bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new ring opening reaction of N‐aminophthalimide hydrazones
Authors: Hearn Michael J. , Rosenberg Judith , Campbell Mary L. 
Published: April 2009

AbstractAraldehyde hydrazones III of N‐aminophthalimide underwent rapid ring opening reactions initiated by the addition of excess base to their refluxing methanolic solutions. The products were conveniently isolated through liquid‐liquid extraction as the stable sodium salts V, and acidification precipitated the resulting phthalic acid congeners VI from aqueous solution. Compounds III readily exchanged one hydrazine moiety for another. For example, IIId reacted with 2,4‐dinitrophenylhydrazine to give the 2,4‐dinitrophenylhydrazone of 4‐chlorobenzaldehyde (VIId, 93%). Nonetheless, IIIg reacted exclusively at the carboxaldehyde function to give products VIIIa and VIIIb.
Hydrogenolysis of the CO bond of the 1,2,4‐oxadiazine ring. Adams platinum hydrogenation of 3‐aryl‐5,6‐dihydro‐5‐(substituted)‐methylene‐4H‐1,2,4‐oxadiazine derivatives
Authors: Kawashima Etsuko , Takada Toyozo , Tabei Katsumi , Kato Tetsuzo 
Published: April 2009

AbstractAdams platinum hydrogenation of Z‐3‐aryl‐5,6‐dihydro‐5‐(substituted)methylene‐4H‐1,2,4‐ oxadiazine (1a‐f) proceeds very slowly through CO bond fission to give N‐(1‐substitutedcarbonyl‐2‐propylidene)benzamide ox‐ime derivative 2 as the main product. In the reaction of 5‐(arylcarbamoyl)methylene analogues 1d‐f, 5‐(aryl‐carbamoyl)methyl‐5,6‐dihydro‐3‐phenyl‐4H‐1,2,4‐oxadiazine (4) and N‐aryl‐3‐hydroxybutanamide derivative 5 are also obtained as well as compound 2.
Synthesis of 4,7‐dihydro‐4‐oxopyrrolo[2,3‐b]pyridine‐5‐carboxylic acid derivatives as potential antimicrobial agents
Authors: Vishwakarma Lal C. , Sowell J. Walter 
Published: April 2009

AbstractSynthetic approaches to 1‐benzyl‐7‐alkyl‐2,3‐dimethyl‐4,7‐dihydro‐4‐oxopyrrolo[2,3‐b]pyridine‐5‐carboxylic acids from 1‐benzyl‐2‐amino‐3‐t‐butoxycarbonyl‐4,5‐dimethylpyrrole are reported.
Antidiabetische wirkstoffe. V Lang‐ und verzweigtkettig substituierte chlor‐dihexylamino‐1,3,5‐triazine
Authors: Kreutzberger Alfred , Rose Ulrich 
Published: April 2009

AbstractDie nucleophile Substitution eines Chloratoms in 2,4‐Dichlor‐6‐dihexylamino‐1,3,5‐triazin (1) durch Amine (2a‐c) führt zu den Alkylamino‐chlor‐dihexylamino‐1,3,5‐triazinen 3a‐c. Für Strukturtyp 3 typische Signale in den 1H‐NMR‐Spektren sind das Triplett bei 0,9 ppm für die endständigen Methylgruppen und das Multiplett bei 3,3‐3,65 ppm für die den Stickstoffatomen benachbarten Methylengruppen. In Verbindungsklasse 3 finden sich Vertreter mit antidiabetischer, trichomonazider, antiviraler und anthelminthischer Wirksamkeit.
Synthesis of novel quinoxalines by ring transformation of 3‐quinoxalinyl‐l,5‐benzodiazepine
Authors: Kurasawa Yoshihisa , Shimabukuro Sayuri , Okamoto Yoshihisa , Takada Atsushi 
Published: April 2009

