morpholineacetonitriles in 1,4‐additions to ethyl acrylate, ethyl crotonate, methyl α‐methylacrylate, acrylonitrile, methylacrylonitrile, crotononitrile and cinnamonitrile was studied. A convenient route to 6‐aryl‐4,5‐dihydro‐3(2H) pyridazinones from aryl aldehydes and heterocyclic aldehydes was developed.
Etude cinétique de l'ouverture du cycle Δ2 imidazoline par hydrolyse basique
Authors: de Savignac Alain , Kabbage Tariq , Dupin Patrice , Calmon Michelle
Published: April 2009

Les cinétiques d'hydrolyse basique de deux Δ2 imidazolines ont été suivies par spectrométrie uv dans la soude et dans le tampon carbonate. Dans les milieux les plus basiques le fait que la vitesse d'hydrolyse soit indépendante du pH est expliqué si l'étape déterminante est l'attaque de l'ion hydroxyle sur la forme protonée du substrat. Dans les milieux moins basiques, un changement d'étape lente intervient, la rupture de l'intermédiaire d'addition de l'ion hydroxyle sur le substrat protoné devenant determinante.
Indolizine derivatives. IX. Preparation of 1‐acylpyrrolo[2,1,5‐cd]indolizines via cycloaddition of 3‐acyloxyindolizines to active ethylenes and acetylenes
Authors: Pohjala Esko K.
Published: April 2009

3‐Indolizinyl acetates and propionates 4 react with ethylenic and acetylenic ketones or carboxylic esters to give 1‐acylpyrrolo[2,1,5‐cd]indolizines 5‐12 in excellent yields.
4,5‐Dihydro‐5‐thioxo‐]H‐tetrazoie‐l‐alkanoic and alkanesulfonic acids and their amide derivatives
Authors: Berges David A. , Chan George W. , Polansky Theodore J. , Taggart John J. , Dunn George L.
Published: April 2009

Homologous 4,5‐dihydro‐5‐thioxo‐1H‐tetrazole‐l‐alkanoic and alkanesulfonic acids were prepared by reaction of sodium azide with methyl (carboxyalkyl)‐ and (sulfoalkyl) carbamodithioates, respectively. 4,5‐Dihydro‐5‐thioxo‐1H‐tetrazole‐i‐alkanamides were derived from the corresponding alkanoic acids by aminolysis of their acid chlorides or imidazolides. Analogous alkane‐sulfonamides were synthesized by the reaction of methyl [[[(1,1‐dimethylethyl) amino]sulfonyl]‐alkyljcarbamodithioates with sodium azide followed by removal of the 1,1‐dimethylethyl group with trifluoroacetic acid.
Rearrangements en série aza‐2 bicyclo[2.2.2] octénique
Authors: Fleury Jean‐Pierre , Desbois Michel
Published: April 2009

Les réarrangements observés sur des dérivés aza‐2 bicyclo[2.2.2]oeténiques substitués sur l'azote par des groupements hydroxytosyloxy ou aeyloxy sont de deux types: une transposition de Wagner‐Meerwein concertée conduisant au système aza‐1 bieyclo[3.2.1]octénique, une coupure du type ré'tro‐aldolisation fournissant une cyclohexénone‐oxime. Ces résultats sont comparés avec ceux observés en série aza‐2 bicyclo[2.2.1]hepténique.
The transformation of saccharin into derivatives of lmidazo[1,2‐b] [1,2]‐benzisothiazole and benzo[g] [1,2,5]thiadiazocine
Authors: Ashby John , Griffiths D. , Paton D.
Published: April 2009

Reaction of 3‐(2‐hydroxyethylamino) benzo[d]isothiazole 1,1‐dioxide (5a) with thionyl chloride gives a mixture of the expected chloroethyl derivative (5h) and the rearranged saccharin 2‐(2‐aminoethyl)‐3‐oxo‐2,3‐dihydrobenzo[d]isothiazole 1,1‐dioxide hydrochloride (6a). Separate treatment of the chloroethyl compound (5h) with dilute alkali gives the expected cyclization product 2,3‐dihydroimidazo[1,2‐b] [1,2] benzisothiazole 5, 5‐dioxide (7a). Acidification of the liquors of the above reaction yields the ring expanded derivative 6‐oxo‐3,4,5,6‐tetrahydro‐[2H]benzo[g][1,2,5]thiadiazocine 1,1‐dioxide (12f), a representative of a new ring‐system. Treatment of the imidazo derivative (7a) with concentrated hydrochloric acid again yields the N‐substituted saccharin (6a) which upon treatment with alkali also produces the thiadiazocine (12f). In contrast, treatment of the imidazo compound (7a) with alkali leads to attack on the sulphonamide function to give 2‐(2‐imidazolin‐2‐yl)benzenesulphonic acid (8). It is suggested that the multitude of chemical interconversions which can be induced within this series of compounds (Scheme II) can only be accounted for if two separate cyclol intermediates are invoked. Related reactions observed with variously substituted derivatives of the starting saccharin derivative (5a) are discussed as are the spectral properties and chemical reactivity of the new compounds prepared.
Synthesis of triazolo[4,3‐d], tetrazolo[1,5‐a] ‐and quinazolino[3,2‐d] [1,4] benzodiazepines
Authors: Madroñero Ramón , Vega Salvador
Published: April 2009

