bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of 2‐methylcarbamazepine, a new internal standard for chromatographic assays of carbamazepine (tegretol®)
Authors: Patton Jeffrey R. , Dudley Kenneth H.
Published: April 2009

The synthesis of 2‐methyl‐5H‐dibenz[b,f]azepine‐5‐carboxamide (2‐methylcarbamazepine, 2‐MCBZ, 8), a promising internal standard for chromatographic assays of the antiepileptic agent carbamazepine (CBZ, 1), is described. N‐(p‐Tolyl)anthranilic acid (2) was utilized as a starting material for the synthesis of a key compound, 2,9‐dimethylacridine (4), which was converted in two steps to 2‐methyl‐9‐hydroxymethylacridan (6). The acridan 6, in the presence of poly‐phosphoric acid, was ring‐expanded to form 2‐methyl‐5H‐dibenz[b,f]azepine (7), this latter compound being converted by conventional reactions to its 5‐carbamyl derivative, 2‐MCBZ (8).
v‐triazolines. XI . Rearrangement of 1‐aryl‐4,5‐diamino‐4,5‐dihydro‐v‐triazoles
Authors: Citerio L. , Saccarello M. L. , Trimarco P.
Published: April 2009

The reaction of arylazides with 1,2‐diaminoethylenes (1a‐b) or α,β‐diaminostyrenes (1c‐f) gave N‐(1,2‐diaminoethylideneanilines (2a‐e) and N‐(1,2‐diamino‐2‐phenylethylidene)anilines (2g‐i), respectively. These amidine derivatives are formed through the rearrangement of unstable 1‐aryl‐4,5‐diamino‐v‐triazolines. The regiospecificity of the cycloaddition reaction has been elucidated on the basis of the products obtained.
Nuclear magnetic resonance data of pyrido[2,3‐B] pyrazines and their σ‐adducts with amide ion and water
Authors: Nagel A. , Van Der Plas H. C. , Geurtsen G. , Van Veldhuizen A.
Published: April 2009

13C nmr spectral data of the parent substance pyrido[2,3‐b]pyrazine and several of its derivatives (containing one or more chloro, amino, oxo, bromo, fluoro, phenyl, methyl, hydrazino or t‐butyl substituents) are reported. The 13C nmr spectrum of the parent substance has been assigned conclusively by 13C‐labelling. Additionally we proved, the existence of anionic 1:1 σ‐adducls i.e., 3‐amino‐3,4‐dihydropyrido[2,3‐b]pyrazine, the formation of 3‐amino‐2‐t‐butyl‐6‐chloro‐3,4‐dihydropyrido[2,3‐b]pyrazinide ion and by 1H nmr spectroscopy 2‐amino‐1,2‐dihydro‐3‐phenylpyrido[2,3‐b]pyrazinide ion. The 13C nmr data of the cation of the dihydrale 2,3‐dihydroxy‐1,2,3,4‐tetrahydropyrido[2,3‐b]pyrazine, present in a solution of the parent compound in N hydrochloric acid, are given.
Carboxylic n,N‐diphenylcarbamic anhydrides. New acylating agents
Authors: Shepard Kenneth L. , Halczenko Wasyl
Published: April 2009

Carboxylic N,N‐diphenylcarbamic anhydrides have been isolated from the reaction of carboxylate salts with 1‐(N,N‐dipheriylcarbamoyl)pyridinium chloride in aqueous or ethanolic solution. These anhydrides have been shown to be stable, crystalline derivatives and to be very reactive in acylation reactions.

A comparison of pyrazinecarboxylic acid derivatives demonstrated these products to be more reactive than cyanomethyl esters or the so‐called Woodward's esters, acyloxyacrylamides.
Sels d'aziridinium stables c‐fonctionnalisés II: Stéréochimie de la quaternisation, synthèses stérèodirigées de composés n‐trideutériométhylés et attribution de leurs configurations relatives par el'fet overhauser nucléaire
Authors: Rivoirard Eve‐Marie , Raret Paul , Boucherle André , Gey Claude , Pierre Jean‐Louis
Published: April 2009

Diverses aziridines C‐fonetionnalisées N‐méthylées et N‐éthylées ou N‐trideutériométhylées, de configuration a l'azote déterminée, sont quaternisées a différentes temperatures respectivement par le fluorosulfate de méthyle et le fluorosulfate de méthyle‐d3. Les configurations des ions aziridiniums épimères formés sont établies par effet Overhauser nucléaire. La stéréochimie de la reaction est discutée.
The preparation and stereochemistry of 1‐chloroethyl‐4‐methyl‐6,7‐dimethoxyisochroman
Authors: Mccall John M. , Tenbrink Ruth E. , Kamdar Bharat V. , Chidester Constance
Published: April 2009

The boron trifluoride catalyzed reaction of 2‐methyl‐2‐(3,4‐dimethoxypbenyl)ethanol and chloropropionaldehyde diethyl acetal yields a mixture of cis and trans 1‐ehloroethyl‐4‐methyl‐6,7‐dimethoxyisochroman. The structure of the trans compound was established by X‐ray analysis. The trans compound equilibrates to a mixture of the cis and trans when exposed to boron trifluoride catalyst.
Reaction of hydrazine with aryl and heterocyclic selenoamides and alkylselenone esters. Synthesis of 2,5‐diaryl and diheteroeyclic‐1,3,4‐selenodiazoles and dialkylselenone ester‐hydrazones
Authors: Cohen Victor Israel
Published: April 2009

Hydrazine reacted with alkylselenone esters to give dialkylselenone ester‐hydrazones. Reaction of selenoamides with the same reagent led to 2,5‐disubslituled‐1,3,4‐selenodiazoles.
General synthesis of 1a,7b‐dihydro‐1H‐cyclopropa[c]cinnolines with electron‐withdrawing substituents in the 1a‐position
Authors: Garanti Luisa , Zecchi Gaetano
Published: April 2009

2‐Vinylphenylhydrazonyl chlorides (4) react with triethylamine in boiling benzene to afford the title compounds (6) in 54–72% yield, probably through nitrile imine intermediates (5).
Sulphur heterocycles from thiodiacetonitrile and sulphonyldiacetonitrilc
Authors: Crombie D. A. , Kiely J. R. , Ryan C. J.
Published: April 2009

Thiodiacetonitrile reacted with α‐diketones to form 5‐cyano‐2‐thiophenecarboxamides and with α‐keto esters to give 3‐hydroxy‐2,5‐thiophenedicarbonitriles. Sulphonyldiacclonitrile condensed with α,β‐unsaturated ketones to give 6‐cyano‐3,4‐dihydro‐1,1‐dioxo‐2H‐thiopyran‐2‐carboxamides.
Synthesis and reaction of 2,7‐dimethylpyrrolo[1,2‐A]quinoline with electrophilic reagents
Authors: Kuo Hsien‐Saw , Yoshina Shigetaka , Tung Yih‐Chih
Published: April 2009

2,7‐Dimethylpyrrolo[1,2‐a]quinoline (1) was synthesized from 2,6‐dimethylquinoline and bromoaeetone via a Tsebitsehibabin reaction. The electrophilic substitution reactions of I, namely, nitrosation, acylation, diazonium coupling, formylation, bromination, and nitration were studied.
One‐step synthesis of N‐[(methylthio)methyl]imidazole and related heterocyclic derivatives via a fummerer rearrangement
Authors: Janzen A. F. , Lypka G. N. , Wasylishen R. E.
Published: April 2009

