bluuebunny/crossref_metadata_2025 huggingface dataset:
The synthesis and reactions of certain 3‐substituted‐2,1‐benzisothiazoles
Authors: Albert Anthony H. , O'Brien Darrrell E. , Robins Roland K.
Published: April 2009

A new and general synthesis of 2,l‐benzisothiazolin‐3‐ones (2) is described from the corresponding isatoic anhydride (3) and potassium hydrogen sulfide which gives the thioanthranilic acid (4) which is readily oxadized and ring closed to 2 with hydrogen peroxide. Phosphorus oxy‐chloride converted 3‐hydroxy‐2,1‐benzisothiazole to 3‐chloro‐2,1‐benzisothiazole which gave a number of different 3‐substiluted 2,1‐benzisothiazolesby nucleophilic substitution of the 3‐chloro group. Rleetrophilie substitution of 1‐methyl‐2,1 ‐benzisothiazoIin‐3‐one (2i) proceeded readily to give the corresponding 5‐bromo‐, 5‐nitro‐, and 5‐chlorosulfonyl‐1‐methyl‐2,1‐benzisothiazolin‐3‐one. This appears to be a good synthetic route to such 2,1‐benzisothiazole derivatives.
Carbon‐13 nuclear magnetic resonance spectra of isoquinoline alkaloids
Authors: Singh S. P. , Parmar S. S. , Stenberg V. I. , Farnurn S. A.
Published: April 2009

The 13C nmr ehemieal shifts of 1,2,3,4‐tetrahydroisoquinoline, salsolidine and laudanosine are reported. The various carbon resonances have been assigned on the basis of chemical shift theory, intensity of the signals, multiplicities generated in SFORD spectra and the comparison with model compounds.
Quinazolincs and 1,4‐benzodiazepines. LXXXVI. The synthesis of imidazothienodiazepines and imidazopyrazolodiazepines
Authors: Fryer R. Ian , Earley James V. , Walser Armin
Published: April 2009

The thieno[3,2‐e][1,4]diazepin‐2‐one (1a), the thieno[2,3‐e] [ 1,4] diazepin‐2‐one (1b), the pyrazolo[3,4‐e][1,4]diazepin‐2‐one (1c) and a chloro analog of 1b, compound 1d, were each converted to derivatives of the novel tricyclic ring systems 4H‐imidazo[1,5‐a]thieno[2,3‐f] [1,4]‐diazepine, 4Himidazo[1,5a]thieno[2,3f][1,4]diazepine and 4H‐imidazo[ 1,5‐a]pyrazolo[4,3‐f]‐[1,4]diazepine. Depending on the substituents desired on the imidazo ring, two different synthetic pathways were employed.
The stereochemistry of 2‐oxoindolin‐3‐ylidene derivatives
Authors: Long D. R. , Richards C. G. , Ross M. S. F.
Published: April 2009

The stereochemistry of a number of functionally‐substituted 2‐oxoindolin‐3‐ylidene derivatives has been established by a study of pmr and ir spectroscopy. These compounds have been shown to exist as one isomer with the exception of the substituted acetonitriles.
Sur la ribosylation de divers mercapto‐2 benzoazoles
Authors: Cosselin G. , Loukil H. F. , Mathieu A. , Mesli A. , Imbach J‐L.
Published: April 2009

Nous avons effectué en série mercapto‐2 benzoazole une étude comparative de la réaction de ribosylation de ces bases en utilisant trois techniques parmi les plus employées: la fusion acido‐catalysée, la condensation des dérivés silylés des aglycones avec un acétoxy‐1 et avec un halogéno‐1 sucre.

Les N‐β‐nucléosides correspondants ont, dans tous les cas, été isolés et identifiés sans ambiguité. On peut noter toutefois la réactivité particuliére observée en série benzimidazole puisque nous avons pu mettre en évidence dans certaines de ces condensations la formation du N,N ‐diriboside et d'un anhydro‐2,2′ nucléoside.
Synthesis of 4‐imidazolin‐2‐ones via the birch reduction of hydantoins
Authors: Divanfard Hosein R. , Ibrahim Yehia A. , Joullié Madeleine M.
Published: April 2009

The reduction of 5‐(5‐methyl‐2‐furyl)hydantoin to 4‐(5‐methyl‐2‐luryl)‐4‐imidazolin‐2‐one is described.
8‐Methyl‐5,6,7,8‐tetrahydroeoumarin
Authors: Feutrill G. I. , Mirrington R. N.
Published: April 2009

Acid‐catalysed cyclodehydration of β‐(2‐keto‐3‐methylcyclohex‐3‐enyl)propionic acid proceeded efficiently to 8‐methyl‐5,6,7,8‐tetrahydrocoumarin.
A general method for the preparation of N‐monosubstituted‐3‐isothiazolamines
Authors: Rokach J. , Hamel P.
Published: April 2009

We describe here a novel and general high yield method for the synthesis of 3‐alkyl and arylaminoisothiazoles, a previously unknown group of isothiazoles, by the reaction of ammonia with 3‐halo‐2‐alkylisothiazolium salts. The mechanism of the reaction probably involves a ring opening followed by a recyclization to the title compounds.
Die bildung von thiirenen
Authors: Timm Uwe , BÜhl Hanspeter , Meier Herbert
Published: April 2009

Photochemical nitrogen elimination of 1,2,3‐thiadiazoles leads to primary fragments (1, X = S), which are able to cyclize to thiirenes (2, X = S). An exception is found for bicyclic systems like 4. These results, gained by isotope labelling experiments are related to the oxirene formation of α‐oxocarbenes.
Constituents of cannabis sativa L. An improved method for the synthesis of dl‐cannabichromene
Authors: Eisohly Mahmoud A. , Boeren Edward G. , Turner Carlton E.
Published: April 2009

A new procedure was developed for the synthesis of cannabichromene (III) which involves reflux of equimolar amounts of olivetol (I), citral (II) and t‐butylamine in toluene for 9 hours. The purification of III was best achieved by sodium borohydride reduction of unreacted II followed by column chromatography on 1% sodium hydroxide impregnated silica gel 60‐PF. The yield of III (62.0%) was much higher than that reported in the literature.
Novel chlorination of 4′,5,7‐trihydroxyflavanone with cupric chloride‐oxygen
Authors: Takizawa Yasuomi , Mitsuhashi Tatsuo
Published: April 2009

Novel chlorination of 4,5,7‐trihydroxyflavanone with copper(II) chloride and oxygen is described. 6,8‐Dichloro‐4′,5,7‐trihydroxyflavanone (2) and 6,8‐dichloro‐4,4′,5,7‐tetraacetoxyflav‐3‐ene (3) were newly synthesized.
A synthesis of pyrrolo[ 3,2,1‐kl] phenothiazine and derivatives
Authors: Hollins Richard A. , Pinto Angelo C.
Published: April 2009