AbstractRing transformation of the 3‐quinoxalinyl‐l,5‐benzodiazepine (2) gave 3‐(benzimidazol‐2‐ylmethylene)‐2‐oxo‐l,2,3,4‐tetrahydroquinoxaline hydrochloride (4a), whose treatment with 5% sodium hydroxide provided the free base 5a, while refluxing of the 3′‐chloro‐l‐formyl derivative 3 in acetic acid and in 10% hydrochloric acid/acetic acid afforded 3‐(3‐oxo‐3,4‐dihydroquinoxalin‐2‐yl)‐1,2‐dihydro‐1‐formyl‐2‐oxo‐3H‐1,5‐benzodiazepine hydrochloride (7) and 3‐methyl‐2‐oxo‐l,2‐dihydroquinoxaline (6), respectively. Compounds 4a and 5a were converted into 3‐(α‐hydroxyiminobenzimidazol‐2‐ylmethyl)‐2‐oxo‐l,2‐dihydroquinoxaline (8) and 3‐(benzimidazol‐2‐ylcarbonyl)‐2‐oxo‐l,2‐dihydroquinoxaline (10), respectively, which were further transformed into 3‐(benzimidazol‐2‐yl)isoxazolo[4,5‐b]quinoxaline (9) and 12‐(benzimidazol‐2‐yl)‐6H‐quinoxalino[2,3‐bI1,5]benzodiazepine (11), respectively.
Regioselective synthesis of pyrido[2,3‐d]pyrimidines
Authors: Anderson Gary L. 
Published: April 2009

AbstractThe reaction of diethyl ethoxymethylenemalonate (1) and 6‐amino‐1,3‐dimethyluracil (2) was determined to be regioselective. Under acidic conditions the product was the previously isolated 7‐oxopyrido[2,3‐d]pyrimidine (3), while in the presence of one equivalent of base followed by thermal cyclization, the isomeric 5‐oxopyrido[2,3‐d]pyrimidine (5) is formed.
Reaction of ketenes with N, N‐disubstituted α‐aminomethyleneketones. XVI. Synthesis of N, N‐disubstituted 4‐amino‐5,6‐tetramethylene‐3‐phenyl‐2‐pyranones
Authors: Bargagna Alberto , Schenone Pietro , Longobardi Mario 
Published: April 2009

Abstract1,4‐Cycloaddition of phenylchloroketene (prepared in situ from α‐chlorophenylacetyl chloride and triethyl‐amine) to a number of N,N‐disubstituted (E)‐2‐aminomethylenecyclohexanones gave the corresponding adducts, namely N,N‐disubstituted 4‐amino‐3‐chloro‐3,4,5,6,7,8‐hexahydro‐2H‐1‐benzopyran‐2‐ones III in the case of aliphatic N,N‐disubstitution or aromatic N‐monosubstitution. Purification of III was possible only in the case of IIIh (NR2 = NMePh), therefore they were dehydrochlorinated in situ with DBN to give the title compounds in moderate overall yields.
Thermolysis of 7‐phenyl‐2,3,7‐triazabicyclo[3.3.0]oct‐2‐ene‐6,8‐dione
Authors: Majchrzak Michael W. , Kotelko Antoni 
Published: April 2009

AbstractThermolysis of the title compound in boiling xylene (138°) produces a 7.7/10.1/1.0 mixture of the N‐phenylimides of cis‐1,2‐cyclopropanedicarboxylic acid, citraconic acid, and itaconic acid. The imides of citraconic and itaconic acids are produced by hydrogen shifts. A completely concerted mechanism involving simultaneous hydrogen shift and cleavage of both C‐N bonds is unlikely in the present case because both hydrideshift products are formed and because the optimal arrangement for the hydrogen shift requires deformation of the imide ring and loss of imide resonance. The CN bond strengths in the title compound should be quite different. The products can arise either from two parallel pathways involving nitrogen‐containing dipoles or from a single nitrogen‐free trimethylene fragment.
Synthesis of 2‐thioxo‐3‐benzothiazolineacetonitrile and related products
Authors: D'Amico John J. , Suba Lydia , Ruminski Peter G. 
Published: April 2009

