bluuebunny/crossref_metadata_2025 huggingface dataset:
Direct nitration of aldehyde arylhydrazones and the use of the products in the synthesis of some heterocyclic compounds
Authors: Shawali Ahmad S. , Hassaneen Hamdi M. , Sherif Sherif M.
Published: March 2009

Direct nitration of substituted benzaldehyde p‐nitrophenylhydrazones 1 gave α‐nitroarylidene‐p‐nitrophenylhydrazines 2. Reactions of 2 with nucleophiles result in displacement of the nitrite. Treatment of 2 with potassium thiocyanate gave 5‐imino‐1,3,4‐Δ2‐thiadiazolines 10. Reactions of 2 with carbanions of active methylene compounds yielded the pyrazole derivatives 15–20. 1,3‐Dipolar cycloadditions of 2 onto acrylonitrile and benzalacetophenone afforded the expected cycloadducts 21 and 22, respectively.
Polyazasteroids. III. 1,2,4‐triazolo[3,4‐a]benzo[f]isoquinoline. Synthesis of the diazaphenanthrene alkaloid perlolidine and its 1,8‐phenanthroline isomer
Authors: Lalezari I. , Nabahi S.
Published: March 2009

A series of 1,2,4‐triazolo[3,4‐a]benzo[f]isoquinolines, which constitutes a new class of polyazasteroidal compounds, were synthesized. A simple synthesis of the diazaphenanthrene alkaloid perlolidine as well as 1,8‐phenanthrolin‐7‐(8H)one is reported.
The synthetic utility of heteroaromatic azido compounds. Part VI. Preparation of some 1H‐1,2,3‐triazolo[1,5‐a]thieno[3,2‐d]pyrimidines
Authors: Westerlund Christer
Published: March 2009

Some 1,2,3‐triazolo[1,5‐a]thieno[3,2‐d]pyrimidines have been prepared by the reaction of active methylene nitriles with 3‐azido‐2‐substituted thiophenes. Thus, for example the 3‐carboxy derivative 5 was prepared by condensation of 3‐azido‐2‐formylthiophene dimethyl acetal (1) with ethyl cyanoacetate, followed by intramolecular cyclization. Decarboxylation of 5 led to the unsubstituted parent compound 6. The structure of the triazole‐fused compounds is discussed.
The chemistry of 2H‐1,3‐benzoxazine‐2,4‐(1H)dione (isatoic anhydride). 8. A one step synthesis of the quinindoline ring system and related compounds
Authors: Coppola Gary M.
Published: March 2009

The reaction between N‐substituted isatoic anhydrides and the carbanion generated from 3‐methylthio‐oxindole to produce the quinindoline ring skeleton is discussed. Analogous reactions of azaisatoic anhydride 6 and tricyclic anhydride 8 produces the 4‐aza analog 7 and pentacycle 9. Some spectral data is also described.
O‐ethyl thiocarbamates. A convenient route to 2‐aryliminoimidazolidines
Authors: Reynaud Pierre , Brion Jean‐Daniel , Davrinche Catherine , Dao Phan‐Chi
Published: March 2009

The reaction of N‐aryl thionocarbamates and ethylenediamine lead to the corresponding 2‐arylimino‐imidazolidines, whose structure in pharmacology is well known. But, the behaviour of the N‐alkyl thionocarbamates is quite different under operative conditions and these compounds afford with ethylenediamine, to 2‐(2′‐aminoethylamino)‐Δ2‐imidazoline, according to a mechanism which is discussed.
Structure elucidation of a condensation product of 4‐aminopyrrole derivatives and dicyclohexylcarbodiimide
Authors: Bialer Meir , Yagen Boris , Mechoulam Raphael
Published: March 2009

The chemical structure of the two condensation products of dicyclohexylcarbodiimide (DCC) with the precursors of the mono‐pyrrole homologues of distamycin and with the mono and tri‐pyrrole homologues of congocidine were established. The two products isolated were proven to be condensation products between 4‐aminopyrrole derivatives and dicyclohexylcarbodiimide (DCC).
Chemical and biological modification of bleomycin, an antitumor antibiotic
Authors: Takita Tomohisa , Maeda Kenji
Published: March 2009

Dedicated to Professor John C. Sheehan on the occasion of his sixty‐fifth birthday.

Chemical and biological modifications of bleomycin, an antitumor glycopeptide antibiotic, have been achieved by three procedures analogous to the modifications of penicillin.
On the naure of the intermediate in liquid‐phase sulfonations of olefins‐A retrospective evaluation
Authors: Zoller Uri
Published: March 2009

A six‐membered ring carbyl sulfate rather than a four‐membered β‐sultone is suggested as the principal intermediate in liquid‐phase sulfonations of olefins.
Total synthesis of actinomycin D(C1) via a ring‐opening reaction of aziridine
Authors: Okawa K. , Nakajima K. , Tanaka T.
Published: March 2009

Actinomycin D(C1) has been synthesized by a route involving the ester formation between two peptide fragments, (2S,3S)‐1‐(2‐nitro‐3‐benzyloxy‐4‐methylbenzoyl)‐3‐methyl‐2‐aziridine‐carbonyl‐D‐valylproline t‐butyl ester and N‐benzyloxycarbonylsarcosyl‐N‐methylvaline, via a ring‐opening reaction of aziridine. Cyclization, followed by reduction and oxidation, gave actinomycin D(C1). The synthetic actinomycin D(C1) was indistinguishable from natural substance with respect to physical properties and biological activity.
Recent discoveries in the search for non‐opiate analgetics
Authors: Johnson M. Ross , Milne George M.
Published: March 2009

A novel phenanthridine, nantradol (1), resulted from a search to dissect out analgetic activity from the cannabinoid molecule. Nantradol possesses two to seven times greater potency than morphine across a battery of analgetic tests. Despite this morphine‐like profile, nantradol does not bind to the opiate receptor. Nantradol has a total of five asymmetric centers and was studied as a 50:50 mixture of two diastereomers, both of which possess thetrans6a, 10a stereochemistry and have β‐oriented substituents at positions 6 and 9. Evidence is provided that, in common with the opiates, the analgetic actions of nantradol are stereospecific, the majority of the activity residing in a single levorotatory isomer. The stereospecificity and potency of the analetic effects of the nantradol series suggests a highly specific interaction at an as yet unidentified receptor.
Hetarylpyrazoles. II. Reactions of pyrazol‐l'‐ylpyridines
Authors: Khan Misbahul Ain , Pinto Alvaro Augusto Alves
Published: March 2009

Pyrazol‐l'‐ylpyridines undergo electrophilic substitution reactions (bromination, chlorination, and nitration) preferentially in the pyrazole ring. There is some evidence of the mutual influence of the pyrazole and the pyridine ring on the reactivity of the system. Some modifications of the substituents were also carried out. A dihydro derivative of a new ring system, pyrazolo[1′,2′‐a]pyrido[2,1‐c][l,2,4]triazine was also obtained.
The crystal structure of a trisisoxazole compound: 3‐(3‐Methyl‐5‐isoxazolyl)methyl‐5‐(3‐methyl‐5‐isoxazolyl)methylisoxazole
Authors: Albinati A. , Brückner S. , Malpezzi L. , Meille S. V.
Published: March 2009