A synthesis of pyrrolo[3,2,1‐kl]phenothiazine (1) is described. Electrophilic substitution of 1 leads to functionalization at the 2 position.
Nouvolle synthcse de la dihydro‐5,6 methoxy‐6 2H‐pyrannone‐5
Authors: Saroli Alfred , Descours Denis , Anker Daniel , Pacheco Henri
Published: April 2009

L'obtention de la cétone α,β éthylénique 5 à partir de la cétone saturée 1 est réalisée en quatre etapes avec un rendement de 35%. L'intermédiaire de réaction est Pacetal brome obtenu sous forme d'un mélange des deux isomères 6 et 7; leur stéréochimie et leur conformation sont mises en évidence par étude rmn à 250 MHz. Lors de leur débromhydratation, une isomérisation de I'acetal α,β éthylénique 4, relativement aisée, peut ětre réalisee par migration de la double liaison pour conduire à 1′acétal β,γ éthylénique 10.
Meso heterocyclic analogues of 9,10‐dihydroanthraeene. XIII. On the structure of the products of diacetylalion of phenoxathiin: A correction
Authors: Coïc J.‐P. , Saint‐Ruf G.
Published: April 2009

The diacetylation of phenoxathiin under the typical conditions for Friedel‐Crafts reaction results in a mixture consisting of 2,7‐diacetylphcnoxathiin (3) and 2,8‐diacetylphenoxathiin (9). The compound hitherto descrihed in the literature as 9 proved to be in reality the mixture. For the first time, the compound 3 was isolated, purified and had its structure established. 3,4′‐Diethyldiphenyloxide as well as 2,7‐ and 2,8‐diethylphenoxathiins and their sulphones and sul‐phoxides have been synthesized.
New syntheses of pyrimido[4,5‐c]pyridazines related to fervenulin
Authors: Senga Keitaro , Sato Junko , Kanamori Yukako , Ichiba Misuzu , Nishigaki Sadao , Noguchi Mitsukò , Yoneda Fumio
Published: April 2009

Pyrimido[4,5‐c]pyridazines related to an antibiotic fervenulin were prepared by two routes: one involving the reaction of 6‐hydrazino‐1,3‐dimethyl(or 3‐methyl)uracil with phenacyl bromides, and the other involving the reaction of 6‐benzylidenehydrazino‐1,3‐dimethyluracils with dimethyl‐formamide dimethylacetal.
Studies on 1H‐ and 2H‐N‐alkylpyrazolo[3,4‐d]pyridazin‐4(5H)ones
Authors: Gelin Suzanne , Hartmann Daniel
Published: April 2009

A series of two N‐substituted‐3(5)acyl4‐ethoxycarbonyl‐5(3)substituted isomeric pyrazoles underwent ring closure with hydrazine and methylhydrazine to give the new anticipated N(1)‐or N(2)alkyl‐3,7‐disubstituted pyrazolopyridazin‐4(5H)ones. The purpose of this study was to determine distinguishing criteria between the two isomers. From the comparative 1 H‐ and 1 3C‐nmr spectra, sufficiently significant differences were observed. Uv and ir spectra showed no significant differences.
1H Nmr study of the preferred conformations in N‐alkylgranatanine‐3‐spiro‐5′‐hydantoins
Authors: Trigo G. G. , Avendaño C. , Ballesteros P. , Gonzalez A.
Published: April 2009

The conformations of a new series of compounds of the general structure N‐alkylgranatanine‐3‐spiro‐5′‐hydantoin, synthesized in our laboratory from the corresponding 9‐alkyl‐9‐azabieyclo‐[3.3.1 ]nonan‐3‐ones, were studied by 1 H nmr spectroscopy at different pH values in some instances. We have assigned boat conformations for the spiropiperidines.
Syntheses of 5‐amino‐3‐(β‐d‐ribofuranosyl)imidazo [4,5‐b] pyridin‐7‐one (1‐deazaguanosine) and related nucleosides
Authors: Cline Barry L. , Panzica Raymond P. , Townsend Leroy B.
Published: April 2009

The synthesis of 5‐amino‐3‐(β‐D‐ribofuranosyl)imidazo[4,5‐b ]pyridin‐7‐one (1‐deazaguano‐sine) has been accomplished by three different methods. The 6‐thioguanosine analog 5‐amino‐3‐(β‐D‐ribofuranosyl)imidazo [4,5‐b ]pyridin‐7‐thione (1‐deaza‐6‐thioguanosine) has been prepared in situ by a reduction of the corresponding disulfide. The synthesis of various nucleoside precursors of the above compounds by several condensation procedures are described. The procedures used to unequivocally determine the site of ribosylation and anomeric configuration are also discussed.
Etude de la réaction de l'acé'tylacé'tate d'éthyle avec les diamino‐1,5 imidazoles
Authors: Bernardini A. , Viallefont Ph. , Zniber R.
Published: April 2009

L'action d'un β‐cetoéster tel Fàcétylacétate d'éthyle sur les diamino‐1,5 imidazoles conduit a deux types de réactions concurrentes et permet de synthétiser des imidazo[1,5‐b]triazépinones et des imidazo[4,5‐b]pyridinones. Les produits obtenus ont une structure lactamique qui correspond à l'action de la fonction ester sur le groupe amino non hydrazinique du diamino‐imidazole. Un nouveau type de transposition des imidazotriazépinones en imidazopyridinones a été mis en évidence, il résulte de la réactivité particulière de la double liaison C=N du cycle à sept éléments.
Heterocyclic compounds. X. A new synthesis of thiadiazasteroids
Authors: Manhas M. S. , Sugiura M. , Chawla H. P. S.
Published: April 2009

The reaction of ν‐ketoacids or ν‐aldehydo acids with o‐amino amides results in the formation of 4‐quinazolones. Using this reaction a number of polyheterosteroid analogs were synthesized. Thus, when 2‐amino‐3‐carboxamido‐4,5,6,7‐tetrahydrobenzothiophene (9) was refluxed with levulinic acid (10) in a high boiling solvent, thiadiazasteroid analog (11) was obtained in 78% yield. It was found that this facile one‐step reaction could be used to synthesize a variety of tetra and pentacyclic compounds. Nmr spectroscopy was used to assign stereochemistry to the 17‐methyl “steroids” (31) and (32).
[1]Benzofuro[2,3‐d]pyridazine III. Etude de la dichloro‐1,4 benzofuropyridazine
Authors: de Sevricourt Michel Cugnon , Robba Max
Published: April 2009

Les réactions de substitution régiosélectives de la dichloro‐1,4 benzofuropyridazine concernent la position 1. La chloro‐4 hydrazino‐1 benzofuropyridazine se prěte a des cyclisations menant à des chloro‐6 s‐triazolo[1,2‐b]benzofuropyridazines et à la chloro‐6 tétrazolo[1,5‐b]benzo‐furopyridazine dont les substitutions nucléophiles sont étudiées.
Cinnoline chemistry XIII. 4‐aziridinocinnolines
Authors: Yamazaki Takao , Draper Randall E. , Castle Raymond N.
Published: April 2009