AbstractAttempts to thermally rearrange 2‐benzothiazolylthioacetonitrile (1) to the titled compound 8 failed. The reaction of 3‐chloromethyl‐2‐benzothiazolinethione with potassium cyanide in dimethylformamide (DMF) or dimethylsulfoxide (DMSO) at 25‐30° afforded 8 in 98% yield. Whereas replacing the DMF or DMSO solvent with acetone furnished the unexpected sulfide 9 in 92% yield. Substituting 3‐chloromethyl‐2‐benzoxazoline‐thione as the electrophile in the same reaction gave the sulfide 10 in 95% yield. Possible mechanisms and supporting nmr data are discussed.
Synthesis of 5H‐pyrido[2,3‐a]phenoxazin‐5‐one and 5H‐pyrido[3,2‐a]phenoxazin‐5‐one derivatives
Authors: Nan'ya Seiko , Maekawa Eturô , Hayakawa Hitoshi , Kitaguchi Yukio , Ueno Yoshio 
Published: April 2009

AbstractThe 5H‐pyrido[2,3‐a]phenoxazin‐5‐one derivatives and 5H‐pyrido[3,2‐a]phenoxazin‐5‐one derivatives were prepared by the condensation of substituted 2‐aminophenols with 6,7‐dibromo‐5,8‐quinolinequinone followed by dehalogenation in the presence of sodium hydrosulfite dissolved in aqueous pyridine under a nitrogen atmosphere.
Ring transformation of 3‐hydroxy‐1,2,5‐ and ‐1,2,4‐thiadiazoles and ‐isothiazoles into isothiazole, thiazole and thiophene derivatives
Authors: Mataka Shuntaro , Takahashi Kazufumi , Tashiro Masashi 
Published: April 2009

AbstractRing transformation of 3‐hydroxy‐1,2,5‐thiadiazole (1), 3‐hydroxy‐1,2,4‐thiadiazole (14), and 3‐hydroxyiso‐thiazole (18) by the reaction with acetic anhydride in the presence of DBU afforded isothiazoles 2‐5 and 13, thiazoles 15 and 16 and thiophenes 21‐25, respectively. The reaction of 1 with propionic anhydride gave isothiazole 13. The formation pathway of the products is mentioned.
Reaction of 2‐dimethylaminomethylene‐1,3‐diones with dinucleophiles. V. Synthesis of 5‐acyl‐1,2‐dihydro‐2‐oxo‐3‐pyridinecarbonitriles and 1,2,5,6,7,8‐hexahydro‐2,5‐dioxo‐3‐quinolinecarboxamides
Authors: Mosti Luisa , Schenone Pietro , Menozzi Ciulia 
Published: April 2009

AbstractThe reaction of open‐chain sym‐2‐dimethylaminomethylene‐1,3‐diones Ia‐d with sodium cyanoacetamide gave, generally in good yields, 6‐substituted 5‐acyl‐1,2‐dihydro‐2‐oxo‐3‐pyridinecarbonitriles IIa‐d, whereas cyclohexane sym‐2‐dimethylaminomethylene‐1,3‐diones Ie‐h afforded in general a mixture of 1,2,5,6,7,8‐hexahydro‐2,5‐dioxo‐3‐quinolinecarbonitriles and 5,6,7,8‐tetrahydro‐2,5‐dioxo‐2H‐1‐benzopyran‐3‐carboxamides, the latter being isolated in two cases. The reaction of Ie‐h with cyanoacetamide in refluxing anhydrous ethanol gave 1,2,5,6,7,8‐hexahydro‐2,5‐dioxo‐3‐quinolinecarboxamides IIIe‐h in excellent yields, whereas Ia‐d did not react with the exception of Ia which afforded in good yield 3‐pyridinecarboxamide IlIa. Other 3‐pyridine‐carboxamides were obtained by partial hydrolysis of nitriles IIb,d. 3‐Pyridine and 3‐quinoline carboxamides were hydrolyzed in satisfactory yields with hydrochloric acid to the corresponding carboxylic acids, which were decarboxylated in good yields to 5‐acyl‐2(1H)‐pyridinones and 7,8‐dihydro‐2,5(1H,6H)‐quinolinediones, respectively, by reflux in quinoline containing a catalytic amount of copper powder.
Synthesis of oxindole derivatives from N‐alkenyl‐o‐chloroanilides with zero‐valent nickel complex
Authors: Canoira L. , Rodriguez J. G. 
Published: April 2009