The crystal structure of a trisisoxazole derivative is described. The crystals are monoclinic, space group P21/c (Z = 4) with cell dimensions: a = 8.846(4), b = 26.688(7), c = 9.081(4) Ä, β = 142.82(7)0. The structure was refined by full matrix least squares to a final R of 0.060. The molecule is non‐planar and the bond lengths and angles are in the expected range for isoxazole derivatives.
Transformations in the dibenzo[a,d]cycloheptene series
Authors: Coppola Gary M. , Hardtmann Goetz E. , Koletar Gabor , Kroin Stanley
Published: March 2009

The synthesis of 5‐aminomethyl‐5‐hydroxy‐5H‐dibenzo[a,d]cycloheptene derivatives 3 was accomplished by two separate routes. The first route involves the reaction of 4 with Corey's Reagent followed by reaction with either amines or hydrazines. The reaction products with hydrazines (e.g. 6) were hydrogenolyzed, either with hydrogen in the presence of platinum, or with hydrazine in the presence of Raney nickel to yield 3. The second route to these compounds (3) proceeds by a Reformatsky reaction on 4 followed by acid‐hydrazide formation and Curtius degradation of 8 to afford spirooxazolidones 9. Compounds 9 can be alkylated on nitrogen (10), and either 9 or 10 hydrolyzed to give the target compounds 3.
Studies in the synthesis and interconversion of isomeric triazolothienopyrimidines
Authors: Shishoo C. J. , Devani M. B. , Ullas G. V. , Ananthan S. , Bhadti V. S.
Published: March 2009

4‐Hydrazinothieno[2,3‐d]pyrimidines were cyclized with triethyl orthoformate and formic acid to give 1,2,4‐triazolo[4,3‐c]thieno[3,2‐e]pyrimidines and 1,2,4‐triazolo[2,3‐c]thieno[3,2‐e]pyrimidines depending on the reaction conditions employed.
A reinvestigation of the stevens rearrangement of 1‐benzyl‐1,3,4‐trimethyl‐1,2,5,6‐tetrahydropyridinium salts
Authors: Bosch Joan , Rubiralta Mario , Domingo Antonio , Sistaré José
Published: March 2009

Authentic samples of 1,3,3‐trimethyl‐2‐(3,4,5‐trimethoxyphenyl)‐4‐methylenepiperidine (Ia) and 2‐(p‐chlorophenyl)‐1,3,3‐trimethyl‐4‐methylenepiperidine (Ib) are prepared by Mannich condensation between 4‐methyl‐1‐methylamino‐3‐pentanone hydrochloride (VI) and an aromatic aldehyde, followed by a Wittig reaction on the resulting 4‐piperidone. Comparing the physical and spectroscopic properties of Ia and Ib with those of the methylene derivatives IIa and IIb obtained as by‐products in the Stevens rearrangement of 1‐benzyl‐1,3,4‐trimethyl‐1,2,5,6‐tetrahydropyridinium salts IIIa and IIIb, respectively, it is shown that the assignment previously made for IIa and IIb is incorrect. Spectroscopic analysis (ir, 1H nmr, 13C nmr, ms) of these compounds and of its hydrogenation products VIII allows the structural and stereochemical assignment of 11a as cis‐3‐isopropenyl‐1,3‐dimethyl‐2‐(3,4,5‐trimethoxyphenyl)pyrrolidine and of IIb as cis‐2‐(p‐chlorophenyl)‐3‐isopropenyl‐1,3‐dimethylpyrrolidine. The formation of these rearrangement products is mechanistically interpreted as a Stevens [3,2] type process.
New synthesis of 7‐bromo‐1, 3‐dihydro‐3‐hydroxy‐5‐(2′‐pyridyl)‐2H‐1,4‐benzodiazepin‐2‐one
Authors: Kovač Tomislav , Belin Branka , Fajdiga Tatjana , Šunjić Vitomir
Published: March 2009

A new synthesis of 7‐bromo‐1,3‐dihydro‐3‐hydroxy‐5‐(2′‐pyridyl)‐2H‐1,4‐benzodiazepin‐2‐one (5) is described. Starting from bromazepam (3), C(3) acylation with lead tetraacetate/potassium iodide in acetic acid affords4, while its mild hydrolysis according to our recently described method (5) gives5. Improved hexamine cyclization of1into3,viaquaternary hexaminium salt2, is discussed, and identification of the intermediates7and8is performed. Compound5undergoes on melting, or on brief heating in glacial acetic acid, the thermal rearrangement into quinazolin‐2‐aldehyde (13), the structure of which is confirmed by oxidation into the ester14, which in turn was hydrolyzed to the acid15. The same compound (5) rearranges on heating with manganese(III) acetate in acetic acid into the 3‐amino‐2‐quinolone derivative6. On heating in glacial acetic acid in the presence of lead tetraacetate/potassium iodide (or iodine), compound4, in addition to giving the aldehyde13, ester14and acid15rearrangement products, affords 1,2‐dihydroquinazolin‐2‐carboxylic acid16.
Reissert compound studies. XXXIX. A novel approach to the berbine and 6‐azaberbine systems and related derivatives of ellipticine
Authors: Veeraraghavan Seshadri , Popp Frank D.
Published: March 2009

A new synthetic method for the construction of the berbine, 6‐azaberbine, and indoloberbine ring skeletons is reported. Treatment of heterocyclic bases such as isoquinolines, phthalazines, and ellipticine with 2‐chloromethylbenzoyl chloride and trimethylsilyl cyanide gave the corresponding Reissert compounds. Treatment of these Reissert compounds with sodium hydride resulted in intramolecular cyclization with loss of hydrogen cyanide.
Fused s‐triazino heterocycles. VIII. 1,3,4,6,9b‐pentaazaphenalenes. Reactions of a methyl and bromomethyl side chain
Authors: Shaw John T. , Brotherton Christine E. , Moon Robert W. , Coffindaffer Timothy W. , Miller Deborah A.
Published: March 2009

Enhanced reactivity of the methyl group of 2‐t‐butyl‐5‐methyl‐1,3,4,6,9b‐pentaazaphenalene allowed acetic anhydride‐catalyzed condensation reactions with several aromatic aldehydes, and base‐catalyzed alkylation reactions with several alkyl halides to take place, albeit in low yields. Of the many nucleophiles tried, only salts of carboxylic acids, in the presence of 18‐crown‐6, were able to displace bromine from 2‐(bromomethyl)‐5‐methyl‐1,3,4,6,9b‐pentaazaphenalene.
Derivatives of 2,3,8,9‐tetrahydro‐3‐oxo‐1H‐benz[de]isoquinoline‐1,9a‐(7H)dicarboximide
Authors: Campaigne E. , Yodice Richard
Published: March 2009

The synthesis of a series of derivatives of 2,3,8,9‐tetrahydro‐3‐oxo‐1H‐benz[de]isoquinoline‐1,9a‐(7H)dicarboximide (1) are described. Alkylations and thionations of 1 produced a variety of interesting heterocycles. In addition, triazole and triazolone rings were fused to 1 to produce novel compounds. These structures were of interest as potential anticonvulsants.
Synthesis of 1‐alkyl and 1,3‐dialkyl‐2‐benzimidazolones from 1‐alkenyl‐2‐benzimidazolones using phase‐transfer catalysis technique
Authors: Vernin Gaston , Domlog Hicham , Siv Chan , Metzger Jacques , El‐Shafei Ahmed Kamal
Published: March 2009