N‐[(Methylthio)methyl]imidazole may be prepared from dimethylsulfoxide and N‐(trimethylsilyl)imidazole or N‐(t‐butyldimethylsilyl)imidazole at elevated temperatures via a Purnmerer rearrangement. The product was characterized by elemental analysis, mass spectrometry and proton and carbon nmr. Preliminary experiments show that corresponding derivatives of 2‐methylimidazole, pyrazole, triazole and benzimidazole may also be prepared in an analogous manner.
3(2H)Furanone derivatives. Ring‐chain tautomerism in the 1,3,4,6‐tetraketone series
Authors: Poje M. , Balenovic K.
Published: April 2009

Ring‐chain tautomeric equilibria in the 1,3,4,6‐tetraketone series 1 have been examined and the identification of the chain‐form 2 and hydroxyfuranone 3 has been accomplished from 1H‐nmr spectra; the relative contribution of the two depends on the structure and also on the solvent. Conversions of 1 into 3(2H)furanones 4 and 5 involving the cyclic tautomer 3 are described.
Synthesis of substituted 2‐methyl‐3‐(3,4‐dimethoxy/dihydroxyphenylethyl)4‐quinazolones as possible antiparkinson drugs
Authors: Parmar Surendra S. , Singh Shiva P.
Published: April 2009

Several substituted 2‐methyl‐3‐(3,4‐dimethoxy/dihydroxyphenylethyl)‐4‐quinazolones were synthesized as possible antiparkinsonism agents. The structure of these compounds were confirmed by their elemental and spectral analysis.
Nitrogen bridgehead compounds. IX. Synthesis and reactions of 2,3‐disubstituted pyrido[1,2‐a]pyrimidin‐4‐ones
Authors: Fülöp F. , Hermecz I. , Mészáros Z. , Dombi Gy. , Bernáth G.
Published: April 2009

A series of 4H‐pyrido[1,2‐a]pyrimidin‐4‐ones was prepared by the cyclization of substituted 2‐aminopyridines with βketocarboxylic esters in polyphosphoric acid or in mixtures of the latter with phosphoryl chloride. Catalytic hydrogenation (over palladium on charcoal or Raney nickel) of the products afforded the corresponding 6,7,8,9‐tetrahydropyridopyrimidinones. Thermal treatment of the 6‐substituted derivatives gave 1,8‐naphthyridin‐4‐ones in high yields. Oxo to thio exchange was successful only with substrates unsubstituted at C‐6.
Reaction of nitrenes with strained olefins. Preparation and reactions of some 6‐azabicyclo[3.1.0]hexanes
Authors: Meyer G. Richard , Kellert Cheryl A. , Ebert Robert W.
Published: April 2009

A number of examples of the 6‐azabicycIo[3.1.0]hexane ring system have been prepared by the oxidation of N‐aminophthalimide or 3‐amino‐2‐methyl‐4‐quinazoIone with lead tetraacetate in the presence of variously substituted cyclopentenes.

Thus, 6‐phthalimidyl‐6‐azabicyclo[3.1.0]hexane, dimethy 1–6‐phthalimidyl‐6‐azabicyclo[3.1.0]‐hexane‐1,5‐dicarboxylate, 2,3‐benzo‐6‐phthalimidyl‐6‐azabicycIo[3.1.0]hexane and N‐3‐(2‐methyl‐4‐quinazolyl)‐6‐azabicyclo [3.1.0]hexane were prepared for the first time. All of the new compounds were found to be stable in refluxing carbon tetrachloride and chlorobenzene. Refluxing 6‐phthalimidyl‐6‐azabieyclo[3,1.0]hexane in acetic acid for 24 hours resulted in quantitative rearrangement to a phthalohydrazide, 8.
Reactivity studies of S‐methylthiophenium tetrafluoroborates
Authors: Horak Vaclav , Ee Khoo Lian , Párkányi Cyril
Published: April 2009

The polarographic behavior of four S‐methylthiophenium tetrafluoroborates, I‐IV, has been investigated in Britton‐Robinson aqueous buffers. The compounds under study were the S‐methylbenzo[b]thiophenium (I), S‐methylnaphtho[2,3‐b]thiophenium (II), S‐methyldibenzothiophenium (III), and S‐methylnaphtho[2,1‐b]thiophenium (IV) tetrafluoroborates which were obtained from the parent sulfur heterocycles by their reaction with methyl iodide and silver tetrafluoroborate in 1,2‐dichloroethane, II and IV being new compounds. Compounds I‐IV give two one‐electron reduction waves and the more positive wave appears to be associated with an electron transfer from the electrode to the LUMO of the substrate as indicated by the experimental E1/2 vs calculated LUMO values plot (Figure 2). The rates of demethylation of the ions I‐IV with the iodide ion acting as the nucleophile have been determined in the Britton‐Robinson buffer (pH 6)‐acetonitrile solution at 24°. The results of the polarographic study and of the kinetic studies with the iodide ion confirm the high reactivity of S‐methylthiophenium ions which originates in the antiaromatic destabilization of these structures.
The synthesis of benzofuroquinolines. I. Some benzofuro[2,3‐b]quinoline and benzofuro[3,2‐c]quinoline derivatives
Authors: Kawase Yoshiyuki , Yamaguchi Seiji , Maeda Osamu , Hayashi Akemi , Hayashi Ichihiro , Tabata Kazuko , Kondo Masako
Published: April 2009

Benzofuro[2,3‐b]quinoline (Ia) and its 11‐methyl derivative (Ib) were synthesized by demethylcyclization of 3‐(o‐methoxyphenyl)‐1,2‐dihydroquinolin‐2‐ones (VIa,b). Benzofuro[2,3‐b]quinoline‐11‐carboxylic acid (Id) was synthesized by chlorination followed by the action of potassium hydroxide of a lactone (IX) prepared by demethyl‐cyclization of 3‐(o‐methoxyphenyl)‐2‐oxo‐1,2‐dihydroquinoline‐4‐carboxylic acid (VIII). Isomeric benzofuro[3,2‐c]quinoline (Ha) and its 6‐methyl derivative (IIb) were synthesized by demethyl‐cyclization of 3‐(o‐methoxyphenyl)‐1,4‐dihydroquinolin‐4‐ones (XIa,b). Both the methyl derivatives (Ib and IIb) were converted to the carboxylic acids (Id and IId) through condensation with benzaldehyde followed by oxidation. The benzofuroquinolines (Ia,b,d and IIa,b) thus obtained were oxidized to the corresponding N‐oxides (IIIa,b,d and IVa,b).
Bis‐aminoquinolines as potential antimalarial agents and a novel fused ring system, pyrano[3,2‐c:5,6‐c′]diquinoline
Authors: Nasr M. , Burckhalter J. H.
Published: April 2009

3,3′(1,3‐Ethyliminodimethylene)bis(4‐hydroxy‐6‐methoxy‐2‐methyl)quinoline (2c) and related compounds were synthesized. 3,3‐Methylenebis(4‐hydroxy‐6‐methoxy‐2‐methyl)quinoline (5) was prepared and upon treatment with phosphorus oxychloride gave 1,13‐dimethyl‐5,9‐dimethoxy‐14H‐pyrano[3,2‐c:5,6‐c′]diquinoIine (6), a novel ring system.
Alcohols and aluminium alkoxides in the presence of raney nickel as alkylating agents. 1. Alkylation of indoles and pyrroles
Authors: Botta M. , De Angelis F. , Nicoletti R.
Published: April 2009

Indole and 3‐methylindole are completely converted by alcohols into N‐alkyl or N‐isoalkyl derivatives in the presence of aluminium alkoxides and Raney Nickel; 2‐methylindole gives lower yields. Pyrroles suffer N‐ and C‐alkylation but the initially formed N‐alkylpyrroles are reduced into N‐alkylpyrrolidines in the reaction mixtures.

