bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new look into the rothemund meso‐tetraalkyl and tetraarylporphyrin synthesis
Authors: Gonsalves A. M. D'A. Rocha , Pereira Mariette M. 
Published: April 2009

Abstractmeso‐Tetraalkylporphyrinogens are easily formed and unexpectedely stable compounds. Only through forced oxidation can they efficiently be converted into porphyrins. meso‐Tetraphenylphlorin was trapped as an intermediate in the Rothemund meso‐tetraphenylporphyrin synthesis.
A new method for the synthesis of novel 1,2,4‐triazolo[3,4‐f][1,2,4]triazines
Authors: Kurasawa Yoshihisa , Okamoto Yoshihisa , Takada Atsushi 
Published: April 2009

AbstractNovel compounds 8‐(quinoxalin‐2‐yl)‐1,2,4‐triazolo[3,4‐f][1,2,4]triazines 3a,b were obtained by a new annulation method in the 1,2,4‐triazine synthesis.
Carbon‐13 NMR study of 1‐methyl‐3‐phenyl‐4‐diazo‐5‐benzoylamidopyrazole and other model pyrazole compounds
Authors: Cecchi Lucia , Melani Fabrizio , De Sio Francesco 
Published: April 2009

AbstractA 13C nmr study of a diazo, of two diazonium salts and of some other model pyrazole compounds is reported. It is found that the C‐4 diazo carbon is more shielded than the normal sp2 pyrazole hybridized carbon, while its diazonium salt is more deshielded. The electron density on the C‐4 of the diazopyrazole is probably due to the positive charge on the terminal nitrogen. Thus the 13C chemical shift values allowed us to understand the chemical behaviour of a compound of potential antitumor activity.
2‐Azabicyclo[2.2.1]heptane‐3‐carboxylic acid ‐ A bicyclic proline
Authors: Gaitanopoulos Dimitri E. , Weinstock Joseph 
Published: April 2009

AbstractDiels‐Alder reaction of cyclopentadiene and methyl N‐carbobenzyloxy‐2‐iminoacetate generated in situ from methyl 2‐chloro‐N‐carbobenzyloxyglycinate by triethylamine gave the N‐carbobenzyloxy unsaturated bicyclic proline ester. This was converted in two steps to 2‐azabicylo[2.2.1]heptane‐3‐carboxylic acid. In contrast to N‐carbobenzyloxy‐L‐proline methyl ester, the corresponding bicyclic proline ester was resistant to hydrolysis catalyzed by carboxypeptidase Y.
Photochemistry of host‐guest complexes. VIII. The photoreaction of pyrazinedicarbonitrile derivatives having a crown ether moiety in the presence of an ω‐diethylamino‐1‐alkanaminium salt
Authors: Tada Masaru , Hamazaki Hirohide , Tsuzuki Koichi 
Published: April 2009

AbstractIrradiation of 5‐[(benzo‐18‐crown‐6)‐4′‐yl]pyrazine‐2,3‐dicarbonitrile and 5‐(3,4‐dimethoxyphenyl)pyrazine‐2,3‐dicarbonitrile in the presence of ω‐diethylamino‐l‐alkanaminium ion caused the reductive decyanation to give pyrazinemonocarbonitrile derivatives. The reaction is initiated by a single electron transfer from the tertiary amino group of the diamine. The complex formation between the crown ether moiety and the ω‐ diethylamino‐l‐alkanaminium ion enhances the photoreaction.
Studies related to cephalosporins. Part 2 . Displacement reactions on 3‐bromomethylcephems with salts of carboxylic acids
Authors: Botta Maurizio , De Angelis Francesco , Grgurina Ingeborg , Marzi Mauro , Nicoletti Rosario 
Published: April 2009