A general synthetic route to 1‐alkyl and 1,3‐dialkyl‐2‐benzimidazolones from 1‐alkenyl‐2‐benzimidazolones using phase‐transfer catalysis conditions is described.
A new synthesis of 6‐(alkyl)amino‐3‐aryl(alkyl)‐1,2,4,5‐tetrazines
Authors: Counotte‐Potman Anda , Van Der Plas Henk C.
Published: March 2009

A new method for the preparation of 6‐(alkyl)amino‐3‐aryl(alkyl)‐1,2,4,5‐tetrazines is described. Dissolving 3‐aryl(alkyl)‐1,2,4,5‐tetrazines in liquid ammonia or a primary aliphatic amine at −35° to −40°, followed by addition of potassium permanganate gives the title compounds in reasonable to excellent yields.
Etude de l'oxydation de tétrahydroisoquinoléinols‐4 diméthoxylés en 6,7 ou 7,8, et sur la réactivité du carbonyle de la tétrahydroisoquinolone‐4 diméthoxylée en 6,7
Authors: Lesèche Bernard , Gilbert Jacques , Viel Claude
Published: March 2009

Préparation des tétrahydroisoquinoléinols‐4 mentionnés ci‐dessus, et étude de l'oxydation de ceux‐ci au moyen de divers réactifs: oxydations chromiques, par les bromamides, le diméthyl‐sulfoxyde, la réaction d'Oppenauer. Seule cette dernière a conduit aux tétrahydroisoquinolones‐4 cherchées. A l'exception du bromoacétamide et de l'Oppenauer, tous les autres réactifs fournissent une trioxo‐1,3,4 tétrahydroisoquinoléine. Le comportement de la tétrahydroisoquinolone‐4 diméthoxylée en 6,7, vis‐à‐vis de certains réactifs spécifiques de la fonction carbonyle est étudié.
Chemistry of the phenoxathiins and isosterically related heterocycles. XIV. Total assignment of the 13C‐Nmr spectrum of pyrrolo[3,2,1‐kl]phenothiazine
Authors: Gampe Robert T. , Martin Gary E. , Pinto Angelo C. , Hollins Richard A.
Published: March 2009

Total assignment of the 13C‐nmr spectrum of the novel tetracyclic phenothiazine, pyrrolo[3,2,1‐kl]phenothiazine is described. Assignments were determined from model systems, 1H‐13C spin‐coupling behavior in conjunction with selective excitation techniques and spin‐lattice (T1) relaxation measurements. The anisotropic reorientation of this ring system via a principal axis passing through the center of the molecule, which provides a qualitative basis for signal discrimination, is also discussed.
1‐(1‐aryl‐3‐ethylthiocarbamido)‐4‐arylaminothiocarbonyl)‐ piperazines as possible anticonvulsants
Authors: Singh Shiva P. , Parmar Surendra S.
Published: March 2009

Several 1‐(1‐aryl‐3‐ethylthiocarbamido)‐4‐(arylaminothiocarbonyl)piperazines were synthesized as possible anticonvulsants. These 1,4‐disubstituted piperazines were characterized by their sharp melting points and elemental and spectral analyses.
Ortho effects in 3‐methyl‐5‐(o‐r‐styryl)‐4‐aminoisoxazoles on electron impact. III
Authors: Martínez R. , Cortés E.
Published: March 2009

Electron impact mass spectra of eight of the title compounds are discussed. Based on our data a mechanism for the formation of the m/e 91 ion is proposed. Fragmentation pathways have been confirmed by measurement of the metastable peaks.
Benzo[h]cinnolin
Authors: Bluhm Thorsten
Published: March 2009

The synthesis of benzo[h]cinnolin (3) is reported. Its spectroscopic properties (uv, luminescence, pmr, ms) are similar to the other diazaphenanthrenes containing a diazine ring. The lowering of the basicity of 3 compared with a monoazaphenanthrene like other diaza‐aromatic compounds appears to be due to an electrostatic field effect and not to an inductive effect.
Amidrazones. 6. Synthesis of 1,2,4‐thiadiazoles by thermolysis of N3‐thiocarbamoylamidrazone ylides
Authors: Smith Richard F. , Feltz Timothy P.
Published: March 2009

Reaction of N3‐unsubstituted amidrazone ylides (1a and 1b) with alkyl or aryl isothiocyanates gives N3‐thiocarbamoylamidrazone ylides (2). Thermolysis of 2 gives 3‐alkyl(or aryl)‐5‐alkyl(or aryl)amino‐1,2,4‐thiadiazoles (3a‐i).
Selenium‐sulfur analogs. 4. Synthesis and characterization of (±)‐β‐(2‐amino‐1,3‐selenazol‐4‐yl)alanine
Authors: Hanson Robert N. , Davis Michael A.
Published: March 2009

The novel amino acid (±)‐β‐(2‐amino‐1,3‐selenazol‐4‐yl)alanine 4a was prepared from selenourea and 1,3‐dichloropropan‐2‐one via a four‐step synthetic sequence. Nuclear magnetic resonance analysis indicated a downfield chemical shift of δ 0.29 to 0.30 and δ 0.57 for the C5‐proton of the protonated 2‐amino‐and 2‐acetamido‐1,3‐selenazoles respectively compared with the analogous thiazoles. The infrared spectra of the selenazole and corresponding thiazole compounds were virtually identical.
The photochemical reactions of 5H‐benzo[a]phenoxazin‐5‐one with alkylthiols and thiophenol
Authors: Ueno Yoshio , Takeuchi Yutaka , Koshitani Jinya , Yoshida Takatoshi
Published: March 2009

6‐Alkylthio‐ and 6‐phenylthio‐5H‐benzo[a]phenoxazin‐5‐ones have been synthesized by the photochemical reaction of 5H‐benzo[a]phenoxazin‐5‐one with alkylthiols and thiophenol.
Tetrahydro‐2‐thioxo‐2H‐1,3,5‐thiadiazin‐4‐ones and their derivatives representing a novel heterocyclic ring system
Authors: Bélai Iván , Sohár PÁL , Maekawa Kazuyuki , Párkányi László , Matolcsy GyÖRgy
Published: March 2009

The cyclization reaction between N‐substituted dithiocarbamates (1) and N‐substituted N‐chloromethylcarbamoyl chlorides (2) gives 3,5‐disubstituted tetrahydro‐2‐thioxo‐2H‐1,3,5‐thiadiazin‐4‐ones (3). In order to decide among the theoretically possible structures 3‐5, the compounds 6a,b, containing a thioxo group instead of an oxo group as in 3a,b, as well as the S‐oxide derivative of 3a was also established by X‐ray structure determination.
Synthesis and characterization of some bifunctional 2b:2:1 cryptands
Authors: Gansow Otto A. , Kausar A. Rashid , Triplett Kelly B.
Published: March 2009