Nine substituted 4‐aziridinoeinnolines have been prepared and subjected to anticancer screening. J. Heterocyclic Chem., 15, 1039 (1978)
Benzomorphan related compounds. VII. Synthesis of benzothienomorphans
Authors: Alvarez M. , Bosch J. , Feliz M.
Published: April 2009

The synthesis of some benzo [b] thieno [2,3‐f] ‐ and [3,2‐f] morphans by the Grewe method is described. Spectroscopic data of these compounds and of the intermediate isomeric tetrahydropyridines are included. A side‐product isolated from the aluminum bromide cyclization of the 2‐(2‐benzothienylmethyl)tetrahydropyridine IVd is reported and a mechanism for its formation is proposed.
Synthesis of pyridyloxadiazoles 2. 2‐(Oxadiazolyl)pyridines and 2,6‐bis(oxadiazolyl)pyridines as analogues of pyridinolcarbamate
Authors: Suárez Cecilia , Diparsia Maria T. , Márquez Victor E.
Published: April 2009

Four 2‐(oxadiazolyl)pyridines and three 2,6‐bis(oxadiazolyl)pyridines, considered as potential analogues of pyridinolcarbamate (PC), were prepared and screened for antithrombotic activity against ADP‐ and collagen‐induced platelet aggregation. All the compounds showed activity below the critical response expected for this category of drugs.
A new synthesis of 3,6‐dialkyl, diaryl and diheterocyclic‐1,2‐dihydro‐l, 2,4,5‐tetrazines
Authors: Cohen Victor Israel
Published: April 2009

Some 3,6‐dialkyl, diaryl and diheterocyclic‐1,2‐dihydro‐1,2,4,5‐tetrazines have been synthesized from the action of hydrazine on aliphatic selenonesters, and aromatic and heterocyclic selenoamides.
Preparation of isatoates from isatoic anhydride
Authors: Heyman Duane A.
Published: April 2009

A wide variety of alkyl isatoates can be prepared in good yield from the high temperature reaction of isatoic anhydride with alcohols. Isatoates were found to undergo an apparent high temperature rearrangement reaction. Proposed reaction schemes are presented for the formation of isatoates and the subsequent rearrangement reaction.
3‐Diazopyrazolo[3,4‐b] pyridine, a versatile synthon for new heterocyclic systems
Authors: Kočevar M. , Stanovnik B. , Tišler M.
Published: April 2009

3‐Diazopyrazolo[3,4‐b] pyridine was synthesized and its transformations were investigated. With reactive methylene compounds the corresponding hydrazones are formed and they can be cyclized into condensed 1,2,4‐triazine derivatives. With amines of thiols the diazo compound forms triazenes or diazosulfides. From hydrazines tetrazenes are formed first and they give upon fragmentation a mixture of N‐N or C‐N bond fission products. The diazo compound undergoes cycloaddition, reacting as a 1,2‐dipole. 3‐Azidopyrazolo [3,4‐b] pyridine was prepared and converted into the tetrazolo isomer, whereas the 3‐amino compound was used for the synthesis of some pyridopyrazolopyrimidines.
Synthesis of 3(2‐ and 4‐Pyridinyl)‐1,3,4‐oxadiazol‐2(3H)ones
Authors: Giacobbe Thomas J.
Published: April 2009

The synthetic objective of preparing halo‐ and halo‐ plus alkoxy‐substituted pyridyloxadiazolones was achieved by allowing an alkali metal salt of an oxadiazolone to displace a leaving group on a halo‐ or halo‐ plus alkoxy‐substituted pyridine, respectively. Other routes failed to give the desired compounds, and they are briefly discussed.
Synthesis of the macrocyclic polythia ether, [7.7](2,6)dithia(2,5)thiophenophane
Authors: Bhattacharjya Anup , Hortmann Alfred G.
Published: April 2009

The macrocyclic polythia ether [7.7](2,6)dithia(2,5)thiophenophane 2 has been prepared by condensation of the dilithio salt of propane‐1,3‐dithiol with 2,5‐bis (chloromethyl)lhiophene.
Fluoroazoles. II. Synthesis and 1H and 19F Nmr spectra of 2‐, 4‐, and 5‐Fluoro‐1‐methylimidazole
Authors: Fabra F. , Gálvez C. , González A. , Viladoms P. , Vilarrasa J.
Published: April 2009

The three possible ring‐monofluorinated N‐methylimidazoles have been prepared by photochemical irradiation of the corresponding diazonium tetrafluoroborates. 5‐Fluoro‐1‐methyl‐imidazole was also obtained by methylation of 1‐acetyl‐4‐fluoroimidazole. The 1H and 19F nmr spectra of these N‐methylated fluoroazoles are compared, and the predominance of one tautomeric form in 4(5)‐fluoroimidazole is discussed.
Novel syntheses of hydantoin derivativesK
Authors: Iwata K. , Tiara S.
Published: April 2009

N‐Substituted hydantoin derivatives have been synthesized by the condensation of an α‐amino acid derivative, a primary amine and diphenyl carbonate. The method has been applied to the synthesis of hydantoin derivatives with two hydroxyl and/or carboxyl groups.
Syntheses with α‐heterosubstituted phosphonate carbanions. VIII. An unexpected entry into quinolines
Authors: Zimmer Hans , Nene Dilip M.
Published: April 2009

The carbanions derived of certain diphenyl‐1‐(4‐nitroanilino)‐1‐(substituted‐aryl)methanephosphonates reacted with phenylpropargyl aldehyde, giving not the expected yne‐enamines, but rather 2‐phenyl‐4‐benzyIquinolines.
Oxidation of quinazoline and quinoxaline by xanthine oxidase and aldehyde oxidase
Authors: Mccormack John J. , Allen Barbara A. , Hodnett C. Nicholas
Published: April 2009

Quinazoline is oxidized by xanthine oxidase initially (and rapidly) to 4‐hydroxyquinazoline which subsequently is oxidized more slowly to 2,4‐dihydroxyquinazoline. Both oxidative reactions are inhibited strongly by allopurinol. Quinazoline is oxidized by aldehyde oxidase to 4‐hydroxyquinazoline but within a short time (3–5 minutes) the reaction ceases; the proposal that cessation of reaction is due to product inhibition is rendered untenable by our observation that 4‐hydroxyquinazoline is rapidly oxidized by aldehyde oxidase to 2,4‐dihydroxyquinazoline. Preincubation of aldehyde oxidase with quinazoline results in complete inhibition of the ability of the enzyme to oxidize 4‐hydroxyquinazoline and the standard substrateN‐methylnicotinamide. It appears therefore that quinazoline is able to react with aldehyde oxidase and inactivate it. Quinoxaline and 2‐hydroxyquinoxaline are not oxidized by xanthine oxidase but are converted by aldehyde oxidase to 2,3‐dihydroxyquinoxaline; all oxidations mediated by aldehyde oxidase are inhibited completely by menadione.
Synthesis and structure of dihydro‐1,2,4‐triazin‐6(1H) ones
Authors: Camparini Alfredo , Celli Angela Maria , Ponticelli Fabio , Tedeschi Piero
Published: April 2009