AbstractThe reactivity of Δ3‐ and Δ2‐3‐bromomethylcephems toward carboxylate nucleophiles has been studied. The Δ3‐bromomethylcephem 1, less reactive than the Δ2‐analogue 4, is converted in high yields into 3‐acyl‐oxymethyl‐3‐cephems 2a‐d, generally with no isomerization of the double bond, only within a narrow range of conditions. In particular, the Δ3‐7‐aminocephalosporanic acid (7‐ACA) derivative 2a has been obtained as the only product in 91% yield by treatment of 1 with triethylammonium acetate in acetic acid.The Δ2‐bromomethyl‐cephem 4 is easily converted into the Δ2‐acyloxymethyl‐cepheras 5a‐d without double bond isomerization, in very high yields.
The synthesis and chemistry of some bis‐aziridinylketones and their spectral study
Authors: Lin Tay‐Yean , Kingsbury Charles A. , Adelfang Jules , Cromwell Norman H. 
Published: April 2009

AbstractThe synthesis and spectral characteristics of certain bis(1‐alkyl‐3‐phenyl‐2‐aziridinyl)ketones are reported. The reactions of 1,2,4,5‐tetrabromo‐1,5‐diphenyl‐3‐pentanone (2) with primary amines are assumed to have a mechanism similar to that of a simple dibromo‐ketone. The so‐called cis, cis‐ or trans, trans‐configurations of the bis‐aziridinylketones were determined by 1H and 13C nmr spectra.
Some new aspects on the chemistry of 1,4‐benzoxazines
Authors: Chioccara Francesco , Novellino Ettore 
Published: April 2009

Abstract3‐Methyl (3a) and 3‐t‐butyl‐1,4‐2H‐benzoxazine (3b) were synthesized by cyclization of the appropriate acetamidoketone (Scheme 1). The former is a highly unstable molecule which rapidly converts in an intractable mixture, while the latter slowly undergoes aerial oxidation affording the hemiacetal 4. The 4H‐forms of the same 3‐methyl (6a) and of the parent 1,4‐benzoxazine (9) could be obtained as 4‐acetyl derivatives. This latter, by hydrolysis, gave the cyclic trimer 10.
Preparation of cyclohepta and benzo[ef]cycl[3.2.2]azines
Authors: Noguchi Michihiko , Tanigawa Noriyuki , Kajigaeshi Shoji 
Published: April 2009

AbstractSome cyclohepta[ef]cycl[3.2.2]azines were prepared from cyclohepta[hi]indolizines and electron deficient acetylenes in the presence of appropriate oxidants. Also, benzo[ef]cycl[3.2.2]azines were obtained similarly in good yields.
4,5‐Dibenzyloxybenzyne as a synthon for diels‐alder reactions. The synthesis of 6,7‐dihydroxy‐1,4‐ethano‐1,2,3,4‐tetrahydroisoquinolines as rigid analogs of adrenergic agents. Assignment of proton and carbon‐13 NMR parameters using homonuclear and heteronuclear two‐dimensional chemical shift correlation NMR spectroscopy
Authors: Muellner Frank W. , Abdel‐Sayed Ashraf N. , Bauer Ludwig 
Published: April 2009

AbstractThe synthesis of several rigid analogs of catecholamine type of adrenergic agents is reported. Their synthesis began with a Diels‐Alder cycloaddition of 4,5‐dibenzyloxybenzyne (generated from 4,5‐dibenzyloxyan‐thranilic acid) to 1‐(2‐trans‐phenylvinyl)‐2‐pyridone and 1‐benzyl‐3‐benzyloxy‐2‐pyridone. The unsaturated amides so produced were reduced first with hydrogen and palladium and then with lithium aluminum hydride to provide 6,7‐dihydroxy‐1,4‐ethano‐1,2,3,4‐tetrahydroisoquinolines. Homonuclear and heteronuclear two‐dimensional chemical shift correlation nmr spectroscopy confirmed the structure of the bridged tetra‐hydroisoquinolines and led to the unambiguous assignment of the 1H and 13C nmr chemical shifts of key compounds.
Synthesis of pyrrolo[2,1‐c][1,4]benzoxazepines. 1. A novel heterocyclic ring system
Authors: Effland Richard C. , Davis Larry 
Published: April 2009

AbstractThe synthesis of a novel pyrrolo[2,1‐c][1,4]benzoxazepine ring system (II) by a nucleophilic aromatic fluoride displacement‐cyclization is described. Aminoalkyl derivatives were prepared by either the Mannich reaction, or Vilsmeier formylation to provide the 3‐formyl derivative which was further elaborated.
α‐Halo sulfides in the alkylation of 2‐pyrimidinones
Authors: Strande Per , Benneche Tore , Undheim Kjell 
Published: April 2009