The occurrence of these N‐alkylations is at variance with the C‐alkylation of indoles and pyrroles which takes place by means of alcohols and sodium alkoxides. This suggests that the reaction occurs between the substrate and the reagent both coordinated by aluminium.
Peroxydation du dihydro‐2,3 4H pyranne et du dihydro‐2,3 furanne. Etude de réactivités
Authors: Filliatre C. , Villenave J. J. , Manigand C.
Published: April 2009

La réaction d'un substrat, possédant un atome d'hydrogène labile, avec un hydroperoxyde en presence d'un sel cuivreux permet de synthétiser des peroxydes. L'analyse de ceux obtenus à partir d'hétérocycles oxygénés insaturés montre une réactivité dix fois plus grande pour les hydrogènes allyliques que pour les hydrogènes en α de l'hétéroatome.
Synthesis in the diazasteroid group XI. A convenient route to the 4,8‐diazasteroid system
Authors: Yamazaki Takao , Takahata Hiroki , Matsuura Tomoko , Castle Raymond N.
Published: April 2009

The reaction of 1,6‐naphthyridine 3 with acetic anhydride results in the formation of the 1:1 adduct 4. Upon catalytic hydrogenation followed by acid hydrolysis and esterification, 4 affords 7 as an A‐B steroid ring system synthon in moderate yield. Upon condensation with cyclopentanone and cyclohexanone, 7, gives the 4,8‐diazasteroid system 8 and the D‐homo compound 9, respectively.
Pyrimidones 1. Synthesis of some 1‐substituted‐5‐aryl‐ and (4,5‐diaryl)‐2(1H)pyrimidones
Authors: Coppola Gary M. , Fraser James D. , Hardtmann Goetz E. , Huegi Bruno S. , Kathawala Faizulla G.
Published: April 2009

A series of 1‐substituted‐5‐aryl‐2(1H)pyrimidones has been prepared by a method involving condensation of an appropriate N‐substituted urea with either 2‐aryl‐3‐(dimethylamino)‐acroleins or 2‐arylmalondialdehydes. On biological investigation, several compounds exhibited some antiinflammatory activity.
Alkyl‐ and arylthiation of uracil and indole
Authors: Anzai Kentaro
Published: April 2009

5‐Alkyl‐ or arylthio‐2,4‐pyrimidinediones, 1–8, were prepared from uracil and alkane‐ or arenesulfenyl chlorides. Indole reacted similarly to give the 2,3‐di‐ and 3‐substituted derivatives, 15–19.
Characterization of blocked nucleosides by mass spectrometry. Benzyl derivatives
Authors: Cory H. T. , Yamaizumi K. , Smith David L. , Knowles D. R. , Broom Arthur D. , Mccloskey James A.
Published: April 2009

The mass spectra of eleven model monobenzylated nucleosides were studied using low and high resolution mass spectrometry. Structural assignments to the major ions were made and several decomposition mechanisms proposed, with the goal of establishing the uses and limitations of mass spectrometry for the characterization of benzylaled nucleosides. Mass spectra generally permit determination of the extent and site of benzylation, with particular regard to base vs. sugar substitution, 0–2′ vs. 0–3′ or 0–5′, and in some cases 0–5′ vs. other isomers.
Synthesis of 6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,2,6‐dioxathiazocine 2‐oxides
Authors: Nishiyama Tomihiro , Ido Kiyoshi , Yamada Fukiko
Published: April 2009

Four 6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,2,6‐dioxathiazocine 2‐oxides were synthesized by the reaction of the corresponding N,N‐bis(2‐hydroxyethyl)aniline with thionyl chloride in the presence of triethylamine.
Synthesis of 1‐(N‐piperidinoacetyl)‐4‐arylthiosemicarbazides as possible anticonvulsants
Authors: Misra R. S. , Parmar S. S. , Kishore V. , Ali B. , Gupta T. K.
Published: April 2009

Several 1‐(N‐piperidinoacetyl)‐4‐arylthiosemicarbazides were synthesized from N‐piperidinoacetyl hydrazide, which was obtained by the reaction of hydrazine hydrate with ethyl N‐piperidinoacetate. The anticonvulsant activity of these substituted thiosemicarbazides was reflected by their ability to provide 10–50% protection against pentylenetetrazol‐induced convulsions in mice. All substituted thiosemicarbazides (0.3 mM) inhibited in vitro monoamine oxidase activity of rat brain homogenates and provided 21–86% protection against hypoosmotic hemolysis at a final concentration of 0.1 mM.
Some derivatives of benzoin
Authors: Mendel Arthur , Lillquist Gerald J.
Published: April 2009

Extension of the reaction time of benzoin (I) with anthranilamide (II) gave 2,3,5,6‐tetraphenyl‐pyrazine (IV) in addition to the expected benzamide III. Condensation of I with II in the presence of ammonium acetate or ammonium formate yielded IV, and IV with 4‐quinazolinone (VII), respectively. Reaction of I with ammonium acetate only led to IV and 2,3,5,6‐tetraphenylpyrrole (VIII). When I was heated with 2‐aminothiazole, benzil, desoxybenzoin, and VIII were formed. A mechanism has been extended to explain the formation of IV and VIII.
Nitrogen photochemistry. Cocaine and its model compounds
Authors: Singh S. P. , Kaufman Don , Stenberg Virgil I.
Published: April 2009

The ultraviolet irradiation of the π → π* transition of cocaine, p‐anisoyl‐l‐ecognine methyl ester, p‐toluoyl‐l‐ecognine methyl ester benzoyl tropine and benzoylpseudotropine in methanol using a Corex filter produces the corresponding N‐demethylated products. Formaldehyde is quantitatively produced. 1‐Methyl‐3‐piperidyl benzoate and 1‐methyl‐4‐piperidyl benzoate yield benzoic acid under the same conditions but no demethylated products. Phenylacetyl‐l‐ecognine methyl ester gives no demethylation during irradiaiton. The phosphorescence bands of cocaine and its model compound, methyl benzoate, have been shown to be strongly dependent upon solvent polarity suggesting charge transfer in the triplet state.
Derivatives of indole‐3‐oxyacetic acid
Authors: Galun A. , Kampf A. , Markus A.
Published: April 2009