Reactions of the iminoesters 3a‐c with hydrazine or 1,2‐dimethylhydrazine gave 4,5‐dihydro‐4a‐c or 2,5‐dihydro‐1,2,4‐triazin‐6(1H) ones 7a‐c, respectively. When methylhydrazine was employed, 1‐methyl‐4, 5‐dihydro‐ 5a‐c and 2‐methyl‐2,5‐dihydro‐1,2,4‐triazin‐6(1H) ones 6a‐c were obtained. Compounds 6a‐c exist as zwitterions in the solid state and in polar aprotic solvents.
Tetracyclic phenothiazines. III. . Intermolecular hydride transfer in acid induced disproportionation of 1,2‐dihydro‐3‐hydroxy‐3H‐pyrido[3,2,1‐kl] phenothiazines
Authors: Martin A. R. , Kim S. H. , Peng G. W. , Siegel G. V. , Yale T. J.
Published: April 2009

1,2‐Dihydro‐3‐hydroxy‐3H‐pyrido[3,2,1‐kl]phenothiazines and 1H‐pyrido[3,2,1‐kl]phenothiazines undergo acid catalyzed disproportionation with intermolecular hydride transfer to form pyrido[3,2,1‐kl]phenothiazinium salts and 1,2‐dihydro‐3H‐pyrido[3,2,1‐kl]phenothiazines. Sodium borohydride reduction of 3‐alkyl‐ or 3‐arylpyrido[3,2,1‐kl]phenothiazinium salts gives 3‐alkyl‐ or 3‐aryl‐1H‐pyrido[3,2,1‐kl]phenothiazines. In the presence of a proton source, borohydride reduction of pyrido[3,2,1‐kl]phenothiazinium fluoroborate or 3‐chloropyrido‐[3,2,1‐kl]phenothiazinium perchlorate gives 1,2‐dihydro‐3H‐pyrido[3,2,1‐kl]phenothiazine, while 1H‐pyrido[3,2,1‐kl]phenothiazine is formed in aprotic solvents with pyridine present.
Studies on the synthesis of heterocyclic compounds. Part II. Action of phosphorus oxychloride on N‐Methyl‐N‐1‐phenyl‐3‐methylpyrazol‐5‐yl)‐2‐acetamidobenzamide
Authors: Plescia S. , Daidone G. , Sprio V. , Aiello E. , Dattolo G. , Cirrincione G.
Published: April 2009

During attempts to prepare the tricyclic ring system of type III by cyclization of N‐methyl‐N‐(1‐phenyl‐3‐methylpyrazol‐5‐yl)‐2‐acetamido benzamide (Ib) under Bischler‐Napieralski reaction conditions, the formation of the macro‐heterocycle IV was observed, whose structure was determined on the basis of analytical and spectroscopic data as well as on some transformation products.
Synthesis of 4‐hydroxy‐ and 4‐mercaptoquinazoline derivatives
Authors: Cohen Victor Israel
Published: April 2009

The reaction of selenoesters with o‐aminobenzamide and o‐aminothiobenzamide derivatives led to the formation of 4‐hydroxy‐ and 4‐mercaptoquinazolines. Their structures were elucidated by means of elemental analyses and spectropic data (nmr and ms).
Tetracyclic phenothiazines IV . Synthesis of 1,2,3,4‐Tetrahydro‐azepino [3,2,1‐kl] phenothiazin ‐4‐one
Authors: Kim Sun H. , Martin Arnold R.
Published: April 2009

The synthesis of 1,2,3,4‐tetrahydroazepine[3,2,1‐kl]phenothiazin‐4‐one was accomplished by cyclization of phenothiazine‐10‐butanoic acid using phosphorus pentoxide and absolute ethanol. The title compound represents the first reported example of the azepino[3,2,1‐kl]phenothiazine ring system. A vastly improved malonic ester‐type synthesis of the precursor acid has also been developed.
Synthesis of pyridine analogs of cumyl chloride‐2‐chloro‐2‐(pyridyl) propanes
Authors: Feuer Henry , Doty James K.
Published: April 2009

Chlorination of the isomeric isopropylpyridines with t‐butyl hypochlorite affords the tertiary α‐chloroalkylpyridines in good yield.
The reaction of 2,4‐diamino‐6‐piperidinopyrimidine 3‐oxide with acid anhydrides
Authors: Mccall John M. , Tenbrink Ruth E. , Royer Max E. , Ko Howard
Published: April 2009

2,4‐Diamino‐6‐piperidinopyrimidine 3‐oxide reacts preferentially with acid anhydrides at the 4‐amino group. The structures of amide products are readily assigned by the position of the 5‐H.
Synthesis and reactivity with organometallic reagents of benzimidazole N‐oxides
Authors: Berti C. , Colonna M. , Greet L. , Marchetti L.
Published: April 2009

An easy synthesis of benzimidazole N‐oxides, and their reactivity with organometallic reagents to give stable nitroxide radicals, are described. 1‐Hydroxy‐2‐phenylbenzimidazole does not react in spite of its tautomeric equilibrium with the N‐oxide structure.
The contrasting behavior of cyclic and acyclic 2‐amidomethyleneresorcinols towards cyclization with acetaldehyde
Authors: Zaugg H. E. , Arendsen D. L. , Egan R. S.
Published: April 2009

The two cyclic amidomethylene resorcinols, 3a and 3b, readily undergo cyclization with acetaldehyde to the azacannabinoids 4 and 6, respectively. However, the acyclic amidomethylene resorcinol 10, under the same conditions, gives the benzodioxan 11. This contrasting behavior is rationalized in terms of conformational differences between 3a,b and 10.
Nitro group participation in the formation of heterocycles
Authors: Sunder Shyam , Peet Norton P.
Published: April 2009

Benzoyl bromide (2‐nitrophenyl) hydrazone (2) was treated with sodium ethoxide and ethyl cyanoacetate and two unexpected products were obtained. These products were ultimately shown to be 6‐bromo‐3‐phenyl‐1,2,4‐benzotriazine (32) and 5‐bromo‐2‐phenylbenzoxazole (38), by comparison with authentic samples which were synthesized. A mechanism is presented for the formation of these two heterocyclic systems (32 and 38) from 2.
The kinetics of the reaction of some chloroisoxazolo[4.5‐c] and [5,4‐b] pyridines with methoxide ion
Authors: Adembri Giorgio , Ponticelli Alfredo Camparini Fabio , Tedeschi Piero
Published: April 2009