AbstractWhen α‐halo sulfides are reacted with ambident 2‐pyrimidinones, the major product is due to N‐alkylation, the minor product to O‐alkylation. N‐Alkylation is favoured by the presence of a tertiary amine in a solvent of low dielectric constant and also by a change of the α‐halo sulfide substituent from chlorine to iodine. Complete selectivity can be achieved. The course of the reaction is rationalized in terms of the HSAB‐principle.
Non‐steroidal antiinflammatory agents. 3. Synthesis of 3‐hydroxy‐3‐hydroxyphenyl‐2,4‐dioxo‐1,2,3,4‐tetrahydroquinolines
Authors: Faber Kurt , Steininger Heinz , Kappe Thomas 
Published: April 2009

AbstractThe acid‐catalyzed condensation of quinisatines 5a‐c or their aminals 4a‐c with phenols 6a‐i led to a number of 3‐hydroxy‐3‐hydroxyphenyl‐2,4‐dioxo‐1,2,3,4‐tetrahydroquinolines 7a‐s which were considered as potential antiinflammatory agents.
Synthesis of 4‐thiocarbamoyl‐5‐aminopyrazoles
Authors: Giori P. , Veronese A. C. , Vicentini C. B. , Guarneri M. 
Published: April 2009

AbstractAryl and t‐butylhydrazines react with 2‐cyano‐3‐ethoxythiocrotonamide affording 2‐cyano‐3‐aryl‐t‐butylhy‐drazinothiocrotonamides. These intermediates can be easily cyclized to 4‐thiocarbamoyl‐5‐aminopyrazoles by heating a few minutes in a strong base. Alkylhydrazines react with 2‐cyano‐3‐ethoxythiocrotonamide yielding directly a mixture of the cyclized compounds 4‐cyano‐5‐aminopyrazoles and 4‐thiocarbamoyl‐5‐aminopyr‐azoles.
Configurations and conformations of some 3‐acetoxy‐cis‐hexahydro‐2(3H)‐benzofuranones
Authors: Dolmazon René , Gelin Suzanne 
Published: April 2009

AbstractCatalytic hydrogenation of some 2‐ethoxalylcyclohexanones afforded a mixture of isomeric 3‐hydroxy‐cis‐hexahydro‐2(3H)‐benzofuranones. Three 5‐t‐butyl substituted diastereomers and two 5‐unsubstituted epimers were separated and identified as acetates. The configurations were determined by 350 MHz 1H‐nmr analysis. The conformations of these fused‐compounds are discussed.
A new heterocyclic system: Imidazo[2,1‐d][1,5]benzothiazepine. Its synthesis from 4‐amino‐2,3‐dihydro‐1,5‐benzothiazepine
Authors: Walia Jasjit S. , Walia Amrik S. , Lankin David C. , Petterson Robert C. , Singh Janak 
Published: April 2009

AbstractThe synthesis of 4‐amino‐2,3‐dihydro‐1,5‐benzothiazepine and its transformation to the new heterocycle Imidazo[2,1‐d][1,5]benzothiazepine is described.
Synthesis of novel 3‐substituted 1,5‐benzodiazepine derivatives
Authors: Kurasawa Yoshihisa , Shimabukuro Sayuri , Okamoto Yoshihisa , Ogura Kuniyoshi , Takada Atsushi 
Published: April 2009

AbstractThis paper describes an improved method for the synthesis of 3‐(3‐chloroquinoxalin‐2‐yl)‐1,2‐dihydro‐1‐formyl‐2‐oxo‐3H‐1,5‐benzodiazepine (2) and its conversions into novel 3‐substituted 1,5‐benzodiazepine derivatives (3a,b and 4a,b).
Synthesis of 4,9‐dimethoxy‐1H‐benz[f]indole
Authors: Malesani Giorgio , Ferlin Maria Grazia 
Published: April 2009