The synthesis of 1‐benzyl‐2‐methyl‐5‐methoxyindole‐3‐oxyacetic acid (11) and of 1‐benzyl‐2‐methylindole‐3‐oxyacetic acid (17) was undertaken in the course of a study aimed at the preparation of potential anti‐inflammatory agents.
Synthesis of some substituted 3‐alkenyl‐1‐phenylpyrazoles
Authors: Deshayes Christian , Gelin Suzanne
Published: April 2009

The regioselective synthesis of new 3‐alkenyl‐1‐phenylpyrazoles 4 from the reaction of phenylhydrazine with 2,3‐dihydro‐4H‐pyran‐4‐ones 1 is described.
5,6‐Dimethylbenz[c]acridine functionalized in the 7‐position
Authors: Cromwell Norman H. , Pokorny David J. , Loerch Robert , Kasperbauer Jan
Published: April 2009

5,6‐Dimethylbenz[c]acridines, functionalized in the 7‐position by the carboxy, carbomethoxy, carboxamido, N‐ethylcarboxamido, acetyl, cyano, chloro, methoxy or amino group are reported for the first time. Also various related 5,5‐dimethyl‐5,6‐dihydrobenz[c]acridines including the 7‐carbomethoxy, 6‐hydroxy‐7‐carboxy, 6‐bromo‐7‐carbomethoxy, 6‐methoxy‐7‐carboxy, 6‐methoxy‐7‐carbomethoxy, and 6‐hydroxy‐7‐N‐ethylcarboxamido derivatives which serve as precursors to the completely aromatized 5,6‐dimethylbenz[c]acridines are also reported for the first time.
Synthesis of acetylenic β‐diketones and their conversion into 4H‐pyran‐4‐ones, pyrazoles, and 1‐hydroxy‐4‐pyridones
Authors: El‐Kholy Ibrahim El‐Sayed , Marei Mohamed Gaber , Mishrikey Morcos Michael
Published: April 2009

A simple method for the synthesis of acetylenic β‐diketones is described. They can be cyclized to the corresponding 4H‐pyran‐4‐ones with acids. Their reaction with hydrazine hydrate gave pyrazole derivatives isomeric with those obtained from 4H‐pyran‐4‐ones. With hydroxyl‐amine hydrochloride in ethanol, 1‐hydroxy‐4‐pyridones are formed.
Conformation of 7‐chloro‐5‐phenyl‐d5 −3(S)‐methyl‐dihydro‐1,4‐benzodiazepin‐2‐one in solution
Authors: Šunjić V. , Lisini A. , Sega A. , Kovač T. , Kajfež F. , Ruščić B.
Published: April 2009

7‐Chloro‐5‐phenyl‐d5‐3(S)‐methyldihydro‐1,4‐benzodiazepin‐2‐one (1a) was synthesized and its conformation in solution determined using a computer assisted LIS‐NMR method. It was found, with Fr(fod)‐d27 as a shift reagent, that a lanthanide coordinates to a carbonyl oxygen at a 2.02 Å distance (bond angle 158.07°, torsional angle 39.53°), while the substrate 1a adopts an expected quasi‐boat conformation with a C(3)‐methyl group exposed in a quasi‐equatorial position.
Steroidal aminothiazoles
Authors: Catsoulacos Panayotis , Kallias Dimitrios
Published: April 2009

The treatment of 16α‐bromo‐17‐ketosteroids and 2‐bromo‐3‐ketosteroids with thiourea in dimethylformamide give the corresponding 2′‐formamidothiazolosteroids.

The resulting 2′‐formamidothiazoles were identical with those obtained in a similar reaction from 17β‐bromo‐16α,17α‐oxidoandrostane with thiourea. Hydrolysis of the 2′‐formamido‐thiazolosteroids led to the corresponding 2′‐aminothiazoles, which also resulted from the interaction of bromoketones and thiourea in isopropanol.

The title compounds prepared were substantiated by examination of infrared, ultraviolet, mass and nuclear magnetic resonance spectra.
Synthèse de 1H‐pyrazolo[3,4‐b] pyridines et de pyrazolo[1,5‐a] pyrimidines
Authors: Van Haverbeke Y. , Maquestiau A. , Vanden Eynde J. J.
Published: April 2009

La réaction entre une aminopyrazolone et un dérivé β‐dicarbonylé est étudiée. L'orientation de la cyclocondensation dépend de la nature de chacun des précurseurs.
Coumarins via the wittig reaction. Synthesis of methoxsalen‐5‐14C
Authors: Liu Yu‐Ying , Thom Edna , Liebman Arnold A.
Published: April 2009

A new and improved synthesis of methoxsalen (3) has been developed for the preparation of specifically carbon‐14 labelled 3. Introduction of the label by a Gattermann reaction on 6‐hydroxy‐7‐methoxycoumaran (1) followed by dehydrogenation provides an intermediate 6 which, on reaction with carbethoxymethylenetriphenylphosphorane (8) and heat inversion, provides the title compound in overall yields of up to 50%. By these procedures, 3 has been prepared 14C labelled at C‐5. Alternatively, 3 may be prepared from 6 and ethyl cyanoacetate in lower overall chemical yield but in potentially higher radiochemical yield if labelling at C‐6 or C‐7 is required since the Wittig process utilizes an excess of phosphorane.
The chemistry of 2H‐3,1‐benzoxazine‐2,4(1H)dione (isatoic anhydride) 4. Synthesis of 2‐imino‐3‐indolinones
Authors: Coppola Gary M.
Published: April 2009

The reaction of isatoic anhydrides with potassium cyanide to form 2‐imino‐3‐indolinones (2) is described. Acidic hydrolysis of 2 furnishes the corresponding isatins.
The chemistry of 2H‐3,1‐benzoxazine‐2,4‐(1H)dione (isatoic anhydride) 5. Synthesis of the [1]benzopyrano[3,2‐c]quinoline ring system
Authors: Coppola Gary M. , Hardtmann Goetz E.
Published: April 2009

The reaction of isatoic anhydrides with the anion derived from ethyl o‐fluorobenzoylacetate to furnish [1]benzopyrano‐[3,2‐c]quinolines is described. An analogous reaction with 3‐azaisatoic anhydride furnishes 1b, or with tricyclic anhydride 3, system 4 is isolated. Spectral data is also discussed.
Synthesis of a new bridgehead nitrogen heterocyclic system. Pyrrolo [2,1‐f]‐1,2,4‐triazine derivatives
Authors: Migliara Onofrio , Petruso Salvatore , Sprio Vincenzo
Published: April 2009

1‐Ureidopyrroles of type 6a,b prepared by the general method previously described (2), readily cyclized under basic conditions giving pyrrolo [2,1‐f]‐1,2,4‐triazine‐2,4(1H, 3H)dione derivatives.
Study of some reactions of ethyl 4‐phenyl‐3‐benzoyl‐2‐pyrazoline‐5‐carboxylate
Authors: El‐Kholy Ibrahim El‐Sayed , Mishrikey Morcos Michael , Euid‐Alla Hassan Moslafa , Nashed Mina Anis
Published: April 2009