Arrhenius parameters were measured for the methoxy‐lechlorination reactions of some chloroderivatives of isoxazolo[4,5‐c]‐ and [5,4‐b]pyridine. A comparison of these results with the kinetic data for the corresponding chloropyridines shows that fusion of the isoxazole ring with the pyridine ring strongly increases the reactivity of the 4‐ and 6‐positions toward nucleophilic substitution.
Chemistry of the phenoxathiins VIII. Synthesis of 7‐chlorobenzo[1″.2″:5,6:3″,4″:5′,6′] bis[1,4] oxathiino[3,2‐b:3′.2′‐b′]dipyridine
Authors: Martin Gary E. , Turley James C. , Schram Karl H.
Published: April 2009

As a continuation of recent study on the synthesis of a bis[1,4]oxathiinodipyridine ring system, we would now like to report the preparation of 7‐chlorobenzo[1″,2″:5,6:3″,4″:5′,6′]‐bis[1,4]oxathiino[3,2‐b: 3′,2′‐b]dipyridine. Although a potentially complex reaction with several products possible, the title compound was formed exclusively, suggesting considerable mechanistic selectivity. The characterization of the product by FT‐1H‐nmr as well as its mass spectral fragmentation pathways are also reported.
Reactions with cyclic amidines II. The behaviour of cyclic amidines toward ethoxycarbonyl and aroyl isothiocyanates
Authors: Elnagdi Mohamed Hilmy , Fahmy Sherif Mahmoud , Elmoghayar Mohamed Rifaat Hamza , Kandeel Ezzat Mohamed
Published: April 2009

The behaviour of the aminopyrazole derivatives 1a‐c, 2‐amino‐4‐phenylthiazole (2) and 2‐amino‐5‐phenyl‐1,3,4‐thiadiazole (3) toward the action of ethoxycarbonyl and benzoyl iso‐thiocyanate is reported. The data clearly demonstrates the dependence of the nature of the products obtained from the reaction of isothiocyanates with cyclic amidines on the nature of the substituents on the heterocyclic ring.
Heterocycles from substituted amides. VI. A new carbostyril synthesis from alpha‐substituted acetamides and the vilsmeier reagent
Authors: Chupp John P. , Metz Suzanne
Published: April 2009

Reaction of tertiary α‐substituted acetanilides with Vilsmeier reagent has been found to give 1,3‐disubstituted‐carbostyrils, 1. α‐Chloro‐N‐(1‐cyclohexen‐1‐yl) acetamides are similarly converted to tetrahydro carbostyrils 2 and 3. The method appears useful for the preparation of a variety of 1,3‐substituted 2(1H) quinolinones. The scope and mechanism of the reaction has been investigated, with evidence presented to indicate the ring‐closure proceeds via electrophilic attack of Vilsmeier reagent on intermediate chlorenamine.
Synthesis of indazole C‐nueleosides and analogues
Authors: Alonso G. , Garcia‐Abbad E. , Garcia‐Lòpez M. T. , Stud M.
Published: April 2009

1‐Deoxy‐1‐diazo‐3,6‐anhydro‐4,5,7‐tri‐O‐benzoyl‐D‐allo‐heptulosc (III) has been prepared from 2,5‐anhydro‐3,4,6‐tri‐O‐benzoyl‐D‐allonic acid. 1,3‐Dipolar cycloaddition of III to benzyne afforded the indazole C‐nucleoside analog V. Cycloaddition of methyl 6‐deoxy‐6‐diazo‐2,3‐O‐isopropylidene‐β‐D‐ribohexofuranosid‐5‐ulose (IV) to the benzyne generated from 5‐methyl‐anthranilic acid gave a mixture of the β‐isomeric C‐glycosylindazoles VI and VII along with traces of the corresponding α‐anomers VIa and VIIa. Finally, a multistep transformation of the acyclic carbohydrate moiety of 2,3,4,5‐tetra‐O‐acetyl‐1‐(indazol‐3‐yl)‐keto‐D‐ribopentulose (I, R = H, n = 3, D‐ribo) led to the C‐nucleoside indazole, 3‐(2,3‐O‐isopropylidene‐β‐D‐ribofuranosyl)‐indazol (X), as the major product.
Homolytic aromatic substitution of heterocyclic compounds. Part XIII. Arylation and heteroarylation of coumarin and benzo[b]furan using triazenes as the source of radicals. An experimental and theoretical study
Authors: Vernin Gaston , Coen Serge , Metzger Jacques , Párkányi Cyril
Published: April 2009

The homolytic arylation (substituents in the phenyl radical: none, p‐methyl, p‐fluoro, p‐chloro, p‐bromo, o‐chloro, 2,4‐dichloro, 3,5‐dichloro, 2,3,4‐trichloro, 2,3,5‐trichloro, o‐carbomethoxy, p‐carboethoxy, and o‐phenyl) and heteroarylation (2‐thiazolyl, 2‐benzothiazolyl, 3‐pyridyl) of coumarin and benzo[b] furan has been studied. The radicals were generated by thermal decomposition of the corresponding 1,3‐diaryltriazenes in the presence of isoamyl nitrite. Homolytic substitution of coumarin takes place exclusively in the position 3, in agreement with the prediction based on SCF‐MO free valences. In the case of benzo[b]furan, all the reactivity indices (F, Sr, and Ar) predict the position 2 to be most reactive, in agreement with the experimental results. Comparison of the mass spectra of the products indicates similarities between the spectra of arylcoumarins and arylbenzo[b]furans and the existence of a common intermediate in their fragmentation pattern, viz., the benzo[b]furan cation radical.

One of the authors (G.V.) wishes to thank Prof. A. Maquestiau (Mons, Belgium) for useful suggestions concerning mass spectrometry. One of the authors (CP.) should like to thank the Ministere de l'Education Nationale, le Secretariat d Etat aux Universités, Paris, for a visiting professorship, and the National Science Foundation, Washington, D. C. for a travel grant. Also, the authors wish to express thanks to Mrs. G. Vernin for her careful technical assistance.
Synthèse de nouveaux alkyl‐2 et ‐3 tétrahydrofurannes et ‐pyrannes
Authors: Montaudon E. , Thèpénier J. , Lalande R.
Published: April 2009

De nouveaux alkyl‐2 et ‐3 tétrahydrofurannes et ‐pyrannes possédant ou non une ramification sur le carbone 1 de la chaǐne latérale sont synthétisés et décrits. Les préparations proposées sont généralisables. Parmi les composes connus de ce type, très rares sont ceux dont le carbone 1 de la chame latérale est tertiaire ou quaternaire.
N‐acyl‐N‐formylcarbamates. A new class of carbamate derivatives
Authors: Graziano M. L. , Iesce M. R. , Scarpalixs R.
Published: April 2009

N‐Acyl‐N‐formylcarbamates III can be prepared in good yields by singlet oxygen oxidation of 5‐unsubstituted 4‐alkoxyoxazoles I. They are photo‐ and thermo‐stable and sensitive to hydrolysis under very mild conditions. In contrast 4‐unsubstituted 5‐alkoxyoxazole V reacts with singlet oxygen to give oxamate VII via dioxazole VI.
Nitrogen bridgehead compounds VIII . Ring transformations IV . Synthesis and reactions of 2,3‐Cycloalkylene‐4H‐pyrido [1,2‐a] pyrimidin‐4‐ones
Authors: Bernàth G. , Fülöp F. , Hermecz I. , Mészáros Z. , Tóth G.
Published: April 2009