Treatment of 5‐methylmercapto‐1,4‐benzodiazepine (I) with hydrazine hydrate gave the 5‐hydrazino derivative (II, R = H) which, in turn, was conveniently cyclized to the title compounds. Another method for the synthesis of triazolo [4,3‐d] [1,4] benzodiazepines (III) is also described.
Prototropie et synthèses nouvelles dans la série des dihydro‐5,6 hydroxy‐4 pyrones‐2 et pyridones‐2
Authors: Nedjar Bellara , Hamdi Maamar , Périé Jacques , Hérault Valentin
Published: April 2009

La réduction catalytique progressive de la méthyl‐6 hydroxy‐4 pyrone‐2 (1) a mis en evidence quatre étapes et deux dérivés remarquables: l'acide parasorbique (5) actif en biologie, et la méthyl‐6 dihydro‐5,6 hydroxy‐4 pyrone‐2 (2). L'équilibre desmotrope de 2 montre l'importance de la structure énol dont l'hydroxyle est en position 4. L'action des amines primaires sur 2 conduit a des nouvelles dihydro pyridones‐2 N‐arylées 8. Avec la méthylamine on isole une amide intermédiaire 7, après rupture de la liaison 1–2 du cycle. D'autre part, la N‐bromosuccinimide permet les bromations sélectives au site 3 des pyrones et pyridones‐2.
Synthesis of some 3‐EthoxycarbonyI‐5‐hydroxy‐4‐oxo‐2‐pyrroline derivatives from 3(2H)furanones
Authors: Chantegrel Bernard , Gelin Suzanne
Published: April 2009

A number of 3‐ethoxycarbonyl‐5‐hydroxy‐2‐methyl‐5‐or‐1,5‐substituted 4‐oxo‐2‐pyrrolines have been prepared, respectively, by the action of ammonium hydroxide or primary aliphatic amines on 2‐arylidene or 2‐N‐acetyl‐N‐arylaminomethylene‐4‐ethoxycarbonyl‐5‐methyl‐3(2H)furanones. The structures of these prepared compounds have been determined by spectroscopic data and chemical means.
Hétérocyclisations intramoléculaires par réaction d'oxymercuration. IV. Obtention d'alcools par fonctionnalisation des organomercuriques
Authors: Benhamou Marie‐Catherine , Etemad‐Moghadam Guita , Spéziale Vincent , Lattes Armand
Published: April 2009

La réaction de réduction‐oxydation appliquée à des composés organomercuriques hétéro‐cycliques oxygénés permet la fonctionnalisation de ces hétérocycles. Des alcools tétrahydro‐furfuryliques sont ainsi obtenus.
Synthèse et étude physico‐chimique de sulfures, sulfoxydes et sulfones en série thiazolique
Authors: Vernin Gaston , Siv Chhan , Metzger Jacques
Published: April 2009

L'alkylation des Δ‐4‐thiazolines thiones‐2 dans les conditions de la catalyse biphasique conduit aux thioéthers correspondants avec d'excellents rendements. L'action de l'acide méta chloroperbenzoique sur ces sulfures conduit suivant les conditions expérimentales aux sulfoxydes et sulfones correspondantes avec des rendements de 80 à 90%. Le comportement chromatographique et les caractéristiques spectroscopiques de ces composés sont décrits.
Mass spectral fragmentation pattern of heterocycles part I. 1,4‐Benzoxthians
Authors: Caputo James F. , Martin Arnold R.
Published: April 2009

The mass spectral fragmentation pattern of a series of substituted 1,4‐benzoxathians is reported. The di‐substituted compounds show a characteristic fragment peak at mass 137. This same fragmentation peak is also present in some of the monosubstituted compounds. In the former case the 137 mass peak is quite intense and is the base peak for some of the di‐substituted‐1, 4‐benzoxathians. The mass peak at 137 has been assigned the empirical formula of C7H5OS.
Reactions of 2‐nitro‐2‐(4‐pyridyl) propane with nucleophiles. Substitution at tertiary carbon
Authors: Feuer Henry , Doty James K. , Kornblum Nathan
Published: April 2009