Methods for the synthesis of aromatic substituted diaza‐polyoxamacrobicyclic compounds (benzocryptands) are described. New synthetic routes to cryptand precursors are developed and improvements in eryptand synthesis discussed and employed to prepare some bifunctional cryptands.
Amidrazones. VII. Formation of s‐triazines by thermolysis of N1‐benzyl‐substituted amidrazone ylides
Authors: Smith Richard F. , Soelch Richard R. , Feltz Timothy P. , Martinelli Michael J. , Geer Susan M.
Published: March 2009

The preparation of ylides of the general structure magnified image is described. Thermolysis of 14a (R = CH3, R' = H, Ar = C6H5) gave dimethylamine and 2,4‐dimethyl‐6‐phenyl‐s‐triazine. Thermolysis of ylides 14b (R = C6H5; R' = CH3, Ar = C6H5) and 14c (R = C6H5, R' = CH3, Ar = p‐tolyl) gave dimethylamine, ArCH = NCH3 and 1‐methyl‐2‐Ar‐4,6‐diphenyl‐1,2‐dihydro‐s‐triazines (19a,b). Triazines 19a and 19b were also prepared by condensation of N‐methylbenzamidine with benzaldehyde and p‐tolualdehyde, respectively. Thermolysis of 14d(R = C6H5, R1 = CH2C6H5,Ar = C6H5) gave 1‐benzyl‐2,4,6‐triphenyl‐1,2‐dihydro‐s‐triazine (19c) and N‐benzylidenebenzylamine. Mechanistic aspects of these reactions are discussed.
New synthesis of chalcogenolactones. 1H,3H‐benzo[c]selenophen‐1‐one, 1H,3H‐benzo[c]tellurophen‐1‐one and the related 3,4‐dihydro‐1H‐2‐benzoselenin‐1‐one and 3,4‐dihydro‐1H‐2‐benzotellurin‐1‐one
Authors: Loth‐Compère M. , Luxen A. , Thibaut Ph. , Christiaens L. , Renson M. , Guillaume M.
Published: March 2009

The synthesis of three new basic heterocyclic systems namely, 1H,3H‐benzo[c]tellurophen‐1‐one (2‐tellurophthalide), 3,4‐dihydro‐1H‐2‐benzoselenin‐1‐one (3,4‐dihydro‐2‐isoselenocoumarin) and 3,4‐dihydro‐1H‐2‐benzotellurin‐1‐one (3,4‐dihydro‐2‐isotellurocoumarin), is reported through the cyclisation of o‐(bromoalkyl)benzoyl chlorides.
Reactions of some benzofuran derivatives with amides, nitriles and hydrazines
Authors: Abd el Rahman A. H. , Kandeel E. M.
Published: March 2009

When 6‐acetoacetyl‐5‐methoxy‐ (1b) and 5‐acetoacetyl‐6‐methoxy‐2,3‐diphenylbenzofuran (2b) were treated with cyanoacetamide, the corresponding pyridinecarbonitriles were obtained. Compounds 1b and 2b reacted with ethyl cyanoacetate in the presence of ammonium acetate to give the benzofuranyl‐pyrone derivatives. This reaction, when carried out in presence of diethylamine, led to the formation of furochromones. Hydrazine hydrate, phenylhydrazine and semicarbazide hydrochloride reacted with 1b and 2b with the formation of the corresponding pyrazoles. The corresponding isoxazole derivatives were formed by the reaction of 1b and 2b with hydroxylamine hydrochloride.
Reactions of hydrazidoyl chlorides with sodium N,N‐dialkyldithiocarbamates
Authors: Kaugars Girts , Rizzo Victor L.
Published: March 2009

The reaction of N‐arylbenzhydrazidoyl chlorides (1) with sodium N,N‐dialkyldithiocarbamates yields the hydrazone derivatives 2, which react further to form 4 unless the reaction sites are sterically crowded.
The Dimer of Δ1(8)‐Dehydropyrrolizidine and Its Reduction
Authors: Sumoto Kunihiro , Fujii Skinichiro , Yamashita Osamu , Somehara Takao , Miyano Seiji
Published: March 2009

The structure and reductions of the dimer of Δ11(8)‐dehydropyrrolizidine are described.
Reductive dimerization of 1,3,4,6‐tetramethyl‐2‐phenylpyrimidinium bistetrafluoborate
Authors: Douglass James E. , Bumgarner David L.
Published: March 2009

The diquaternary salt, 1,3,4,6‐tetramethyl‐2‐phenylpyrimidinium bistetrafluoborate (3) was found to undergo reductive dimerization in the presence of zinc to afford the diquaternary salt 6.
Action du dicétène sur la benzoylcyanamide: La benzoylamino‐2 méthyl‐6 oxazine‐1,3 one‐4
Authors: Perronnet Jacques , Girault Pierre , Taliani Laurent
Published: March 2009

Le dicétène opposé à la benzoylcyanamide donne lieu à une cycloaddition 1,4 avec le groupement nitrile de cette dernière. Le produit résultant est une oxazine‐1,3 one‐4 qui se prěte à diverses réactions d'ouverture ou de réarrangement, initiées par la grande réactivité de son sommet 2.
Synthesis of 3‐Coumaryl Phenyl Sulfones or Sulfoxides
Authors: Merchant J. R. , Shah P. J.
Published: March 2009

An unambiguous synthesis of a number of 3‐coumaryl phenyl sulfones or sulfoxides have been described which were obtained by the oxidation of the corresponding sulfides with hydrogen peroxide. The sulfides were prepared by the Perkin‐Oglialore reaction of o‐hydroxyaldehyde with the sodium salt of different S‐phenyl thioacetic acids. The sulfones did not exhibit any appreciable antitubercuious activity in the preliminary screening tests.
New Synthesis of (±)‐5‐hydroxymarmesin, biogenetic precursor of the skin photosensitizing agent bergapten (5‐MOP)
Authors: Rodighiero P. , Manzini P. , Pastorini G. , Guiotto A.
Published: March 2009

A convenient synthesis is described of (±)‐5‐hydroxymarmesin, 4‐hydroxy‐2‐(1‐hydroxy‐1‐methylethyl)‐2,3‐dihydro‐7H‐furo[3,2‐g][1]benzopyran‐7‐one, a physiological intermediate in the biogenetic pathway of 5‐O‐alkylfurocoumarins. The synthesis was achieved by a regiospecific 6‐C isoprenylation of 5,7‐diacetoxy‐coumarin; the 6‐C isoprenylated derivative is then submitted to an oxidative cyclization obtaining mainly the title compound together with its angular isomer.
Reinvestigation of the stevens rearrangement of 1‐benzyl‐1,3,4‐trimethyl‐1,2,5,6‐tetrahydropyridinium salts. II. Synthesis of 2‐aryl‐3‐isopropenyl‐1,3‐dimethylpyrrolidines
Authors: Bosch Joan , Rubiralta Mario
Published: March 2009

cis‐2‐Aryl‐3‐isopropenyl‐1,3‐dimethylpyrrolidines Ha and IIb have been synthesized by an unambiguous way, thus confirming the structure of the methylene derivatives obtained as by‐products in the Stevens rearrangement of 1‐benzyl‐1,3,4‐trimethyl‐1,2,5,6‐tetrahydropyridinium salts Ia and Ib. The synthesis is based on the acid‐induced intramolecular cyclization between an iminium salt and the α‐position of a ketal group. Thus, condensation between amino ketal XXI, prepared via Gabriel synthesis from 5‐chloro‐3‐methyl‐2‐pentanone, and the appropriate aldehyde afforded imines XXI. Their treatment with dry hydrogen chloride followed by acid hydrolysis and methylation gave 3‐acetylpyrrolidines IV, which were transformed into the isopropenyl derivatives II by reaction with methyl‐lithium and further dehydration.
Reactions of o‐aminonitriles with isocyanates. 2. A facile synthesis of imidazo[1,2‐c]quinazoline‐2,5‐(3H,6H)dione
Authors: Papadopoulos Eleftherios Paul
Published: March 2009