By condensing alicyclic β‐ketocarboxylates with substituted 2‐aminopyridines in polyphosphoric acid or phosphoryl chloride‐polyphosphoric acid, numerous 2,3‐tri‐, tetra‐, penta‐ and hexamethylene‐4H‐pvrido[1,2‐a]pyrimidin‐4‐ones were synthesized for pharmacological purposes. The stability and several reactions of the title compounds were studied. The 6‐substituted‐4H‐pyrido[1,2‐a]pyrimidin‐4‐ones were transformed into 1,8‐naphthyridines in good yields independent of the ring size of ring C. The characteristic differences in the ir and uv spectra of the pyrido‐pyrimidines and the corresponding naphthyridines are discussed. Catalytic hydrogenation of the pyrido[1,2‐a]pyrimidin‐4‐ones furnished the corresponding 6,7,8,9‐tetrahydropyrido‐[1,2‐a]pyrimidin‐4‐one derivatives. It was found that the A and C rings attached to the pyrirnidinone ring in solutions of unsubstituted tetrahydropyrido[1,2‐a]pyrimidin‐4‐ones are flexible, whereas in the 6‐methyl derivatives the conformer containing the 6‐methyl group in axial position predominates.
An improved procedure for the preparation of 9‐β‐D‐Arabitiofuranosyl‐2‐ñuoroadenine
Authors: Montgomery John A. , Clayton Sarah D. , Shortnacv Anita T.
Published: April 2009

An improved procedure for the preparation of 9‐β‐D‐arabinofuranosyl‐2‐fluoroadenitie (11) utilizing the readily available 2,4,5,6‐tetraaminopyrimidine (1) is described; the overall yield based on the arabinosugar was quadrupled.
Synthesis of some 3‐substituted quino[3,2‐c][1,8]naphtyridines. A new heterocyclic ring system
Authors: da Settimo Antonio , Prirnofiore Giampaolo , Livi Oreste , Ferrarini Pier Luigi , Spinelli Silvano
Published: April 2009

Isatoic acid reacts with 7‐mcthyl‐2,3‐dihydro‐1,8‐naphthyridin‐4(1H) one (8) to give 3‐methyl‐5,6‐dihvdroquino[3,2‐c][1,8]naphthyriclin‐7‐carboxylic acid (9a), which was transformed into the 3‐methylquino[3,2‐c][1,8]naphthyridine (7a) by refluxing with copper chromite in quinoline. The same product (7a) was also obtained by aromatization of the 3‐methyl‐5,6‐dihydroquino‐[3,2‐c][1.8]naphthvridine (10a), prepared by condensation of the ketone (8) and o‐aminobenzaldehyde. Other 3‐substituted quino[3,2‐c][1,8]naphthyridines (7b,c,d,e), which contain a new heterocyclic, ring structure, have been prepared using o‐aminobenzaldehyde and 7‐sub‐stituted‐2,3‐dihv dro‐1,8‐naphthyridin‐4(1H) ones (12 and 13) as starting materials. Also, the preparation of the parent nucleus (7f) is described.
Synthesis of 5‐methyl‐1,3,2‐benzodithiazoles
Authors: Chen Chin H. , Donatelli Barbara A.
Published: April 2009

The novel helerocycles 5‐methyl‐1,3,2‐benzodithiazoles (7) were prepared in 30–50% yields from toluene‐3,4‐dithiol (6) and appropriate primary amines in the presence of 2 equivalents of triethylamine under high‐dilution conditions. These compounds, which exhibit one reversible oxidation potential around +0.90 V vs. SCE, serve as a model study in the quest of synthesizing a new donor, the “boron‐nitrogen” analog of tetrathiafulvalene (BNTTF).
A general synthesis of alkyl 6‐substituted‐pyrazolo‐[3,2‐c] ‐s‐triazolo‐7‐carboxylates
Authors: Stanovnik Branko , Tišler Miha , Kirn Branko , Kovač Igor
Published: April 2009

A general synthesis of alkyl 6‐methyl‐ and 6‐phenylpyrazolo[3,2‐c]‐s‐triazolo‐7‐carboxylates by photochemical Wolf rearrangement of 6‐methyl‐ and 6‐phenyl‐7‐diazo‐8‐oxo‐s‐triazolo‐[4,3‐b]pyridazine in an alcohol is described.
Tricyclic chemistry. Synthesis and chemistry of a novel polyheterocycle
Authors: Rokach J. , Girard Y. , Atkinson J. G. , Rooney C. S.
Published: April 2009

The photochemical reaction of 1 with acrylonitrile gave the cyclobutane adducts II and III, which on treatment with base afforded a novel polycyclic structure IV. Reduction of IV with LAH followed by Eschweiler‐Clarke methylation yielded the polyheterocyclic structure VI.
Photochemical reactions of 3‐methyl‐4‐nilro‐5‐styrylisoxazole in solution, in the solid slate and adsorbed on silica gel
Authors: Donati D. , Fiorenza M. , Sarti‐Fantoni P.
Published: April 2009

The pholoreactivity of 3‐melhyl‐4‐nitro‐5‐styrylisoxazole in solution and adsorbed on silica gel was studied and the photodimers obtained were identified. The structures of the pholoproduels were assigned on the basis of mass and nmr spectra and chemical behavior. Irradiation of the title compound adsorbed on solid or slurry silica gel leads to the same photoproducts obtained from the solution but with a different yield.
Synthesis of two novel bicyelic systems, imidazo[1,5‐D]‐as‐triazine and imidazo[1,2‐d]‐as‐triazine
Authors: Paul Rolf , Menschik Judith
Published: April 2009

4‐Imidazolecarboxyaldehyde was condensed with methyl dithiocarbazinate and with ethyl carbazate, the resulting hydrazones were subjected to thermolysis in diphenyl ether at 175–240, to give imidazo[1,5‐d]‐as‐triazine‐4(3H)thione and imidazo[1,5‐d]‐as‐triazin‐4(3H)one, respectively. A number of 2‐, 5‐, and 2,5‐substituted 4‐imidazolecarboxaldehydes were also carried through this scheme. The same sequence of reactions with 2‐imidazolecarboxaldehyde gave the novel system imidazo[1,2‐d]‐αs‐triazine‐5‐(6H)‐thione. Upon treatment with sodium hydride and methyl iodide, imidazo[1,5‐d]‐as‐triazine‐4(3H)thione and imidazo[1,2‐d]‐as‐triazine‐5(6H)‐thione gave 4‐methylthioimidazo[1,5‐d]‐as‐triazine and 5‐methylthioimidazo[1,2‐d]‐as‐triazine, respectively. Displacement of the thiomethyl group was achieved with a selection of amine reagents in both of the above cases.
Heterocyclic compounds. XI. Potential post‐coital antifertility agents
Authors: Manhas M. S. , Amin S. G. , Sharma S. D. , Dayal B. , Bose Ajay K.
Published: April 2009