AbstractA three‐step synthesis of 4,9‐dimethoxy‐1H‐benz[f]indole (4) starting from 1,4‐dimethoxy‐2‐aminonaphthalene (1) is described. Compound 1 was condensed with epichlorohydrin in acidic methanolic solution and the crude reaction product, purified by column chromatography, was cyclized to compound 3 by reflux heating in bromobenzene solution in the presence of excess diethylaniline. Appropriate oxidization with periodate in alkaline solution produced the title compound 4.
Studies on pyrazines. 12. N‐oxidation of aminopyrazines with m‐chloroperbenzoic acid
Authors: Sato Nobuhiro 
Published: April 2009

AbstractN‐Oxidation reactions of 2‐aminopyrazines, substituted by methyl or phenyl groups at C‐3 or C‐5, with m‐chloroperbenzoic acid were undertaken to obtain the 2‐aminopyrazine 1‐oxides.
Synthesis of some 2,4‐disubstituted tetrahydropyrimido[4,5‐b]quinolines as potential antitumor agents
Authors: Gangjee Aleem , Ohemeng Kwasi A. , Tulachka Jacqueline J. , Lin Fu‐Tyan , Katoh Arthur A. 
Published: April 2009

AbstractCyclocondensations of two 2,4‐disubstituted 6‐aminopyrimidines with 2‐chloro‐1‐cyclohexenecarboxaldehyde afforded in each case a new regiospecific synthesis of tricyclic, linear disubstituted 6,7,8,9‐tetrahydro‐pyrimido[4,5‐b]quinolines 2 and 3 in excellent yields. The linear structures and hence the regiospecificity of the synthesis were established using 1H nmr and 13C nmr. The growth of leukemia L1210 cells in culture was inhibited 50% by 2 at 30 × 10−6M and 48% by 3 at 100 × 10−6M.
Synthesis of a substituted tetrahydropyrimido[4,5‐c][2,7]naphthyridine as a tricyclic 5‐deaza nonclassical folate
Authors: Gangjee Aleem , Ohemeng Kwasi A. 
Published: April 2009

AbstractCondensation of 2,6‐diamino‐4‐hydroxypyrimidine with 1‐benzoyl‐1,2,3,6‐tetrahydropyrimidine‐5‐carboxal‐dehyde (4) afforded a mixture of angular and linear tricyclic tetrahydropyrimidonaphthyridines. Separation of the mixture was affected by fractional precipitation. Condensation of 2,4,6‐triaminopyrimidine with 1‐benzoyl‐4‐chloro‐1,2,3,6‐tetrahydropyridine (5) was regiospecific and afforded only the substituted angular tetra‐hydropyrimido[4,5‐c][2,7]naphthyridine (2). The vinyl aldehyde 4 and the chlorovinyl aldehyde 5 were prepared by modifications of literature procedures.
Mass spectrometry of 2,4‐substituted carcinogenic thiazoles and their metabolites
Authors: Mattammal Michael B. , Zenser Terry V. , Davis Bernard 
Published: April 2009

AbstractThe fragmentation pattern of some selected 2,4‐substituted carcinogenic thiazoles and their metabolites are described. Multiple modes of cleavages are seen when the 2‐amino group in thiazole is substituted.
The non‐intermediacy of benzo[1,2‐d:2,3‐d']bistriazole during the diazotization of a 4‐aminobenzotriazole
Authors: Oliver James E. 
Published: April 2009

AbstractLabeling studies with 15N demonstrate that a diazonium ion prepared from a 4‐aminobenzotriazole does not cyclize to a tricyclic intermediate.
Novel synthesis of pyrazole and pyrazoline derivatives
Authors: Matsumura Noboru , Kunugihara Akira , Yoneda Shigeo 
Published: April 2009

AbstractThe 1,4‐dianion of acetophenone N‐ethoxycarbonylhydrazone reacts with carbonyl compounds such as esters, acyl chlorides, amides and α‐haloketones such as phenacyl chloride, 1‐chloroacetone, 1,3‐dichloroacetone, to produce pyrazole and pyrazoline derivatives in good yields, respectively.
Reaction of 1,3,4‐thiadiazolo and 1,3,4‐triazolo[3,2‐c]quinazoline derivatives with active methylene compounds
Authors: Molina P. , Arques A. , Cartagena I. , Valcarcel M. V. 
Published: April 2009