Anthranilonitrile reacts with ethyl isocyanatoacetate to form 2‐(3‐ethoxycarbonylmethylureido)benzonitrile (3b) which, upon heating, or treatment with a base, undergoes a double cyclization to yield imidazo[1,2‐c]‐quinazoline‐2,5‐(3H,6H)dione (5) in excellent yield. In the presence of acid, 3b is converted into 1,4‐dihydro‐2,4‐dioxo‐3‐(2H)quinazolineacetic acid (11), or its ethyl ester (10). The action of concentrated sulfuric acid converts the adduct 13 of anthranilic acid and ethyl isocyanatoacetate into 2‐ethoxycarbonyl‐methylamino‐4H‐3,1 ‐benzoxazin‐4‐one (14).
Ethynylogues du nicotinamide et de l'isoniazide
Authors: Babin Pierre , Dunoguès Jacques , Duboudin Françoise
Published: March 2009

Deux voies d'éthynylation ont été mises en oeuvre en série nicotinique et isonicotinique, ce qui a permis de préparer pour la première fois les éthynylogues du nicotinamide et de l'isoniazide: le (pyridyl‐3)propynyl amide 1 et le (pyridyl‐4)propynyl hydrazide 2, respectivement. Ces synthèses utilisent comme intermédiaire les chlorures de nicotinoyle et d'isonicotinoyle dont nous avons proposé une synthèse de mise en oeuvre beaucoup plus simple et rapide que les méthodes déjà existantes.
The preparation of the benzo[4,5]cyclohepta[1,2‐b]pyrazine and benzo[4,5]cyclohepta[1,2‐b]quinoxaline systems
Authors: Eberle Marcel K. , Kahle Gerard G.
Published: March 2009

Benzo[4,5]cyclohepta[1,2‐b]quinoxaIine 2, benzo[4,5]cyclohepta[1,2‐b]pyrazine 3a and benzo[4,5]cyclohepta[1,2‐b]quinoxaline 4 were prepared from 4,5‐benzotropolone and 1,2‐phenylenediamine, ethylenediamine and 1,2‐diaminocyclohexane, respectively. Compound 3a was methylated to 3b.
Mass spectral fragmentation pattern of 4,4′‐bipyridines. Part II. 4,4′‐oxybispyridine and 4,4′‐thiobispyridine
Authors: Rockley Jean E. , Summers Lindsay A.
Published: March 2009

The mass spectra of 4,4′‐oxybispyridine and 4,4′‐thiobispyridine are reported. In the former the base peak is due to the molecular ion and the fragmentation routes involve loss of H, CO, HCN, C2H2N and CsHO from the molecular ion as well as rupture of the central bonds. In the latter the base peak is also due to the molecular ion and the fragmentation routes involve loss of H, CS, S, HCN and C2HS as well as central bond rupture.
Investigation in tetronic acid ketoxime derivatives. Structure and beckmann rearrangement. Synthesis of 3‐acetamidotetronic acids
Authors: Gelin Suzanne
Published: March 2009

The structure and tautomeric equilibria of 3‐(1‐hydroxyiminoethylidene)tetronic acids have been investigated by 1H and 13C nmr spectroscopy. These oximes are convertible into 3‐acetamidotetronic acids.
The synthesis of “stretched‐out” analogs of lumazine, 6,7‐dimethyllumazine and 2‐amino‐5,6,7,8‐tetrahydro‐6,7‐dimethyl‐4‐pteridinone
Authors: Schneller Stewart W. , Christ William J.
Published: March 2009

The synthesis of pyrazino[2,3‐g]quinazolin‐2,4‐(1H,3H)dione (4) and its 7,8‐dimethyl derivative (5), as linear benzo‐separated lumazines, is reported. Also described is the preparation of 2‐amino‐6,7,8,9‐tetrahydro‐7,8‐dimethylpyrazino[2,3‐g]quinazolin‐4‐one (6), as a linear benzo‐separated analog of a synthetic cofactor for phenylalanine hydroxylase. All of the syntheses began with ethyl 2,4,5‐triaminobenzoate (8) and proceeded through the appropriate derivatives of ethyl 6‐aminoquinoxaline‐7‐carboxylate (9, 10, and 11) which were subsequently ring closed to 4, 5, and 6.
Condensation of β‐cyclocitral with benzaldehyde
Authors: Frank Arlen W.
Published: March 2009

β‐Cyclocitral 1b condenses with benzaldehyde in the presence of base catalysts giving the 2‐benzopyrans 4, 5 and 6, and in the presence of acid catalysts giving exclusively the aldehyde 7. The cyclocitrals 1a and 1b are both isomerized by strong base anion exchange resins, but their aldehyde‐protected derivatives 2 and 3 are not. Some tests used to characterize the aldehydes and their condensation products are described.
Pyrazoles. XVIII. Synthesis of a novel tripyrazolyl by two consecutive cine substitution reactions
Authors: Berbee Robertas P. M. , Habraken Clarisse L.
Published: March 2009

Preparation of the C‐N coupled tripyrazolyl VII, by two consecutive cine substitution reactions starting from 1,4‐dinitropyrazole and using pyrazole as a nucleophile, is described. Solvent dependent nitrations of 4‐nitro‐3(5)‐(1′‐pyrazolyl)pyrazole I are reported.
Cyclisation indolique selon bischler en presence d'acides de Lewis
Authors: Galons Hervé , Girardeau Jean‐François , Farnoux Claude Combet , Miocque Marcel
Published: March 2009

L'étude comparative de divers catalyseurs (acide chlorhydrique et acides de Lewis) dans la cyclisation des α‐aminocétones selon Bischler, a montré que le chlorure d'aluminium est le plus actif. L'isomérisation des indoles β en α s'observe lorsque les réactions sont conduites à température élevée; son mécanisme paraǐt différent de celui invoqué par la plupart des auteurs puisqu'elle ne porte pas sur les aminocétones mais sur les indoles.
Synthèse de polyéthers polycycliques. 1 Stéréosélectivité de l'hétérocyclisation d'alcools tétrahydrofurfuryliques γ,δ‐éthyléniques par les sels mercuriques
Authors: Amouroux Roger , Chastrette Francine , Chastrette Maurice
Published: March 2009