Several reactions of the pyrazoline 1a were investigated. With bromine water, potassium permanganate, hydrogen peroxide, or potassium hydroxide, different pyrazole derivatives were formed. While the reaction with hydroxylamine or some hydrazines gave the corresponding pyrazoline Schiff bases, with aroylhydrazines, pyrazole Schiff bases were formed.
The crystal and molecular structures of 1‐(P‐bromophenyl)‐5‐bromopyridazine‐3,6‐dione and 1‐(p‐bromophenyl)‐4‐diethylaminopyridazine‐3,6‐dione
Authors: Stam C. , Zwinselman J. J. , Van Der Ptas H. C. , Baloniak S.
Published: April 2009

The structure of 1‐(p‐bromophenyI)‐5‐bromopyridazine‐3,6‐dione was unequivocally established by means of an X‐ray crystal structure determination. By the same means its reaction product with diethylamine was proved to be 1‐(p‐bromophenyl)‐4‐diethylaminopyridazine‐3,6‐dione.
Syntheses of some azinylhydroxylamines
Authors: Tomažič A. , Tišler M. , Stanovnik B.
Published: April 2009

Syntheses of some hydroxylaminoazines and hydroxamic acids were investigated. For direct displacement with hydroxylamine a good leaving group, activated by other substituents, must be present.
Hydroxymethylation and cyanoethylation of nitroimidazoles
Authors: Sehgal Raj K. , Agrawal Krishna C.
Published: April 2009

A series of nitroimidazoles were subjected to hydroxymethylations under a variety of conditions. Hydroxymethylation of 1‐(2‐hydroxyethyl), 1‐(2‐acetoxyethyl), and 1‐(2‐chloroethyl) substituted 5‐nitroimidazoles with paraformaldehyde in dimethyl sulfoxide yielded the respective 2‐hydroxymethyl analogs (5–7). However, attempts to hydroxymethylate 1‐(2‐hydroxyethyl), 1‐(2‐acetoxyethyl), 1‐(2‐cyanoethyl) substituted 4‐nitroimidazoles and 1‐(2‐hydroxyethyl)‐2‐nitroimidazole were unsuccessful. Treatment of 1‐(2‐acetoxyethyl)‐5‐nitro‐2‐imidazolecar‐baldehyde(10) with hydroxylamine‐O‐sulfonic acid afforded a mixture of corresponding 2‐carbonitrile (12) and 2‐(N‐hydroxy)carboximidamide (13). Hydrolysis of 10 with ethanolic hydrochloric acid yielded 8‐ethoxy‐5,6‐dihydro‐3‐nitro‐8H‐imidazo[2,1‐c] [1,4]oxazine (11) which, on subsequent reaction with hydroxylamine‐O‐sulfonic acid, afforded 1‐(2‐hydroxyethyl)‐5‐nitroimidazole‐2‐(N‐hydroxy)carboximidamide (15). Reaction of 4(5)‐nitroimidazole with chloropropionitrile produced a mixture of the isomeric 1‐(2‐cyanoethyl) substituted 4‐ and 5‐nitroimidazoles. Treatment of 2,4(5)‐dinitroímidazole with chloropropionitrile afforded a mixture of 4(5)‐chloro‐5(4)‐nitroimidazole and 1‐(2‐cyanoethyl)‐4‐nitro‐5‐chloroimidazoIe. Reaction of nitroimidazoles with acrylonitrile in the presence of Triton B yielded the corresponding 1‐(2‐cyanoethyl) substituted derivatives.
Synthesis of 2,3‐dihydro‐5H‐oxazolo[2,3‐B]quinazolin‐5‐ones
Authors: Peet Norton P. , Anzeveno Peter B.
Published: April 2009

Iodide‐catalyzed ring expansion of 2‐[(1‐aziridinylcarbonyl)amino]benzoic acid methyl ester (2) gave 2,3‐dihydro‐5H‐oxazolo[2,3‐b]quinazolin‐5‐one (3) in quantitative yield. Treatment of the dimethyl analog of 2 (9) with sodium iodide in acetone gave a mixture of the 2,3‐dihydro‐2,2‐dimethyl‐ (10) and 2,3‐dihydro‐3,3‐dimethyl‐5H‐oxazolo[2,3‐b]quinazolin‐5‐ones (11). However, rearrangement of 9 with sulfuric acid produced only 10. Synthesis of 11 by another route for comparison is described, and the known syntheses of 2,3‐dihydro‐5H‐oxazolo[2,3‐b]quinazolin‐5‐ones are reviewed.
Synthesis and antimalarial effects of N,N‐dialkyl‐6‐(substituted phenyl)‐1,2,4,5‐tetrazin‐3‐amines
Authors: Werbel Leslie M. , Mcnamara Dennis J. , Colbry Norman L. , Johnson Judith L. , Degnan Margaret J. , Whitney Barbara
Published: April 2009

The synthesis of a series of N,N‐dialkyl‐6‐(substituted phenyl)‐1,2,4,5‐tetrazin‐3‐amines (IV) by two routes is described. The first route (Scheme I) involved the oxidative cyclization of formazans (II) to 3‐bromo‐6‐(substituted phenyl)‐1,2,4,5‐tetrazines (III), followed by treatment with amines. The second (Scheme II) utilized the treatment of 3‐(methylthio)‐6‐(substituted phenyl)‐1,2,4,5‐tetrazines (VII) with amines to provide the desired products. The intermediate 3‐(methylthio)‐6‐(substituted phenyl)‐1,2,4,5‐tetrazines (VII) were obtained by thiobenzoylation of hydrazinecarbohydrazonothioic acid methyl ester with [[(substituted phenyl)thioxomethyl]thio]‐acetic acids (V) to afford the 1,2‐dihydro‐3‐(methylthio)‐6‐(substituted phenyl)‐1,2,4,5‐tetrazines (VI). Oxidation with bromine in acetic acid provided the desired intermediates. The target 6‐(substituted phenyl)‐1,2,4,5‐tetrazin‐3‐amines (IV) displayed modest antimalarial activity.
Reaction of sulfene and dichloroketene with N,N‐disubstituted 5‐aminomethylene‐1,5,6,7‐tetrahydro‐2‐methyl‐1‐phenylindol‐4‐ones. Synthesis of 1,2‐oxathiino[6,5‐E] indole and of pyrano[2,3‐e] indole derivatives
Authors: Mosti Luisa , Schenone Pietro , Menozzi Giulia
Published: April 2009

The 1,4‐cycloaddition of sulfene to N,N‐disubstituted 5‐aminomethylene‐1,5,6,7‐tetrahydro‐2‐methyl‐1‐phenylindol‐4‐ones afforded N,N‐disubstituted 3,4,5,6‐tetrahydro‐8‐methyl‐7‐phenyl‐7H‐1,2‐oxathiino[6,5‐e]indol‐4‐amine 2,2‐dioxides only in the case of aliphatic N‐substitution. The 1,4‐cycloaddition of dichloroketene occurred normally only in the case of 1,5,6,7‐tetrahydro‐2‐methyl‐1‐phenyl‐5‐piperidinomethyleneindol‐4‐one to give 3,3‐dichloro‐3,4,5,6‐tetrahydro‐8‐methyl‐7‐phenyl‐4‐piperidino‐7H‐pyrano[2,3‐e]indol‐4‐one. Attempted recrystallisation, dehydro‐chlorination or treatment with palladium on carbon of this adduct, as well as reaction of similar enaminoketones with dichloroketene, gave instead the same product, namely 3‐chloro‐8‐methyl‐7‐phenyl‐7H‐pyrano[2,3‐e]indol‐4‐one, as a result of dehydrochlorination, dehydrogenation and subsequent hydrogenolysis of the C‐NR2 bond in the primary adduct.
Carbon‐13 nmr chemical shift‐substituent effect correlations in P‐substituted 5‐benzylidenebarbituric acids and 2‐benzylidene‐1,3‐indanediones
Authors: Robinson Charles N. , Irving Charles C.
Published: April 2009