AbstractFused quinazoline derivatives 1 and 4 react with active methylene compounds and depending on the annelated five‐membered ring, two types of transformations have been observed. The 1,3,4‐thiadiazolo[3,2‐c]quinazoline 1, underwent the five‐membered ring opening reaction to afford the 3,4‐dihydroquinazolines 2 in good yields, whereas the 1,3,4‐triazolo[3,2‐c]quinazoline 4 underwent nucleophilic attack at 2‐position of the quinazoline ring to yield the corresponding 1,2,4‐triazoles 5.
3‐(4‐Hydroxyphenylthio)pyrrolidine‐2,5‐diones
Authors: Pastor Stephen D. , Hessell Edward T. , Odorisio Paul A. , Spivack John D. 
Published: April 2009

Abstract3‐(4‐Hydroxyphenylthio)pyrrolidine‐2,5‐diones were prepared by the conjugate addition of substituted 4‐hydroxybenzenethiols to 1‐alkyl‐1H‐pyrrole‐2,5‐diones. The analytical and spectral data are reported.
Some heterocyclic sulfonyl derivatives
Authors: Cremlyn Richard J. , Swinbourne Frederick J. , Shode Olufemi 
Published: April 2009

Abstract2,3‐Diphenylpyrazine, 3,4‐diphenylfurazan and 2‐methyl‐4,5‐diphenyl oxazole react with chlorosulfonic acid to give the sulfonyl chlorides Ia, IIa, IIIa. The chlorides were condensed with nucleophiles to give thirteen derivatives. 4′,4″‐bis‐Dimethylsulfamoyl‐2‐methyl‐4,5‐diphenyloxazole (Illb) was oxidized with bromine to give 4,4′‐bis‐dimethylsulfamoylbenzil (IV), which by heating with ethylenediamine afforded the 4′,4″‐bis‐dimethylsulfamoylpyrazine (V). The spectral data of the various compounds are briefly discussed.
Synthesis and spectral properties of 7‐(N‐arylsulfonyl)aminocoumarins, a new class of fluorescent pH indicators
Authors: Wolfbeis Otto S. , Baustert John H. 
Published: April 2009

Abstract7‐Arylsulfonylamino‐coumarins 3 and 5, with electron‐delocalizing substituents in position 3 were obtained by condensation of 4‐arylsulfonylamino‐2‐hydroxybenzaldehyde with various (hetero)arylacetic esters and by other methods. Oxidative cyanation using potassium cyanide and elemental bromine gave the corresponding 4‐cyano derivatives 6a,b.The absorption and emission maxima of coumarins 3 and 5 in organic solvents and in water of different pH were determined. All showed bright blue fluorescence in organic or acidic aqueous solution, which is shifted to the green in alkaline solution. The 4‐cyano derivatives 6a, b exhibit green fluorescences, which change to yellow in alkaline solution. Simultaneously the color changes from yellow to orange.The pKa values of compounds 3 and 5 were found to lie between 6.33 and 7.06, whereas for the 4‐cyano derivatives they were distinctly lower (5.66‐5.95). The spectral changes observed in the near neutral pH range may render the new compounds useful indicators for the measurement of physiological pH's.
Heteroyohimbane a noyau furannique. Nouvelle voie d'acces aux derives de la furo[3,2‐c]pyrone et de la furo[3,2‐c]pyridine
Authors: Mavoungou‐Gomès Louis , Bruneton Jean , Aicart Michel 
Published: April 2009

AbstractLe dicarbométhoxy‐3,4 furanne porteur d'un groupement acétonyl ou phénacyl en position 2 est préparé par pyrolyse de l'adduit diénique semihydrogéné entre acétylènedicarboxylate de méthyle et acéeonyl‐2 ou phénacyl‐2 furanne. La condensation du composé acétonylé avec la tryptamine conduit aux dérivés d'un nouvel hétéroyohimbane à noyau furannique: l'indolo[2,3‐a]furo[3,2‐g]quinolizine, précurseur potentiel du yohimbane.Les cétodiacides furanniques obtenus par saponification sont à la base d'une nouvelle voie d'accés aux deérivés de la furo[3,2‐c]pyrone‐4 et de la furo[3,2‐c]pyridine.
The stereochemistry of sulfonium ylides derived from 9‐alkylidenethioxanthenes– The relationship between ring inversion and S+C− bond rotation
Authors: Kluba M. , Harwood J. , Casey P. K. , Ternay A. L. 
Published: April 2009