AbstractOxindole derivatives have been obtained from N‐alkenyl‐o‐chloroanilides by reaction with tetrakis(triphenylphosphine)nickel(0) in toluene as solvent in good yields. A detailed analysis of all the products of the reaction allows to confirm the postulated mechanism of the cyclization reaction. The o‐chloroanilides of the 3‐cyclohexenylacetic acid fails in the cyclization reaction, since the torsional hindrance seems to avoid that the endocyclic double bond may be orthogonally to the ortho‐σ‐nickel complex intermediate on the aromatic ring.
Lewis‐acid promoted aromatic cyclization of α‐chlorosulfides: Synthesis of ethyl isothiochroman‐1‐carboxylate and related compounds
Authors: Ishibashi Hiroyuki , Okada Motofumi , Iida Kyoko , Ikeda Masazumi 
Published: April 2009

AbstractA variety of ethyl isothiochroman‐1‐carboxylates and related compounds were synthesized by treatment of 2‐chloro‐2‐[(2‐arenyl)ethylthio]acetates with stannic chloride in methylene chloride. The same procedure was applied to the synthesis of ethyl 4‐chloro‐4‐methyltetrahydrothiopyran‐2‐carboxylate. Some isothiochroman‐1‐carboxylic acids were prepared and evaluated for antiinflammatory activity. Among the compounds tested, 7‐phenoxyisothiochroman‐1‐carboxylic acid showed weak activity.
Mass spectral fragmentation pattern of 2,3‐dimethyl‐ and 2‐methyl‐3‐phenyl‐4‐arylazoisoxazol‐5‐ones
Authors: Keats Neil G. , Singh Shyam K. , Summers Lindsay A. 
Published: April 2009

Abstract2,3‐Dimethyl‐4‐arylazoisoxazol‐5‐ones and 2‐methyl‐3‐phenyl‐4‐aryiazoisoxazol‐5‐ones undergo considerable fragmentation on electron impact. The base peaks in the mass spectra are at mass 56 and 118 respectively attributed to the N‐methylacetonitrile cation and the N‐methylbenzonitrile cation.
Brominated derivatives of 4‐hydroxy‐ and 4‐methoxy‐6‐methyl‐2H‐pyran‐2‐ones
Authors: De March P. , Moreno‐Mañas M. , Pi R. , Ripoll I. , Sánchez‐Ferrando F. 
Published: April 2009

AbstractTwenty‐five different brominated derivatives of 4‐hydroxy‐6‐methyl‐2‐pyrone (triacetic acid lactone) and 3‐acetyl‐4‐hydroxy‐6‐methyl‐2‐pyrone (dehydroacetic acid) have been prepared. Fifteen derivatives have not been previously described and the preparations of a few known products have been improved. Bromination at C‐3, C‐5, methyl group at C‐6 and deacetylations at C‐3 have been the types of reactions used.
Pyridazines. XXV. Formation of 2‐benzoyl‐2,5‐dihydro‐3‐pyridazinecarbonitrile derivatives in the reissert reaction of pyridazines
Authors: Dostal Wolfgang , Heinisch Gottfried 
Published: April 2009