L'hétérocyclisation par oxymercuration intramoléculaire des (tétrahydrofuryl‐2)‐1 pentène‐4 ‐ols‐1, érythro et thréo, est réalisés de manière stéréosélective par l'acétate mercurique. Le méthyl‐2 tétrahydrofuryl‐5 tétrahydrofuranne obtenu après démercuration par réduction contient plus de 80% de l'isomère trans. En revanche la cyclisation par le chlorure mercurique conduit, après réduction, à un mélange d'isomères cis et trans en quantités voisines.
Structure and reactions of a thiazolino[3,2‐a]pyrimidine carbinolamine
Authors: Campaigne E. , Folting K. , Huffman J. C. , Selby T. P.
Published: March 2009

Ethyl 4‐chloroacetoacetate condenses with 4‐amino‐6‐hydroxy‐2‐pyrimidinethiol to yield ethyl 3‐hydroxy‐5‐oxo‐7‐aminothiazolino[3,2‐a]pyrimidin‐3‐acetate (3), and not ethyl 3‐hydroxy‐5‐amino‐7‐oxothiazolino[3,2‐a]‐pyrimidin‐3‐acetate, as previously reported. This compound reacts with ammonia to produce ethyl 4‐(6′‐amino‐4′‐oxo‐2′‐pyrimidinethiol)‐3‐aminocrotonate (8), the open chain structure of which accounts for the cyclization of 3 to the poly‐cyclic lactam, 6a‐hydroxy‐5,6,6a,7‐tetrahydro‐8‐thia‐1,4‐diazacycl[3.3.2]azine‐2,5‐dione, rather than the sterically more favorable lactone, when 3 was treated with triethylamine. Some other reactions of 3 are described, and the structures of 3 and 8 were comfirmed by single crystal X‐ray diffraction analysis.
Synthesis of New 1H‐indazole derivatives
Authors: Al‐Hajjar Farouk H. , Hamoud Hayat S.
Published: March 2009

Reactions of 3‐aryl‐1‐phenyl‐2‐propen‐1‐ones IIa‐d with ethyl phenylacetate (I) in the presence of sodium ethoxide under reflux for one hour gave only the corresponding 3,5‐diaryl‐2,4‐dibenzoyl‐6‐phenyl‐cyclo‐hexanones IIIa‐d. The reaction of these compounds with hydrazine hydrate afforded the corresponding 5‐benzoyl‐4,6‐diaryl‐3,7‐diphenyl‐1,4,5,6,7‐pentahydro‐1H‐indazole IVa‐d. The structures of the products were established by spectroscopic (ir, uv, nmr and mass spectra), single‐crystal X‐ray analysis and chemical evidence.
Synthesis of some 2,9‐disubstituted‐1,10‐phenanthrolines
Authors: Chandler Christopher J. , Deady Leslie W. , Reiss James A.
Published: March 2009

A series of symmetrically disubstituted compounds, with substituents linked to the ring through a carbon atom, has been prepared from 2,9‐dimethyl‐1,10‐phenanthroline. Nmr data are also reported.
Bipyrans for electrochemical studies. Preparation of polyene‐separated bipyrans and bithiopyrans
Authors: Reynolds G. A. , Chen C. H.
Published: March 2009

4,4′‐(But‐2‐ene‐1,4‐dienylidene)‐bi‐4H‐pyran and thiopyran derivatives were prepared by allowing the anion prepared from diethyl 4‐(2,6‐diphenyl‐4H‐pyranyI)phosphonate to react with 4‐pyranylidene butenaldehydes or the corresponding thiopyranylidene aldehydes. The oxidation potentials are compared of some bi‐4H‐pyrans and thiopyrans with zero, two, and four methenyl groups separating the heterocyclic nuclei.
1,3‐benzoxathioles. A simple synthesis of 3‐substituted 2‐hydroxybenzenethiols
Authors: Bernard Angela Maria , Cabiddu Salvatore , Piras Pier Paolo , Sotgiu Francesco
Published: March 2009

A convenient synthesis of 3‐substituted‐2‐hydroxybenzenethiols utilizing 7‐substituted‐1,3‐benzoxathioles is described. The structures of the prepared compounds were determined by spectroscopic methods.
A simple synthesis of some 1,10‐phenanthrolines
Authors: Butt Graeme , Topsom Ronald D.
Published: March 2009

The reaction of o‐phenylenediamine with α,β‐unsaturated ketones in the presence of hydrochloric acid smoothly affords alkyl substituted 1,10‐phenanthrolines in a one step synthesis.
Stereochemical assignments of the 7‐phenyl‐3‐oxabicyclo[4.1.0]heptanes
Authors: Corbin Dale H. , Hobbs Gregory D. , Woodyard James D.
Published: March 2009

A method for making stereochemical assignments based on nmr data for the 7‐phenyl‐3‐oxabicyclo[4.1.0]‐heptanes is described.
Preparation of some functionalized quinoxaline 1,4‐dioxides
Authors: Usta J. A. , Haddadin M. J. , Issidorides C. H. , Jarrar A. A.
Published: March 2009

The preparation of some functionalized quinoxaline 1,4‐dioxides is described from the reaction of benzofurazan oxide with 2‐acetylbutyrolactone, ethyl acetopyruvate, and acetylacetaldehyde dimethylacetal.
Synthesis and antimicrobial testing of 2‐amino‐6‐hydroxymethyl‐4‐(3H)pyrido[3,2‐d]pyrimidinone
Authors: Kelley James L. , Mclean Ed W.
Published: March 2009

Synthesis of 2‐amino‐6‐hydroxymethyl‐4‐(3H)pyrido[3,2‐d]pyrimidinone (5) from 2‐amino‐6‐methyl‐4‐(3H)‐pyrido[3,2‐d]pyrimidinone (2) was accomplished by selenium dioxide oxidation of 2 to the aldehyde 4 followed by sodium borohydride reduction. Compound 2 was available in four steps from 5‐aminouracil or in two steps from 5‐nitroisocytosine (3a). Catalytic reduction of 4 or 5 gave a mixture of 2‐amino‐6‐methyl‐5,6,7,8‐tetrahydro‐4‐(3H)pyrido[3,2‐d]pyrimidinone (6a) and the 6‐hydroxymethyl compound 6b. These compounds showed only weak inhibitory activity in the coupled reactions catalyzed by 7,8‐dihydro‐6‐hydroxymethylpterin pyrophosphokinase and 7,8‐dihydropteroate synthetase from E. Coli. No significant antibacterial activity was observed.
Reactions with diazoazoles. Part IV. . [7 + 2]‐ and [11 + 2]‐cyclocondensation reactions of diazoazoles with acyltriphenylphosphonium methylides to azolo[5,1‐c][1,2,4]triazines
Authors: Ege GÜNter , Gilbert Karlheinz
Published: March 2009

Acyltriphenylphosphoniummethylides react with diazoazoles in a [2 + 7]‐ or [2 + 11]‐cycloaddition reaction followed by elimination of triphenylphosphane oxide to yield azolo[5,1‐c][1,2,4]triazines.
Synthesis of 2‐aminochromones. Studies on the nucleophilic displacement of sulphinyl and sulphonyl groups in the 2‐position of 5,8‐dimethoxychromone
Authors: Bantick J. R. , Suschitzky J. L.
Published: March 2009