Excellent correlations have been observed between σ+ constants and the 13C nmr chemical shifts of several of the carbon atoms of 5‐arylidenebarbituric acids and of 2‐arylidene‐1,3‐indanediones.
υ‐Triazolines. Part XIII. Reactions of α‐ketoenamines with toluene‐P‐sulphonylazide
Authors: Pocar Donato , Rossi Luisa Maria , Trimarco Pasqualina
Published: April 2009

Some enamines derived from α‐diketones have been reacted with tosylazide yielding unstable 5‐amino‐υ‐triazolines, which were found to undergo cyeloreversion to diazo compounds and arnidines. In the case of the enamines derived from 4‐aryl‐2,3‐butanediones, a competitive rearrangement to (Z)‐4‐aryl‐4‐arnino‐3‐tosylamino‐3‐butene‐2‐ones was observed.
Tautoméric entre structures α‐aleoxy énaminocétone et β‐céto iminoéther présentée par les pipéridéines résultant de la semihydrogénation d'alcoxy‐2 acyl‐3 pyridines
Authors: Sliwa Henri , Delaunay Luc
Published: April 2009

L'hydrogénation partielle, en présence de palladium ou de platine, d'alcoxy‐2 acyl‐3 pyridines a été réalisée en vue d'étudier la tautoméric des tétrahydropyridines résultantes. La réduction en pipéridéine se produit sélectivement pour les composés bicycliques 2 et 3, tandis que la réduction du groupe carbonyle devient prépondérante dans le cas du dérivé 1 présentant le groupe acyle dans une chaǐne ouverte. Cetle différence de comportement est interprétée à I'aide du concept de contrainte interne (“I‐strain” effect). Alors que les tétrahydropyridines bicycliques 6 et 7 possèdent exclusivement une structure d'α‐alcoxy ènaminocétone, la pipéridéine 5 qui est substituée par des chaǐnes ouvertes existe uniquement sous forme de β‐céto iminoéther, comme le montrenl les études spectrographiques ir et de rmn. L'analyse des interactions susceptibles de se produire entre les doublets libres des hétéroalomes permet de rendre compte du déplacement total des équilibres de tautoméric vers I'une ou I'autre de ces deux structures: dans le cas des dérivés bicycliques, I'interaction destabilisante que présenterait I'iminoéther, fait place au sein de la structure ènaminocétone, à une interaction stabilisante entre le doublet de I'oxygène et la liaison N‐II, sans qu'il y ait accroissement des contraintes stériques.
Charge transfer complexes between iodine and the thioamido entity contained in some pentaatomic rings
Authors: Devillanova Francesco A. , Verani Gaetano
Published: April 2009

Spectrophotometric investigations on the adducts of iodine with pyrrolidine‐2‐thione, 1,3‐oxazolidine‐2‐thione, 1,3‐thiazolidine‐2‐thione and N‐methyl‐1,3‐thiazolidine‐2‐thione have been carried out in carbon tetrachloride and dichloromethane solutions. These complexes show a very intense peak, due to the charge transfer band, and the well known “blue shift” of the visible band of iodine, whereas the analogous shift of the ligand is masked from the solvents. Their thermodynamic and spectral characteristics have been determined and compared with those of the series of 1,3‐imidazolidine‐2‐thione.
Synthesis of new heterocyclic ring systems. Reaction of indolines and hexahydrocarbazole with α,β‐unsaturated acids
Authors: Shankarnarayan V. , Merchant J. R.
Published: April 2009

Reactions of indoline (I), 2‐methylindoline (II) and hexahydrocarbazole (III) with α,β‐unsaturated acids in the presence of polyphosphoric acid have been investigated. Reaction of 1 with acrylic acid afforded two compounds which were identified as 1,2,4,5‐tetrahydro‐6H‐pyrrolo‐[3,2,1‐ij] quinolin‐6‐one (IV) and 2,3,5,6,9,10‐hcxahydro‐1H‐cyclopenta[f lpyrrolo [3,2,1‐ij|‐quinoline‐1,8‐dione (VII). The reaction oi 1 with crotonic acid gave compounds V and VIII, analogous‐to IV and VII. The reaction of II with acrylic acid yielded two compounds VI and IX, whereas with crotonic acid, only X was isolated. With 111, acrylic acid afforded 5,6,8,9,10. 11,8a,11a‐octahydro‐4H‐pyrido[3,2,1‐jk]carbazol‐4‐one (XI) and a compound with a heretofore unknown ring system, viz., 2,3,5,6,7,8,11,12,5a,8a‐decahydro‐1H‐cyclopenta[h] pyrido [3,2,1‐jk |earbazole‐1,10‐dione. The structures of these compounds were deduced on the basis of their spectral and analytical data.
1H nmr structural analysis of azabicyclospirohydantoins
Authors: Trigo G. G. , Gálvez E. , Espada M. , Bernal C.
Published: April 2009

The structure and spatial conformation of 3‐alkyl‐3‐azabicyclo[3.2.1]octane‐8‐spiro‐5′‐hydantoins and 8‐alkyl‐8‐azabicyclo[4.3.1]decane‐10‐spiro‐5‐hydantoins has been determined on the basis of the data from 1H nmr. The chair conformation of the piperidine ring and the presence of only one stereoisomer at the spiro carbon atom are corroborated. All these facts have been confirmed by x‐ray diffraction methods (2).
Condensed benzopyrans. IV. Synthesis of some derivatives of 7H‐ and 9H‐pyrano[3,2‐E]indoles
Authors: Khan Misbahul Ain , De Brito Morley Maria Lúcia
Published: April 2009

The hydrazones derived from coumarin‐6‐ylhydrazine and ethyl 6‐hydrazinochromone‐2‐carboxylate undergo facile indolization to give 3H,7H‐pyrano[3,2‐e]indol‐7‐ones (IIIb‐IIIg) and ethyl 9‐oxo‐3H,9H‐pyrano[3,2‐e]indole‐7‐carboxylates (IVb‐IVd), respectively, in good yields. Compounds IVb‐IVd are derivatives of a new ring system.
Oxidation and acid‐catalyzed cyclization of aldehyde 2‐aminophenylhydrazones. Alternative syntheses for 1,2,4‐benzotriazines and benzimidazoles
Authors: Cerri Riccardo , Roido Alessandro , Sparatore Fabio
Published: April 2009