AbstractPyridazines 1a, b on treatment with potassium cyanide/benzoyl chloride in a mixed solvent system gave 2‐benzoyl‐2,5‐dihydro‐3‐pyridazinecarbonitriles 3a, b together with products resulting from attack of one mole of cyanide ion and three moles of benzoyl chloride (5a, b). The structures of these novel compounds are proved. A plausible reaction mechanism is proposed, involving rearrangement of initially formed 2a, b into 3a, b. Furthermore, the synthesis of the pyridazine Reissert compound 2a is reported.
Preparation of pyrrolo[3,2,1‐jk]carbazole by nickel(0) mediated ring contraction of pyrrolo[3,2,1‐kl]phenothiazine. Proton NMR and mass spectral studies
Authors: Klingstedt Tomas , Hallberg Anders , Dunbar Philip , Martin Arnold 
Published: April 2009

AbstractPyrrolo[3,2,1‐jk]carbazole 1a, the previously unreported 16π‐electron parent compound, has been synthesized by treatment of pyrrolo[3,2,1‐kl]phenothiazine 2a with a 1:1 mixture of bis(1,5‐cyclooctadiene) nickel(0) and 2,2′‐bipyridyl. An unequivocal assignment of the 1H nmr spectrum of 1a was made by decoupling experiments and by comparison with the 1H nmr spectrum of 1,9‐dideuteriopyrrolo[3,2,1‐jk]carbazole 1b. Metastable ion studies, exact mass measurements and the dideuterioderivative 1b were utilized to investigate the electron impact induced fragmentation of 1a.
Obtention d'hétérocycles par action de binucléophiles diazotés sur des chalcones: Influence du substituant en position 2
Authors: Simon Dominique , Lafont Olivier , Farnoux Claude Combet , Miocque Marcel 
Published: April 2009

AbstractLa réactivité de chalcones substituées en position 2 vis‐à‐vis de binucléophiles α.azotés (hydrazines, thiourée, guanidine) est mise à profit pour synthétiser des hétérocycles variés (pyrazoles, pyrazolines, pyrimidines), ainsi que des hydrazines substituées. Une interprétation générale est donnée, en fonction de la nature du substituant R du système énone, de la nature du binucléophile, et du milieu réactionnel.
Preparation of 1,8‐naphthalimides as candidate fluorescent probes of hypoxic cells
Authors: Middleton Richard W. , Parrick John 
Published: April 2009

AbstractA number of nitro‐ and dinitro‐1,8‐naphthalimides have been prepared as potential fluorescent probes of hypoxic cells. The susceptibility of 4‐nitro‐1,8‐naphthalic anhydrides and ‐naphthalimides to nucleophilic displacement of the nitro group has been demonstrated by reaction with 1‐butanethiol to yield 4‐butylthio derivatives. Attempted nitration of these 4‐butylthio derivatives with sodium nitrate and concentrated sulphuric acid yielded the corresponding sulphoxides in high yield.
Reaction of benzoxazolone with 2,4‐dinitrochlorobenzene: Formation of 10‐(2,4‐dinitro)phenyl‐3‐nitrophenoxazine
Authors: Moreno‐Mañas M. , Sánchez‐Ferrando F. , Valle S. 
Published: April 2009

AbstractArylation of benzoxazolone 1 by 2,4‐dinitrochlorobenzene 2 under solid‐liquid phase transfer catalysis (PTC) gave 3‐(2,4‐dinitro)phenylbenzoxazolone 3 and 10‐(2,4‐dinitro)phenyl‐3‐nitrophenoxazine 4. Neither PTC nor copper catalysis achieved arylation of 1 by less activated aryl halides.
Hypervalent iodine oxidation. Synthesis of spin labeled, 1‐oxyl‐2,2,6,6‐tetramethylpiperidine derivatives
Authors: Moriarty Robert M. , Prakash Indra , Penmasta Raju 
Published: April 2009