A series of heterocyclic analogs of diarylethylene and triarylethylene were synthesized as potential anti‐implantation agents. Tested in rats as oral, post‐coital antifertilily agents, a few of our compounds showed some activity.
1,3‐Dipolar cycloadditions. Reactions of nitrile imines with 1,2‐disubstituted alkenes
Authors: Chiericato Marco , Dalla Croce Piero , Carganico Germano , Maiorana Stefano
Published: April 2009

Nitrile imines react with 1‐phenylsulphonyl‐2‐benzoyl (or methoxycarbonyl)alkenes to give 4‐phenylsulphonyl‐5‐benzoyl (or methoxycarbonyl) substituted pyrazolines. The cycloaddition regioselectivity is discussed in terms of Frontier Orbital energies and coefficients.
Reaction of thebaine with dinitrogen tetroxide
Authors: Archer Sydney , Osei‐Gyimah Peter
Published: April 2009

Treatment of thebaine with dinitrogen tetroxide gave a mixture of 14β‐nitrocodeinone (23%) and 8‐nitrothebaine (7%).
Acid‐catalyzed rearrangements of 6‐(p‐tolyhydrazino)‐2‐thiouraeil
Authors: Wright G. E. , Gambino J.
Published: April 2009

The action of acid on 6‐(p‐tolylhydrazino)‐2‐thiouracil gives appreciable amounts of the stable Fischer intermediate, 5‐(2 ‐amino‐5 ‐tolyl)‐6‐amino‐2‐thiouracil. This compound undergoes intramolecular cyclization at high temperatures, and represents the first reported isolation of a diamine intermediate derived from a Fischer‐type indolization reaction.
Chemical conversion of uridine to 8,5′‐O‐cyclo‐3‐deazaguanosine
Authors: Tanaka Hiromichi , Veda Tohru
Published: April 2009

Treatment of 1‐(2,3‐O‐isopropy lidene‐β‐D‐ribofuranosyl)‐2‐oxo‐4‐imidazoline‐4‐carboxylic acid methyl ester with formaldehyde gave the 5‐hydroxymethyl derivative which, after aeetylalion, gave the 5‐eyanomelhyl derivative by treatment with tetra‐n‐butylammonium cyanide. The 2,5′‐O‐cyclo derivative of the 5‐cyanomethylimidazole‐4‐carboxylate was converted to the title compound by treatment with ammonia. The present sequence of reactions furnished the chemical conversion of uridine to a 3‐deazaguanosine via the imidazole nucleoside as the intermediate.
The chemistry of 2H‐3,1‐benzoxazine‐2,4‐(1H)dione (isatoic anhydride) 3. One step synthesis of 2,3‐dihydro‐4,1,6‐benzoxadiazonine‐5,7‐(1H,6H)diones
Authors: Barcza Sandor , Coppola Gary M. , Shapiro Michael J.
Published: April 2009

Reactions of N‐haloalkylisatoic anhydrides with amines to produce piperidinobenzamides (2), pyrrolidinobenzamides (4 and 5), and 2,3‐dihydro‐6‐methyl‐4,1,6‐benzoxadiazonine‐5,7‐(1H,6H)diones (10) are described. Spectral data are also discussed.
Polymorphic behavior and melting points of certain benzocrown ether compounds
Authors: Stott Paul E. , Mccausland Calvin W. , Parish W. Wesley
Published: April 2009

Freshly prepared samples of dibenzo‐24‐crown‐8 and 4‐t‐butylbenzo‐15‐crown‐5 were found to have melting points which varied significantly from those origionally reported in the scientific literature. Samples prepared for the origional report were obtained, and were compared with the new samples. The origional report was found to be in error and the corrected values are provided. Dibenzo‐24‐crown‐8 was found to exist as at least three polymorphs. One of these is a glass. The other two are crystalline, but have identical melting points. It was discovered that the less stable form is thermally converted to the more stable form at temperatures below its melting point.
Alkyl nitrate nitration of active methylene compounds. Nitration of 1‐methyl4‐piperidone, 1‐methyl‐2‐pyrrolidinone and 1,3‐dimethyl‐2‐pyrrolidinone
Authors: Feuer Henry , Blecker Lamarr R. , Jans Robert W. , Frost John W.
Published: April 2009

The reaction of 1‐methyl‐4‐piperidone (1) with amyl nitrate in the potassium tert‐butoxidetetrahydrofuran system gave dipotassium 5‐methyl‐2‐oxo‐1,3‐piperidinedinitronate (4) in 78% yield. Similar treatment of 1‐methyl‐2‐pyrrolidinone (2) afforded potassium 3‐methyl‐2‐oxopyrrolidinenitronate (7) in 85% yield. In contrast, the nitration of 1,3‐dimethyl‐2‐pyrrolidinone (3) led to opening of the lactam ring with the formation of amyl 2‐aza‐2‐methyl‐5‐nitrohexanoate (10) in 40% yield.

Acidification of disalt 4 did not cause ring opening but gave the dipolar ion of 1‐methyl‐3‐nitro 4‐hydroxy‐5‐aci‐nitro‐Δ3‐tetrahydropyridinium (6).
Thiazolidinone arylhydrazones. Ring cleavage and alkylation of the 5‐arylhydrazone derivatives of rhodanine and isorhodanine
Authors: Kassab Nazmi A. , Abd Allah Sanaa O. , Elbahaii Said A.
Published: April 2009

The 5‐aryihydrazone derivatives of rhodanine and isorhodanine were subjected to the action of hydrazine hydrate to afford the arylhydrazonomercaptomethyltriazolinthione and ‐triazolinone derivatives 3 and 4, respectively. Treatment of 1 with benzylamine afforded thioxalic acid dibenzylamide 5. On the other hand, treatment of 2 with the same reagent afforded the corresponding benzylamino derivatives 6. Alkylation of 1 and 2 with ethyl bromoacetate and chloroacetamide yielded the corresponding S‐alkyl derivatives 7 and 8, respectively.
Synthesis in the diazasteroid group X. A synthesis of 8,12‐diaza‐D‐homosteroid
Authors: Yamazaki Takao , Takahata Hiroki , Hama Yoko , Takano Yoshiaki , Nagata Masanori , Castle Raymond N.
Published: April 2009

The condensation of 1‐aminoethyl‐6,7‐dimethoxy‐1,2,3,4‐tetrahydroisoquinoline 1 with 1,2‐cyclohexanedione 2 gave the 8,12‐diaza‐D‐homosteroid system 3, which was reduced with Adams' catalyst followed by acetic anhydride acetylation to afford the 8,12‐diaza‐D‐homosteroids 4a,b.
Synthesis of 1,3‐disubstituted hydantoins as possible anticonvulsants
Authors: Joshi Puran C. , Parmar Surendra S. , Rastogi Vinai K.
Published: April 2009