AbstractA series of sulfonium ylides has been prepared by the reaction of 9‐alkylidenethioxanthenes with dimethyl diazomalonate. The e' electron pair on sulfur is more efficient than the a' in trapping the “carbenes” generated by copper(II) catalyzed decomposition of diazo compounds. Consequently, e' ylides are the kineti‐cally‐controlled reaction products. Varying the C2 substituent does not alter this.Sulfides and sulfonium ylides containing the isopropylidene moiety do not undergo rapid ring inversion. Rotation about the S+C− bond occurs in the pseudo‐axial conformation but not the pseudo‐equatorial. The use of the anisochronicity of portions of the malonylide fragment as a criterion for heterocyclic ring inversion is presented. It is suggested that the sulfoxides of phenothiazine, phenoxathiin, thianthrene, and related sulfoxides, undergo rapid ring inversion.
Reactions of 2‐aminooxazoles and 2‐aminothiazoles with dienophiles. Isolation of stable diels‐alder adducts
Authors: Crank George , Khan Humaid R. 
Published: April 2009

AbstractRoom temperature reaction of 2‐aminooxazole 1 and its 4‐ and 4,5‐substituted derivatives, with dimethyl acetylenedicarboxylate gave good yields of Diels‐Alder adducts 2, isolated as stable crystalline compounds. A competing process produced oxazole[3,2‐a]pyrimidines 3, also in good yield. Minor products were also identified. 2‐Amino‐4‐methylthiazole (6) reacted in a similar manner and gave the Diels‐Alder adduct 7 and a thia‐zolo[3,2‐a]pyrimidine 8 as main products with a lesser amount of a thiazole [3,2‐d][1:3]diazepine (9). The aminooxazoles reacted with olefinic dienophiles to give pyridine derivative, formed by breakdown of the original unstable adducts.
Synthesis and properties of 3‐nitrosocarbazole
Authors: Kyziol Janusz B. 
Published: April 2009

AbstractThe synthesis of 3‐nitrosocarbazole (I) by the Fischer‐Hepp rearrangement of 9‐nitrosocarbazole has been described. The resistance of I to oxidation provides evidence that it cannot be the intermediate in the conversion of 9‐nitrosocarbazole to the C‐nitro compounds. It has also been shown that I and its derivatives cannot be synthesized by the action nitrosyl chloride on carbazoles. Methylation of I yields 9‐methyl‐3‐nitrosocarbazole, 9,9′‐dimethyl‐3‐azocarbazole and 9,9′‐dimethyl‐3‐azoxycarbazole as the main products. The mechanism of this disproportionation process has been proposed. The spectral data of I are given.
Novel oxidation of tetrasubstituted furans by pyridinium chlorochromate
Authors: Akhtar Mohammed Shamim , Seth Manju , Bhaduri Amiya Prasad 
Published: April 2009

AbstractA novel oxidation of tetrasubstituted furans with pyridinium chlorochromate has been studied and this has led to a convenient synthesis of 4‐acetoxy‐3‐acetyl‐ or methoxycarbonyl‐4‐substituted phenylbut‐3‐en‐2‐one.
Reaction products of 2‐aminobenzenethiol with some β‐diketones
Authors: Alyea Elmer C. , Malek Abdul 
Published: April 2009

Abstract2‐Aminobenzenethiol undergoes condensation reactions with several β‐diketones (CH3, CF3 and C6H5 substituents) to form benzothiazolines. Conversion to benzothiazines and benzothiazoles occurs in some instances, as documented by the isolation and spectroscopic characterization of the products.
Nucleophilic substitution of 1,2,4‐triazines
Authors: Huang Jim J. 
Published: April 2009