AbstractOxidation of 1‐oxyl‐2,2,6,6‐tetramethyl‐4‐piperidone (1) with [I,I‐bis(acetoxy)iodo]benzene in methanolic potassium hydroxide yields 1‐oxyl‐4,4‐dimethoxy‐3‐hydroxy‐2,2,6,6‐tetramethylpiperidine (2). Treatment of 2,2,6,6‐tetramethyl‐4‐piperidone (3) with [I,I‐bis(acetoxy)iodo]benzene in methanolic potassium hydroxide gave 3‐methoxy‐2,2,6,6‐tetramethyl‐4‐piperidone (4) which on oxidation with 30% hydrogen peroxide and catalytic amount of sodium tungstate gave 1‐oxyl‐3‐methoxy‐2,2,6,6‐tetramethyl‐4‐piperidone (5). The esr spectra of 1‐oxyl‐4,4‐dimethoxy‐3‐hydroxy‐2,2,6,6‐tetramethylpiperidine (2) as well as 1‐oxyl‐3‐methoxy‐2,2,6,6‐tetramethyl‐4‐piperidone (5) show three lines.
1‐Azabenz[a]anthracene and 9‐azabenz[a]anthracene
Authors: Tanga Mary J. , Almquist Ronald G. , Smith Thomas H. , Wu Helen Y. , Reist Elmer J. 
Published: April 2009

AbstractThe synthesis of 1‐azabenz[a]anthracene and 9‐azabenz[a]anthracene are presented.
Arylidène‐5 méthyl‐6 4H pyridazines substitutées en 3 et systèmes a noyaux condenées
Authors: Taoufik J. , Couquelet J. M. , Couquelet J. D. , Tronche P. 
Published: April 2009

AbstractEn vue de prospecter les activités pharmacologiques des arylidène‐5 méthyl‐6 4H pyridazines, plusieurs series de derives substitues en position 3 ont été préparées au départ de pyridazinones 1 synthétisées au laboratoire. Les chloropyridazines 3 constituent des intermédiaires permettant d'accéder soit aux amino‐pyridazines 4, soit aux hydrazino‐pyridazines 5. Ces dernières peuvent à leur tour donner lieu à la formation de systèmes condensés tels que les triazolopyridazines 6 et les tétrazolopyridazines 7 ou encore de dérivés pyrazoliques 8 éventuellement fonctionnalisés. Les spectres de rmn 1H confirment la structure des différents composés obtenus.
(Perhalogenmethylthio)heterocyclen. XIX. Darstellung und eigenschaften von tetrakis(trifluoromethylthio)thiophen, tetrakis‐(trifluoromethylthio), ‐1,2‐dithiin, 2,3,4‐tris(trifluoromethylthio)‐5‐trifluor‐methylthiophen und 1‐chlor‐tetrakis(trifluormethylthio)pyrrol
Authors: Haas Alois , Klare Christiane , Krächter Hans‐udo 
Published: April 2009

AbstractBis(trifluormethyl(thio)acetylen reagiert mit Schwefel bei 170° zu Tetrakis(trifluormethylthio)thiophen, ‐1,2‐dithiin und 2,3,4‐Tris(trifluormethylthio)‐5‐trifluormethylthiophen. Mit Natriumhypochlorit setzt sich Tetrakis(trifluormethylthio)pyrrol in schwach alkalischer Lösung zu N‐Chlor‐tetrakis(trifluormethylthio)pyr‐rol um. Physikalische Daten der neuhergestellten Verbindungen werden angegeben.
3,6‐diisopropyl‐2‐hydroxypyrazine and 3,6‐diisopropyl‐2‐pyrazinethiol as carriers of some alkoxycarbonyl groups
Authors: Ohta Akihiro , Inagawa Yukiko , Mitsugi Chie 
Published: April 2009