The synthesis is described of a number of N‐substituted 2‐amino‐5,8‐dimethoxychromones (1) by replacement of the sulphoxide group in 2‐ethylsulphinyl‐5,8‐dimethoxychromone (5a) with the appropriate amine. Analogous substitution of 2‐ethylsulphonyl‐5,8‐dimethoxychromone (5b) is also possible but limited by the instability of the sulphone. Replacement reactions of 5a involving oxygen, sulphur, and phosphorus nucleophiles are also described.
Synthesis of the novel isoquinoline enamide alkaloid polycarpine
Authors: Lenz George R. , Woo Chi‐Min
Published: March 2009

The synthesis of the novel enamide isoquinoline alkaloid polycarpine, (Z)‐1‐(2′‐hydroxy‐3′,4′‐dimethoxy‐benzylidene)‐3,4‐dihydro‐6,7‐dimethoxy‐2‐(1H)isoquinolinecarboxaldehyde, proceeding from commercially available 2′,3′,4′‐trimethoxyacetophenone in seven steps is described. TheO‐methyl andO‐benzyl derivatives were also obtained.
Sur un transformation inattendue de l'amino‐3 nitro‐2 benzofuranne par l'acide acétique
Authors: Demerseman Pierre , Rissé Simone , Royer RenÉ
Published: March 2009

L'acide acétique pur ou très concentré transforme lentement l'amino‐3 nitro‐2 benzofuranne en diazo‐3 dihydro‐2,3 benzofurannone‐2 dont la structure est confirmée par ses caractères spectroscopiques aussi bien que par sa réactivité chimique.
Electronic structure and molecular conformation of furan and pyrrole azomethines. An ab initio molecular orbital study
Authors: Millefiori S. , Millefiori A.
Published: March 2009

STO‐3G minimal basis set ab initio molecular orbital calculations were employed to study the electronic structure and conformational preferences in furan‐2‐N‐methylmethyleneimide (1) and pyrrole‐2‐N‐methylmethyleneimide (2). The theoretical results were examined by comparison with the parent molecular systems through a population analysis and molecular orbital interactions considerations. The OCCN‐trans and the NCCN‐cis forms were found to be the most stable structures in 1 and 2, respectively. Comparisons were made with available experimental data. The theoretical results indicate thatπ‐electron interactions and molecular orbital interactions are not significant factors in determining the conformational preferences which most likely depend on dipole‐dipole interactions.
The chemistry of carbazoles. VIII. Effect of methyl groups on the electronic spectra of carbazole
Authors: Tsunashima Yutaka , Kuroki Masatane
Published: March 2009

Electronic spectra of a number of methylcarbazoles were measured. Spectral shifts of the longest wavelength absorption bands were evaluated by the HMO‐perturbation method. The calculated shifts of 1‐substituted (group II) and 4,5‐disubstituted carbazoles (group III) did not agree with the observed values. The effect of the methyl group on the direction and magnitude of the shift is closely additive except for 4,5‐disubstituted carbazoles. The additivity principle is a useful tool for determination of methylcarbazoles.
Linear free energy ortho‐correlations in the thiophene series. Part IX . Kinetics of esterification with diazodiphenylmethane of some 3‐, 4‐, and 5‐substituted thiophene‐2‐carboxylic acids in methanol
Authors: Noto Renato , Buscemi Silvestre , Consiglio Giovanni , Spinelli Domenico
Published: March 2009

The rate constants for the esterification of some 3‐, 4‐, and 5‐substituted thiophene‐2‐carboxylic acids with diazodiphenylmethane in methanol at 25° have been measured. The reactivity of some para‐ and ortho‐substituted benzoic acids has also been determined.

Logarithmic kinetic constants for ortho‐, meta‐, and para‐like substituted thiophene‐2‐carboxylic acids furnish an excellent linear free energy relationship when plotted versus Δpka (β 0.89, r 0.989, C.L. > 99.9%, n 18, i 0.04), thus confirming the peculiar behaviour of five‐membered ring derivatives. The correlation with σH values offers an additional proof of the hyper‐ortho character of the 2,3‐relation in thiophene derivatives. para‐ and ortho‐Substituted benzoic acids show the usual behaviour of six‐membered ring derivatives.
Pyrrolo[1,2‐d]triazines‐1,2,4 III. Etude de la dioxo‐1,4 tetrahydro‐1,2,3,4 pyrrolo[1,2‐d]triazine‐1,2,4
Authors: Lancelot Jean‐Charles , Et MaxRobba Daniel Maume
Published: March 2009

La synthèse de la dioxo‐1,4 tétrahydro‐1,2,3,4 pyrrolo[1,2‐d]triazine‐1,2,4 (1) est réalisée par cyclisation du N‐carbéthoxyhydrazide de l'acide pyrrole‐carboxylique‐2 (2) et par réarrangement de la (pyrrolyl‐2)‐2 oxadiazolone‐5 (3). Les réactions de méthylation de la dione 1 effectuée avec le sulfate diméthylique et avec le diazométhane conduisent à des mélanges de dérivés O‐méthylés et N‐méthylés qui sont séparés par chromatographic en phase gazeuse et dont la structure est établie à l'aide des spectres ir et de rmn 1H.
Studies on the synthesis of heterocyclic compounds. Part VI. The action of methyl salicylate on some 5‐aminopyrazoles
Authors: Daidone Giuseppe , Plescia Salvatore
Published: March 2009

Some 1‐phenyl‐3‐R‐5‐aminopyrazoles reacted with methyl salicylate to give N‐(1‐phenyl‐3‐R‐pyrazol‐5‐yl)‐2‐methoxybenzamides (3a,b,c), 1‐phenyl‐2‐methyl‐3‐R‐salicyloilimino‐3‐pyrazolines (4a,b,c) together with 1‐phenyl‐3‐R‐5‐methylamino pyrazoles (5a,b,c). The structures of the new compounds 3 and 4 were determined on the basis of analytical and spectroscopic data as well as on the acid hydrolysis products.
Transformation thermique des β‐(méthyl‐2 furyl)‐3 acryloylazides: Nouveau mode de formation de certaines pyrimidines
Authors: Bisagni Emile , Lhoste Jean‐Marc , Hung Nguyen Chi
Published: March 2009

Par chauffage à 240° dans le diphényléther, les β‐(méthyl‐2 furyl)‐3 acryloylazides ne conduisent paus aux furo[3,4‐c]pyridones attendues suivant la réaction d'Eloy et Deryckere mais à des pyrimidines‐diones‐2,4 résultant de la dimérisation des vinylisocyanates formés intermédiairement.
Synthesis of 3‐substituted 7‐(3,3‐dimethyl‐1‐triazeno)‐10‐methylphenothiazines as potential antitumor agents
Authors: Lin Ai Jeng , Kasina Sudhaka
Published: March 2009