AbstractThe reaction of 3‐(methylthio)‐5‐carbethoxy‐1,2,4‐triazine (5) with ammonia was found to yield products from not only ammonia but also methanethiolate displacements. An account of the transformations and the products observed is given. The 3‐position of 3,6‐bis(methylthio)‐5‐carbamoyl‐1,2,4‐triazine (7) was shown to be more reactive than the 6‐position toward nucleophilic substitution. Reduction at the 4,5 positions of triazine 5 occurred upon treatment with methanethiol under basic and neutral conditions.
Synthesis of 2‐substituted 3‐oxoisothiazolo[5,4‐b]pyridines
Authors: Monge A. , Martinez‐Merino V. , Fernandez‐Alvarez E. 
Published: April 2009

AbstractStarting with 2‐chloro‐3‐pyridinecarboxylic acid 1, three different routes to prepare 3‐oxoisothiazolo‐[4,5‐b]pyridines 10 were studied.
Cyclocondensation of 2‐hydrazinoperimidine with diethyl oxalate and ethyl pyruvate
Authors: Liu Kang‐Chien , Chen Hsiu‐Ho 
Published: April 2009

AbstractRefluxing 2‐hydrazinoperimidine (1) with excess amount of diethyl oxalate (2a) gave ethyl 1H‐1,2,4‐triazolo[4,3‐a]perimidine‐3‐carboxylate (4a) in 84% yield. On the other hand, heating 1 with ethyl pyruvate (2b) in glacial acetic acid afforded 3‐methyl‐1,2,4‐triazino[4,3‐a]perimidin‐4(1H)‐one (6b) in 92% yield. Structures of the products were investigated by spectral and elemental analysis.
Synthesis of selected 3‐substituted‐pyrimido[5,4‐e]1,2,4‐triazine‐5,7‐diamines as potential folate antagonists
Authors: Werbel Leslie M. , Elslager Edward F. , Johnson Judith L. 
Published: April 2009

Abstract3‐(Anilinomethy1) 3‐[(arylthio)methy1]pyrimido[5,4‐e]‐1,2,4‐triazine‐5,7‐diamines were prepared by ring closure of 6‐hydrazino‐4‐[(phenylmethy1)thio]‐2.5‐pyrimidinediamine. these nonclassical analogs of known potent dihydrofolate reductase inhibitors were inactive against malarial infections in mice and L1210 leukemia in vitro.
Synthesis of N4‐(5‐methoxy‐7‐benzofuranyl)‐1,4‐pentanediamine, an oxygen isostere of primaquine
Authors: Johnson Judith L. , Werbel Leslie M. 
Published: April 2009

AbstractN4‐(5‐Methoxy‐7‐benzofuranyl)‐1,4‐pentanediamine, an oxygen isostere of primaquine was synthesized and found devoid of antimalarial activity.
Synthesis of novel N‐(1,2,3,7,8,9,9a,9b‐octahydro‐3‐(phenylmethyl)‐5H‐dipyrrolo [1,2‐c,3,2‐e]pyrimidine‐5‐ylidene)benzenamine derivatives
Authors: Matthews Donald P. 
Published: April 2009

AbstractN‐(1,2,3,7,8,9,9a,9b‐Octahydro‐3‐(phenylmethyl)‐5H‐dipyrrolo [1,2‐c,3,2‐e]pyrimidine‐5‐ylidene)benzenamine were prepared in moderate yields from the novel intermediate 1′‐(phenylmethyl)‐(2,3′‐bipyrrolidin)‐2‐one 4.
Chemistry of thienopyridines. XXXIV. Mass spectral fragmentation patterns of some secondary amines and related imines
Authors: Klemm L. H. , White D. V. 
Published: April 2009

AbstractThe mass spectra of some secondary amines and aldimines in the thieno[2,3‐b]pyridine (3) system are presented. α, α‐Bis(4‐thieno[2,3‐b]pyridylamino)toluene (1) undergoes (a) electron impact‐induced dissociation at 80° to give the spectrum of 4‐amino‐3 (3b) and (b) thermal dissociation at 200° to give a composite spectrum of 3b and its benzylidene derivative. Spectra of benzylamino and dimethylaminobenzylamino derivatives of 3 are dominated by benzyl‐type fragments, while benzylideneimino derivatives show more varied fragmentation.