AbstractSome derivatives of benzyloxycarbonylated 3,6‐diisopropyl‐2‐hydroxypyrazine and 3,6‐diisopropyl‐2‐pyrazinethiol were prepared and shown to be the versatile benzyloxycarbonylation reagents for amines and amino acids. It was also ascertained that 3,6‐diisopropyl‐2‐hydroxypyrazine and 3,6‐diisopropyl‐2‐pyrazine‐thiol serve effectively as carriers of the β,β,β,‐trichloroethoxycarbonyl group.
On the synthesis of geometric isomers of 2‐methyl (or phenyl)‐4‐[α‐arylethylidene]‐5(4H)‐oxazolones
Authors: Cativiela C. , De Villegas M. D. Diaz , Meléndez E. 
Published: April 2009

AbstractSeveral Z‐2‐methyl(or phenyl)‐4‐[α‐arylethylidene]‐5(4H)‐oxazolones 3Z, 4Z were prepared. The results obtained were compared by diazomethane insertion and condensation procedure. In order to synthesize E‐2‐phenyl‐4‐[α‐arylethylidene]‐5(4H)‐oxazolones 4E hydrogen bromide isomerization in dry benzene was used.
Synthesis of some 4‐acetyl‐3,5‐dioxo‐2,3,4,5‐tetrahydro[1]benzoxepine or benzothiepine and 6‐acetyl‐5,7‐dioxo‐6,7,8,9‐tetrahydro‐5H‐benzocycloheptene derivatives
Authors: Deshayes Christian , Chabannet Michel , Gelin Suzanne 
Published: April 2009

AbstractThe title compounds were prepared from benzoxepino‐, benzothiepino‐ or benzocycloheptaisoxazolones which in turn were synthetized from simple materials.
On the mechanism of steroidal osazone formation. Synthesis of triazole
Authors: Catsoulacos Panayotis 
Published: April 2009

AbstractUsing a substrate steroidal α‐bromo, α‐hydroxy and α‐acetoxyketones, we studied the mechanism of osazone formation. A synthetic approach for the preparation of cholestano‐2′‐phenyl[2,3‐d]triazole is described.
Action of hydrogen peroxide on some 2‐aminooxazoles and imidazolin‐2‐ones. Isolation of hydroperoxyimidazolidin‐2‐ones
Authors: Ginanneschi M. , Chelli M. , Rapi G. 
Published: April 2009

AbstractThe reaction of some 2‐aminooxazoles and imidazolidin‐2‐ones with hydrogen peroxide afforded stable trans‐β‐hydroxyhydroperoxy‐ or dihydroperoxyimidazolidin‐2‐ones according to the reaction conditions. In the case of 3a‐hydroxy‐7a‐hydroperoxyoctahydro‐2H‐benzimidazolidin‐2‐one, the trans isomer is forbidden and cis adduct was isolated. A radical pathway to these hydroperoxides is proposed. From 2‐amino‐4‐methyloxazole and hydrogen peroxide 2‐amino‐2‐hydroxy‐4‐methyloxazolidin‐4‐yl peroxyacetate was also isolated.
1,1‐Disubstituted‐2,3,4,9‐tetrahydro‐1H‐pyrido[3,4‐b]indolecarboxylic acid esters and ketones. The base catalyzed transformation of 1‐(2′,3′,4′,9′‐tetrahydrospiro[cyclohexane‐1,1′‐[1H]pyrido[3,4‐b]indol]‐2‐yl)alkanones into 2‐(4,9‐dihydro‐3H‐pyrido[3,4‐b]indol‐1‐yl)‐1 ‐alkylcyclohexanols
Authors: Bobowski George , Shavel John 
Published: April 2009