Aldehyde 2‐aminophenylhydrazones are easily oxidized by air to 3‐substituted 1,2,4‐benzotriazines. In two cases the intermediate 3,4‐dihydro‐1,2,4‐benzotriazines were isolated. In the absence of oxygen, acids catalyze the formation of 2‐substituted benzimidazoles with loss of ammonia. It is suggested that both reactions proceed via 1,2,3,4‐tetrahydro‐1,2,4‐benzotriazines (III), formed by addition of the amino group on the hydrazone double bond. Such cyclic forms (III) predominate over the open chain structures (II) in the cases of aliphatic and arylalkylaldehyde 2‐aminophenylhydrazones, as supported by nmr spectra, while benzaldehyde 2‐aminophenylhydrazone exists mainly or exclusively in the open chain form (II).
Sulfur nitride in organic chemistry. 6. Preparation of 3,4‐disubstituted 1,2,5‐thiadiazoles by the reaction of sulfur nitride with acetylenes
Authors: Mataka Shuntaro , Takahashi Kazufumi , Yamada Yukihiro , Tashiro Masashi
Published: April 2009

The reaction of sulfur nitride (1) with acetylenes (2a‐m) was carried out in refluxing toluene to give 1,2,5‐thiadiazoles (3a‐m) as a major product.
2‐Aminothiazole derivatives. II. Mass spectra of ethyl N‐(2‐thiazolyl)‐malonamates and ethyl 2‐thiazolylaminomethylenemalonates
Authors: Saint‐Ruf G. , Silou T. H.
Published: April 2009

The fragmentation pattern of the title compounds under electron impact are discussed. During fragmentation in the mass spectrometer, these compounds undergo a rare type of rearrangement involving a long distance transfer of hydrogen.
Friedel‐crafts acylalion of 3‐carboxymethylbenzo[B] thiophenes, LIS‐nmr and HOMO study of regioselectivity
Authors: Hannoun M. , Blazević A. , Kolbah D. , Sabljiéa A. , Trinajstić N. , Sega A. , Lisini A. , Kajfež F. , Šunjić V.
Published: April 2009

3‐Carboxymethylbenzo[b] thiophenes give on benzoylation and acetylation, two pairs of isomers, 2/3 and 4/5, respectively. It is determined by the combined nmr spectroscopic analysis (360 MHz and calculated spectra, LIS‐nmr) and HOMO calculations of the electron densities on positively charged 1, that 2 and 4 are 4‐substituted, while 3 and 5 are 6‐substituted isomers.
Nuclear magnetic resonance study of furan‐2‐carbaldehyde N‐alkylimines
Authors: Devi Purabi , Sandhu J. S. , Thyagarajan G.
Published: April 2009

A cmr and pmr study of furan‐2‐carbaldehyde N‐alkylimines is reported.
Synthese du noyau dihydro‐5,6 s‐triazolo[2,3‐d] henzoxazepine‐1,4
Authors: Moskowitz H. , Mignot A. , Miocque M.
Published: April 2009

Un nouveau système hétérocyclique, la méthylène‐5 éthylthio‐2 dihydro‐5,6 s‐triazolo [2,3‐d] henzoxazépine‐1,4, a été preparé par cyclisation du propynyloxyphenyltriazole correspondant. L'attaque nucléophile d'un azote triazolique sur la triple liaison conduit également à trois isornères et notamment à une s‐triazolo [3,2‐d] benzoxazocine.
A simple synthesis of 1‐phenothiazineethanolamines: Potential antimalarials
Authors: Pinto Ângelo C. , Da Silva Rosaly S. , Hollins Richard A.
Published: April 2009

Two routes for the synthesis of the 1‐phenothiazineethanolamine (4) starting from 1,2‐dioxo‐1,2‐dihydropyrrolo[3,2,1‐kl]phenothiazine are described.
The synthesis and photochemistry of 4‐amino‐3‐cyanopyrazole
Authors: Kagan Jacques , Melnick Bennett
Published: April 2009

4‐Amino‐3‐cyanopyrazole (6) had once been considered to be a possible intermediate in the photochemical conversion at 350 nm of diaminomaleonitrile (1) into 4‐amino‐5‐cyanoimidazole (3), a precursor of adenine. The pyrazole was synthesized and irradiated at 350 nm. No isomerization into the imidazole was observed, even when the photolysis was carried out in the presence of an excess of 1, where sensitization by this or one of its photolysis products might have operated. At 254 nm, complete decomposition of 6 was observed, with formation of polymeric products. At 300 nm, 6 underwent isomerization to 3, as well as extensive decomposition. Hydrogen cyanide was probably produced, which reacted with the remaining starting material to yield 7‐aminopyrazolo[4,3‐d]pyrimidine (10), which did not isomerize into adenine under the photolysis conditions. A polymer was also obtained, from which glycine was identified after hydrolysis.
The synthesis and chelation properties of oximes of certain 2‐quinolylmethyl and 2‐phenanthrolylmethyl ketones and of various hydrazones of 2‐acetylquinoline and 2‐acetyl‐1,10‐phenanthroline
Authors: Case Francis H. , Schilt A. A.
Published: April 2009

Certain oximes were prepared from 2‐quinolylmethyl 2‐pyridinyl ketone and 2‐(1,10‐phenanthrolyl)methyl 2‐pyridinyl ketone. Also, the preparation of two series of hydrazones was effected: one from 2‐acetylquinoline and one from 2‐acetyl‐1,10‐phenanthroline. The latter compound and 2‐(2‐quinolyl)‐1,10‐phenanthroline were also synthesized. All the compounds were tested for their metal‐chelation properties.
Nouveaux dérivés tricycliques du benzimidazole
Authors: Guerret Patrick , Langlois Michel
Published: April 2009

Une réaction générale acido catalysée d'hétérocyclisation de céto‐2 (hydroxyéthyl)‐1 benzimidazole en présence d'un alcool ou d'un thiol est décrite. Les méthodes de preparation de nouveaux dérivés amino alcoylés tricycliques du benzimidazole sont données.
[1] Benzofuro[2,3‐d] pyridazines. VI. Etude des reactions de scission des acyltetrahydrobenzofuropyridazones
Authors: Robba Max , De Sevricourt Michel Cugnon , Godard Anne‐Marie
Published: April 2009

Les réactions de scission du cycle pyridazinique des acyltétrahydrobenzofuropyridazones sont réalisables par hydrolyse, alcoolyse ou aminolyse et elles concernent la liaison lactamique‐3,4. Elles conduisent à des dérivés benzofuranniques portant sur le sommet 2 des groupements acide, ester, amide ou hydrazide et sur le sommet 3 des groupements méthylhydrazine éventuelle‐mentacylés. Les réactions de cyclisation effectuées sur l'acide hydrazinométhyl‐3 benzofuranne‐carboxylique‐2 ou sur ses dérivés ainsi que sur le bromométhyl‐3 benzofurannecarboxylate d'éthyle‐2 représentent une nouvelle synthèse des tétrahydrobenzofuropyridazones.
Triazino‐1,2,4‐[4,5‐a] indoles IV. Etude des triazinoindolethiones
Authors: Robba Max , Maume Daniel , Lancelot Jean‐Charles
Published: April 2009