A series of 3‐substituted (chloro, bromo, fluoro or methyl) 7‐(3,3‐dimethyl‐1‐triazeno)‐10‐methylphenothiazines were synthesized as potential antitumor agents. Treatment of p‐substituted anilines with ammonium thiocyanate in the presence of bromine gave 6‐substituted 2‐aminobenzthiazoles which, after methylation with methyl iodide were hydrolyzed in 50% potassium hydroxide to give 5‐substituted 2‐methylaminothiophenols in moderate yield. Condensation of methylaminothiophenols with 3,4‐dichloronitrobenzene in ethanol under an atomsphere of nitrogen gave adducts which were cyclized in dimethylformamide under the catalysis of copper and cuprous iodide to give 3‐substituted 7‐nitro‐10‐methylphenothiazines. The nitro group was reduced to the amino function with stannous chloride. Diazotization of the amines followed by coupling with dimethylamine gave the corresponding triazenes.
Selenium heterocycles. XXXII . Synthesis of [1]benzoxepino[3,4‐d]‐thiazole, [1]benzothiepino[3,4‐d]thiazole, [1]benzoxepino[3,4‐d]selenazole, and [1]benzothiepino[3,4‐d]selenazole. four novel heterocycles
Authors: Shafiee A. , Kiaeay G. , Vosooghi M.
Published: March 2009

Starting from the readily available ethyl 2‐phenyl‐4‐methyl‐thiazole‐5‐carboxylate (III), 2‐phenyl‐4‐chloromethyl‐thiazole (VIII) and 2‐aryl‐4‐chloromethylselenazole (XIV), 2‐phenyl‐4,10‐dihydro‐10‐oxo‐[1]benzoxepino[3,4‐d]thiazole (Ia), 2‐phenyl‐4,10‐dihydro‐10‐oxo[1]benzothiepino[3,4‐d]thiazole (Ib), 2‐aryl‐4,10‐dihydro‐10‐oxo[1]benzoxepino[3,4‐d]selenazoles (IIa‐IIe) and 2‐aryl‐4,10‐dihydro‐10‐oxo[1]benzothiepino[3,4‐d]selenazoles (IIf‐IIj) were prepared.
Substituent effects in heterocyclic systems by carbon‐13 nuclear magnetic resonance. Isoxazoles
Authors: Chrisope Douglas R. , Keel Rebecca A. , Baumstark Alfons L. , Boykin David W.
Published: March 2009

The carbon‐13 nmr spectra of a series of 3‐aryl‐5‐phenylisoxazoles (I) and 3‐phenyl‐5‐arylisoxazoles (II) have been recorded and the signals assigned. Carbon‐13 data for series I show little effect of substituent on the chemical shift of the isoxazole ring carbons. However, a plot of the carbon‐13 chemical shift of carbon‐5 in the isoxazole system I versus the chemical shift of carbon‐3 in the 3‐(4′‐aryl)‐1‐phenylpropenones gives a straight line (r = .989) with a slope of 0.35. In series II, the chemical shifts of both carbon‐4 and ‐5 are relatively sensitive to substituent effects. Fair correlations between Hammett sigma values and the chemical shifts of these two carbons are found; dual substituent parameter treatment improves the correlations. The results obtained from correlations with carbon‐4 in series II are similar to those obtained from β‐carbons of a number of styrene systems. The data show that carbon‐4 in series II is approximately 20% less sensitive to substituent effects than the previously reported data for carbon‐3 of 2‐arylfurans. Transmission of substituent effects in the isoxazole system compare well with those of the benzothiazole system.
Reactions of benzothiohydrazide as a bidentate nucleophile
Authors: Elliott Arthur J.
Published: March 2009

Benzothiohydrazide acts as a 1,4‐bidentate nucleophile under basic conditions, and condenses with suitably substituted pyridines, pyrimidines and quinoxalines to yield ring‐fused‐1,3,4‐thiadiazines un‐substituted on the 4‐nitrogen position.
Alkylation et acylation d'acridanones‐9
Authors: Blanchard Christiane , Montginoul Claude , Torreilles Eliane , Giral Louis
Published: March 2009

Nous décrivons les N‐alkylations et les N‐acylations d'acridanones‐9 substituées en position 2 ou 3 par des groupements nitro et méthoxy. Les caractéristiques physiques des nouveaux composés ainsi obtenus sont données.
Functional derivatives of thiophene. I. Synthesis and 1H‐NMR spectra in the 2‐aminothiophene series
Authors: Galvez C. , Garcia F.
Published: March 2009

The preparation of 2‐amino‐5‐nitrothiophene, 2‐formamido‐5‐nitrothiophene, 2‐acetamido‐5‐nitrothiophene and 2‐t‐butyloxycarbonylamino‐5‐nitrothiophene are described. Abnormal values of the coupling constants J3.4 had been observed in the 1H‐nmr spectra of compounds obtained.
Facile deacylation of N‐acyl‐2,3‐dihydrobenzo‐1,4‐thiazine 1‐oxide and 1,1 dioxide
Authors: Florio Saverio , Leng John L. , Stirling Charles J. M.
Published: March 2009

The title amides react easily with methanolic sodium methoxide at room temperature affording 2,3‐dihydrobenzo‐1,4‐thiazine 1‐oxide and 1,1‐dioxide and methylacetate. An unusual mechanism of deacylation is proposed.
Synthesis of a non‐flexible analog of chlorpromazine
Authors: Elliott Arthur J. , Guzik Henry
Published: March 2009

9‐Chloro‐2‐dimethylaminomethyl‐1,2‐dihydropyrrolo[3,2,1‐kl]phenothiazine (3b), a conformationally restricted analog of chlorpromazine, has been synthesised and has been found to be devoid of neuroleptic activity.
Some 2‐(dialkylamino) substituted chromenylium salts
Authors: Mazzei M. , Ermili A. , Sottofattori E. , Roma G.
Published: March 2009

The reaction of 2‐(dialkylamino)‐7‐methoxychromones with malononitrile in the presence of acetic anhydride afforded [2‐(dialkylamino)‐7‐methoxy‐4H‐chromen‐4‐ylidene]malononitriles. When these compounds were refluxed with concentrated hydrochloric (or hydroiodic) acid, 2‐(dialkylamino)‐7‐methoxy(or hydroxy)‐4‐methylchromenylium salts were obtained. The use of concentrated sulfuric acid or polyphosphoric acid in the hydrolysis was also investigated. The preparation of ethyl [2‐(dialkylamino)‐7‐methoxy‐4H‐chromen‐4‐ylidene]cyanoacetates and their behavior when treated with acids are also described, as well as the synthesis of some 3‐(dialkylamino)‐1‐methylnaphtho[2,1‐b]pyrylium salts.
The reaction of nitriles with mercaptoacetic acid. A new synthesis of thiazole derivatives
Authors: Elnagdi Mohamed Hilmy , Khalifa Mohamed Ali Elsayed , Ibraheim Mohamed Kamal Ahmed , Elmoghayar Mohamed Riffat Hamza
Published: March 2009

The reaction of mercaptoacetic acid with nitriles was investigated. Whereas 4‐hydroxythiazole derivative could be obtained from the reaction of benzoylacetonitrile and of ethyl cyanoacetate with mercaptoacetic acid, a bithiazole derivative was obtained on treatment of benzonitrile with the same reagent. The behaviour of the synthesised thiazole derivatives towards aromatic aldehydes and hydrazines is reported.
Mesoionic six‐membered heterocycles. XIV. Crystal structure of a pyrimidine belaine
Authors: Kratky Christof , Kappe Thomas
Published: March 2009

The crystal structure of a mesoionic pyrimidine was determined by means of an X‐ray structure analysis. The structure is discussed in terms of Dähne's concept as consisting of two coupled polymethines.