The reaction of 2‐nitro‐2‐(4‐pyridyl) propane (I) with lithium 2‐propanenitronate, lithium cyclohexanenitronate, and sodium thiophenoxide affords excellent yields of the C‐alkylation products 2‐nitro‐3‐(4‐pyridyl)‐2,3‐dimethylbutane (II), 2‐(4‐pyridyl)‐2‐(1‐nitrocyclohexyl) propane (V) and 2‐thiophenyl‐2‐(4‐pyridyl) propane (VI), respectively. In contrast, the reaction of compound I with sodium azide does not afford the expected tertiary azide; but instead gives the dimer 2,3‐bis(4‐pyridyl)‐2,3‐dimethylbutane (III), in near quantitative yield. Evidence has been obtained that all of these transformations proceed via electron transfer pathways.
The facile synthesis of some N‐heleroarylacetic esters
Authors: Iwao Masatomo , Kuraishi Tsukasa
Published: April 2009

Methyl and ethyl 2‐quinolylacetate were prepared from quinoline 1‐oxide via acetoacetie ester derivatives. Methyl 2‐quinolyl, 1‐isoquinolyl, 6‐methoxy‐3‐pyridazinyl, 4‐pyridyl and 2‐methyl‐4‐pyridylacetate were synthesized from the corresponding heterocyclic N‐oxides via β‐aminoerotonie ester derivatives.
The reaction of indolizines with tetracyanoethylene
Authors: Ceder Olof , Hall Bengt
Published: April 2009

Tetracyanoethylene (TCNE) reacts with indolizines (1a‐c) to give mixtures of 1‐ and 3‐sub‐stituted tricyanovinylindolizines, respectively. The isomers are identified by nmr spectroscopy. The occurrence of intramolecular charge‐transfer bands in the visible spectra is discussed.
Structural assignments of 2‐aryl and 3‐arylbenzofurans by carbon‐13 nmr
Authors: Kuo George Y. , Ross Stephen T.
Published: April 2009

The 1–3C chemical shifts of 2‐aryl and 3‐arylbenzofurans are discussed. Pairs of isomers can be differentiated based on the chemical shifts of C‐2 in 3‐arylbenzofurans and C‐3 in 2‐arylbenzofurans. A signal near 100 ppm (101 ± 1.7) indicates a 2‐arylbenzofuran and a signal near (141 ± 1.3) indicates a 3‐arylbenzofuran.
4‐Amino‐6‐hydroxy‐1H‐pyrrolo[3,2‐c] pyridine (3,7‐dideazaisoguanine)
Authors: Schneller S. W. , Hosmane R. S.
Published: April 2009

The preparation of 4‐amino‐6‐hydroxy‐1H‐pyrrolo[3,2‐c]pyridine (3,7‐dideazaisoguanine) (1) in five steps from 1H‐pyrrolo[3,2‐c]pyridin‐4,6(5H,7H) dione (3,7‐dideazaxanthine) (2) is described. Furthermore, prolonged treatment of 1 with 10% aqueous sodium carbonate solution is reported to lead to ring opening of the pyridine of 1 resulting in 3‐carboxamidopyrrole‐2‐acetic acid (3).
Addition d'hétérocycles azotés aux alcynes arylés; synthèse de N‐styrylazoles
Authors: Bourgeois Paul , Lucrece Jacqueline , Dunoguès Jacques
Published: April 2009

Les azoles (pyrazoles, imidazoles) se fixent sur la triple liaison du phénylacétylène et du phénylméthylacétylène selon des réactions d'addition, stéréosélectives et stéréospécifiques. Ceci permet la synthèse de divers styrylazoles.
Carbon‐13 nuclear magnetic resonance spectra of methaqualone metabolites
Authors: Brine G. A. , Coleman M. L. , Carroll F. I.
Published: April 2009

Carbon‐13 chemical shifts are reported for methaqualone, seven hydroxylated methaqualone metabolites, and four acetate derivatives. The signals are assigned on the basis of chemical shift theory, SFORD multiplicities, signal intensities, and comparisons with model compounds.
Aporphines 24. The synthesis of N‐alkylderivatives of bulbocapnine and isoeorydine
Authors: Elmaleh David R. , Granchelli Felix E. , Neumeyer John L.
Published: April 2009

The synthesis of three new racemic aporphine alkaloids (1b, 1c and 2) is reported and these alkaloids are fully characterized. The method of synthesis involved either a Bischler‐Napieralski‐Psehorr sequence or a Reissert alkylation‐Pschorr cyclization route. The Pschorr cyclization also gave the morphinandienones 7a and 7b, respectively.
[3+2] Cycloaddition nach addition von allylalkohol und allylaminen an 5‐diazourazile
Authors: Romani Sigrun , Schönholzer P. , Klötzer W.
Published: April 2009

The non‐isolable allylalcohol adduct 2c of 5‐diazouracil 1 undergoes intramolecular [3+2] cycloaddition to afford the tricyclic pyrazolofuropyrimidine 3. In a similar way the reaction of the 5‐diazouracils 2, 2a and 2d with allylamine and diallylamine proceeds via the 6‐amino‐adducts to provide the tricyclic pyrazolopyrrolopyrimidines 5, 5a, 7 and 7a. With allylamine and 2a, the 1,2,3‐triazolederivative 6 is obtained as a byproduct.