AbstractCondensation of 1H‐indole‐3‐ethanamines 1 with cyclic β‐keto esters 2 under azeotropic conditions followed by acid‐catalyzed ring closure of the resulting enamines 3 gave 2′,3′,4′,9′‐tetrahydrospiro[piperidine‐3,1′,‐[1H]pyrido[3,4‐b]indole] ‐4‐carboxylic acid alkyl esters 4. Condensation of 1 with 2‐acylcycloalkanones 8 gave two types of enamines, 10 and 11, respectively. Enamines 10 on treatment with acid gave 1‐(2′,3′,4′,9′‐tetrahydro‐3H‐pyrido[3,4‐b]indol‐1‐yl)‐1‐alkylcyclohexanols 17. Compounds 17 were further dehydrated to give cycloalkane derivatives 19.
A new method for the synthesis of novel 1‐aryl‐3‐quinoxalinyl‐1,2,4‐triazol‐5‐ones
Authors: Kurasawa Yoshihisa , Muramatsu Muneto , Hotehama Keizo , Okamoto Yoshihisa , Takada Atsushi 
Published: April 2009

AbstractThe reactions of 3‐methoxycarbonylmethylene‐2‐oxo‐1,2,3,4‐tetrahydroquinoxaline 1 with aryl diazonium salts gave 3‐(α‐aryldiazenylmethoxycarbonylmethylene)‐2‐oxo‐1,2,3,4‐tetrahydroquinoxalines 2a‐c, whose reactions with hydrazine hydrate afforded 3‐(α‐aryldiazenylhydrazinocarbonylmethylene)‐2‐oxo‐1,2,3,4‐tetrahydroquinoxalines 3a‐c. The reactions of 3a‐c with nitrous acid resulted in the Curtius rearrangement to provide the 1‐aryl‐3‐quinoxalinyl‐1,2,4‐triazol‐5‐ones 4a‐c.
Long chain heterocyclic dyes. Part Two. Surface active dyes
Authors: Barni Ermanno , Savarino Piero , Viscardi Guido , Pelizzetti Ezio 
Published: April 2009

AbstractA series of heterocyclic cyanine dyes were prepared. Unsymmetrical dyes showed self‐micellizing properties due to the presence of two positive charges and of a long alkyl chain. Symmetrical dyes, containing three positive charges and not containing the hydrophobic chain, did not give rise to micelles. The physical properties of the dyes and their spectra were briefly discussed. Cationic (HTAB) and anionic (SDS) surfactants gave strong interactions with surface active dyes, leading to deaggregation and solvation phenomena.
Migratory aptitudes in pinacol rearrangement of vic‐dihydroxychlorins
Authors: Chang C. K. , Sotiriou Chariklia 
Published: April 2009

AbstractWhen vic‐dihydroxychlorins undergo a pinacol‐pinacolone rearrangement, the migratory aptitudes of common porphyrin substituents follow the order: alkyl groups, propionate side chain, H > methyl group > acetate side chain. C‐Alkylchlorins can be made by extremely short syntheses utilizing such rearrangement.
Synthesis of indazole derivatives from a N,N‐disubstituted 2‐halobenzoic hydrazide. Crystal structure of 1,2‐pentamethylene‐5‐nitro‐1,2‐dihydro‐3H‐indazol‐3‐one
Authors: Arán V. J. , Stud M. , Foces‐Foces C. , Cano F. H. , Martínez‐Ripoll M. 
Published: April 2009

AbstractThermal cyclization of the N,N‐disubstituted 2‐chlorobenzoic hydrazide 1 yields the 1,2‐pentamethylene indazolone 5, which structure is confirmed by X‐ray crystallography. We suggest that the reaction proceeds through an N,N‐alkyl shift in an initially formed indazolinium salt 2. An intermediate 1‐(5‐chloropentyl)indazolol 4 has been isolated.
Synthesis of 5‐(β‐D‐ribofuranosyl)‐1,2,4‐oxadiazole‐3‐carboxamide
Authors: Hennen William J. , Robins Roland K. 
Published: April 2009

AbstractThe title compound was synthesized in three steps from ethoxycarbonylformamide oxime (5) and 3,4,6‐tri‐O‐acetyl‐2,5‐anhydroallonyl chloride (4b) in 62% overall yield. An acid catalyzed de‐esterification was required to prevent a facile base catalyzed elimination reaction.