Les triazinoindolethiones 2 et 3 obtenues par thionation des triazinoindolones 1 et 4 constituent des intermédiaires permettant d'accéder aux triazinoindoles 10 et 19 et qui se prêtent, par suite de leur équilibre tautomère avec des formes thiolactimes, à des réactions de N‐substitution et de S‐substitution. La méthylation conduit à des mélanges de dérivés N‐ et S‐méthylés qui out été séparés par chromatographie et identifiés par rmn 1H et par synthèse univoque.
Synthetic and structural studies of some chloro‐substituted methyl 2,1‐benzisoxazole‐3‐carboxylates and related compounds
Authors: Mccord Tommy J. , Smith David R. , Swan Janet K. , Goebel Anna M. , Thornton Donald E. , Yakshe Criss C. , Davis Alvie L.
Published: April 2009

Methyl 5‐chloro‐ and 5,7‐dichloro‐2,1‐benzisoxazole‐3‐carboxylates have been synthesized by treatment of o‐nitromandelic and 5‐chloro‐2‐nitroamandelic methyl esters, respectively, with thionyl chloride under appropriate reaction conditions. The structural assignments of both heterocyclic products were based on elemental and spectral analyses, and their conversion to the corresponding 5‐chloro‐ and 5,7‐dichloro substituted 2,1‐benzisoxazole‐3‐carboxylic acids and isatins. Methyl α‐chloro‐o‐nitrophenylacetate and o‐nitrophenylcarbomethoxymethinyl sulfite were also obtained from reactions of methyl o‐nitromandelate and thionyl chloride. A possible reaction mechanism involving two consecutive nucleophilic substitutions of methyl o‐nitromandelate with thionyl chloride was proposed to account for the formation of methyl 5‐chloro‐2,1‐benzisoxazole‐3‐carboxylate.
Mass spectrometry of nucleoside derivatives. Seleno analogs of purine and pyrimidine bases and nucleosides
Authors: Liehr J. G. , Weise C. L. , Wise Dean S. , Townsend Leroy B. , Crain P. F. , Milne George , Mccloskey James A.
Published: April 2009

Mass spectra of certain selenobases and selenonucleosides, and some of their trimethylsilyl and O,N‐permethyl derivatives have been studied from the standpoint of structural characterization, and in order to ascertain the influence of selenium on normal fragmentation patterns. Molecular ion abundances of the selenouracils are intermediate between those of the corresponding oxygen and sulfur analogs. Fragmentation processes are similar to those of the corresponding normal bases and nucleosides but with additional ions resulting from expulsion of Se or SeH in most cases. Trimethylsilylation occurs at approximately the same rate as for normal bases and nucleosides but the products show decreasing stability with prolonged heating. A least squares procedure is demonstrated which generates monoisotopic mass patterns and assists in interpretation of the mass spectra.
Condensation reactions of a comenaldehyde derivative
Authors: Looker James H. , Shaneyfelt Duane L. , Halfar Wayne
Published: April 2009

Condensation reactions of comenaldehyde methyl ether (I) with malonic acid, ethyl cyanoacetate, and cyanoacetamide to give β‐(5‐methoxy‐4H‐pyran‐4‐on‐2‐yl)acrylic acid (II), ethyl 2‐cyano‐3‐(5‐methoxy‐4H‐pyran‐4‐on‐2‐yl)propenoate (III), and 2‐cyano‐3‐(5‐methoxy‐4H‐pyran‐4‐on‐2‐yl)propenamide (IV), respectively, are described. Ultraviolet absorption spectra for 2‐hydroxymethyl‐5‐methoxy‐4H‐pyran‐4‐one, I and II are presented.
1,3‐Dioxolium‐, 1,3‐dithiolium‐ und 1,3‐diselenolium‐ionen ‐ aromatische strukturen oder durch heteroatome stabilisierte carbeniumionen?
Authors: Timm Uwe , Plücken Udo , Petersen Hermann , Meier Herbert
Published: April 2009

Protonation of the bases6, 7and8with trifluoroacetic acid was investigated on the basis of1–3C‐nmr measurements. Two models for the generated ions1–3are discussed. A decision is possible in favour of carbenium ions, which are stabilized by adjacent heteroatoms.
Stereospecific synthesis and antibiotic activity of some cephalosporin analogs
Authors: Bose Ajay K. , Ram Bhagat , Hoffman W. A. , Hutchison A. J. , Manhas M. S.
Published: April 2009

The strategy used for the stereospecific synthesis of benzofused octams as cepham analogs was the conversion of a 3,4‐dihydrothioisocarbostyril to a thioimidate, cycloaddition reaction to form a fused β‐lactam and subsequent removal of the alkylthio group by Raney nickel hydrogenolysis. Using azidoacetyl chloride for forming the β‐lactam and following known procedures, an amido side chain was generated. Two of the carba analogs of cephalosporin so produced showed low levels of antibacterial activity against a number of gram positive and gram negative organisms.
Introduction of a methoxyl group into indoles and 2,3‐dihydroindoles. A new synthesis of 5‐hydroxytryptamine (serotonin)
Authors: Saito Kunio , Kikugawa Yasuo
Published: April 2009

Methoxylation of the 5‐position of indoles and indolines was investigated. Treatment of 5‐bromo‐iodoles and indolines with cuprous iodide and sodium methoxide in methanol/dimethylformamide afforded the corresponding methoxy compounds. This methoxylation reaction was applied to the new synthesis of serotonin.
Synthesis of tetronic acid enamine. Dienamine derivatives from 3‐(2H)furanones
Authors: Chantegrel Bernard , Gelin Suzanne
Published: April 2009

The synthesis of 5‐aryl (or alkyl) aminomethylene‐3‐(1‐amino or 1‐alkylaminoethylidene)‐2,4‐dioxo‐(3H,5H)furans and 5‐arylaminomethylene‐3‐(1‐hydroxyethylidene)‐2,4‐dioxo‐(3H,5H)furans (new 3‐acetyltetronic acid derivatives) are described. The stereochemistry of these compounds from the 1H nmr data is discussed.
3‐Substituted imidazo[1,5‐a]pyridines
Authors: Albrecht W. L. , Corona J. A. , Edwards M. L.
Published: April 2009

Cyclization of amides of 2‐aminomethylpyridine gave imidazo[1,5‐a]pyridines. In several examples the literature preparation (phosphorus oxychloride) gave extensive tar formation. The use of phosphorus trichloride‐triethylamine (−20°) gave the desired imidazo[1,5‐a]pyridines.
Studies on quinoline derivatives and related compounds. VI. A novel displacement reaction of 1‐ethylquinolinium iodides with nucleophiles
Authors: Agui Hideo , Nakagome Takenari
Published: April 2009

The reaction of 4‐amino‐ (3a) and 4‐anilino‐3‐carbethoxy‐1‐ethyl‐6,7‐methylenedioxy‐quinolinium iodide (3b) with nucleophilic reagents produced 7‐substituted 4‐amino‐3‐carboxy‐1‐ethyl‐6‐hydroxyquinolinium betaines (5b‐d) and 7‐substituted 1‐ethyl‐1,4‐dihydro‐6‐hydroxy‐4‐phenylimino‐3‐quinolinecarboxylic acid (6b‐d), respectively, which led to 7‐substituted 1‐ethyl‐1,4‐dihydro‐6‐hydroxy‐4‐oxo‐3‐quinolinecarboxylic acids (1b‐d) by alkaline hydrolysis. With a variety of 1‐ethyl‐1,4‐dihydroquinoline carboxylates (16a‐e) these novel displacement reactions were attempted.