Seven newer 1,3‐disubstituted hydantoins (17–23) were synthesized from 4‐alkoxyanilines. The anticonvulsant activity of these substituted hydantoins and their precursor carbamides (10–16) was reflected by their ability to provide 28–80% and 30–70% protection, respectively, against pentylenetetrazol‐induced convulsions in mice. In general, substituted hydantoins possessed greater anticonvulsant activity than their corresponding precursor carbamides.
Assignments of the chemical shifts of carbon‐13 nuclear magnetic resonance spectra of some 2‐methyl‐3‐(3,4‐dimethoxy/dihydroxyphenylethyl)‐4‐quinazolones
Authors: Singh Shiva P. , Parmar Surendra S. , Farnum Sylvia A.
Published: April 2009

The 13C nmr chemical shifts of a series of 2‐methyl‐3‐(3,4‐dimethoxy/dihydroxyphenylethyl)‐4‐quinazolones are reported. The carbon resonances have been assigned on the basis of chemical shift theory, intensity of the signals, multiplicities generated in SFORD spectra and the comparison with the structurally related compounds.
Chemistry of benzo[b]furan. V.. Synthesis of substituted thia‐analogs and oxa‐analogs of dihydrorutecarpine and evodiamine
Authors: Shafiee A. , Mohammadpour‐Toiserkani M.
Published: April 2009

Cycloaddition of 3,4‐dihydrobenzo[b]thieno[2,3‐c]pyridine (6) with the sulfinamide anhydride 9 (R = H) afforded the thia‐analog of dihydrorutecarpine (2a). Condensation of the imine 6 with the sulfinamide anhydride 9 (R = CH3) gave the thia‐analog of evodiamine (2b). Starting from 1‐methyl‐3,4‐dihydrobenzo[b]thieno[2,3‐c]pyridine (12) and 1‐methyl‐3,4‐dihydrobenzo[b]furo[2,3‐c]pyridine (14), a series of 3‐methyl derivatives of thia‐analogs of dihydrorutecarpine and evodiamine (2c‐2i) and oxa‐analogs of dihydrorutecarpine and evodiamine (1a‐1g) were similarly prepared.
A new synthesis of benzothiopyrano[4,3,2‐de]quinazolines
Authors: Hollins Richard A. , Lima Maria T. L.
Published: April 2009

The synthesis of benzothiopyrano[4,3,2‐de]quinazolines (1a‐c) from 1‐chloro‐4‐methylthioxanthone is described.
Diazo‐, azo‐, and azidoazoles. V. MNDO calculations on the 2‐azidoimidazole/imidazo[1, 2‐d]tetrazole equilibrium
Authors: Olivella Santiago , Vilarrasa Jaume
Published: April 2009

Calculations are reported for the cyclization of 2‐azidoimidazole and its anion to the corresponding pentaazapentalenes using the recently developed MNDO semiempirical SCF‐MO method. The bicyclic anion is predicted to be 16.9 kcal/mole relatively more stable than the neutral bicyclic molecule. The shifting of the equilibrium to the tetrazole form in the case of the anion is mainly attributed to the dercalization of the negative charge on the tetrazole moiety of the bicyclic system.
Stereospecific synthesis and carbon‐13 nmr spectra of 1,4‐epoxydecahydronaphthalenes
Authors: Rose Charles B. , Taylor Stephen K.
Published: April 2009

The stereoselective synthesis of cis‐fused 1,4‐epoxydecahydronaphthalenes from transannular reactions of medium‐ring compounds is described. The carbon‐13 nmr spectra of both are reported, and assignments of the various resonances have been made based on model compounds and off‐resonance decoupling experiments.
Polyazasteroids II.. 1,2,4‐Triazolol[3′,4′:2,3]pyrimido[4,5‐c]quinolin‐ 11(12H)ones, imidazo[2′,1′:2,3]pyrimido[4,5‐c]quinolin‐11(12H)ones and 2,3‐dihydroimidazo[2′,1′:2,3] pyrimido[4,5‐c]quinolin‐11(12H)ones
Authors: Lalezari I. , Sadeghi‐Milani S.
Published: April 2009

Starting with 2‐substituted quinoline‐3,4‐dicarboxylic acids, a series of substituted 1,2,3,4‐tetrahydropyrimido[4,5‐c]quinolinone‐3‐thiones were obtained. The latter compounds were converted to the three novel polyazasteroid series: 1,2,4‐Triazolo[3′,4′:2,3]pyrimido[4,5‐c]‐quinolin‐11(12H)ones, imidazo[2′,1′:2,3]pyrimido[4,5c]quinolin‐11(12H)ones and 2,3‐dihydroimidazo[2′,1′:2,3]pyrimido[4,5‐c]quinolin‐11(12H)ones. The intermediate 3‐hydrazino‐1,2‐dihydropyrimido[4,5‐c]quinolinones and nitrous acid gave the 3‐azido derivatives rather than the tetrazolo compounds.
Reaction of tetraoxopyrrolo [2,3‐d] pyrimidines, isatin analogues, with o‐phenylenediamine
Authors: Bernier Jean‐Luc , Hénichart Jean‐Pierre
Published: April 2009

In the course of general studies on new antitumor tetracyclic intercalating agents, the condensation of o‐phenylenediamine with two new tetraoxopyrrolo[2,3‐d]pyrimidine derivatives has been carried out. The structure of the reaction products as arylketimines has been elucidated and mass spectral fragmentations are discussed.
Preparation of macrocyclic thioether‐diester compounds of fourteen‐seventeen ring members
Authors: Bradshaw Jerald S. , Campbell Mark L. , Hassell Lewis A. , Baxter Jae K.
Published: April 2009

A series of macrocyclic thioether diester compounds of fourteen‐seventeen‐membered rings have been prepared from oxalyl, malonyl, substituted malonyl, succinyl, and substituted succinyl, chlorides and various dithiaglycols (compounds 1–12). A twelve‐membered macrocyclic thioetherdithiolester (compound 13) was also prepared from thiadiglycolyl chloride and 2‐mercaptoethyl sulfide.
[1] Benzofuro[2,3‐d] pyridazines. V. Etude de l'oxo‐4 tetrahydro‐1,2,3,4[1] benzofuro[2,3‐d] pyridazine
Authors: De Sévricourt Michel Cugnon , Godard Anne‐Marie , Robba Max
Published: April 2009

Engagée dans des réactions de substitution électrophile, l'oxo‐4 tétrahydro‐1,2,3,4[1]benzofuro[2,3‐d]pyridazine (1) conduit à des tétrahydrobenzofuropyridazones monosubstituées (sur N2) ou disubstituées (sur N2 et N3). Les structures des dérivés obtenus sont déterminées par l'étude des spectres ir et de rmn ainsi qu'au moyen de synthèses univoques.
Mononuclear heterocyclic rearrangements. Part 12. Rearrangement of 1,2,4‐oxadiazoles into indazoles
Authors: Vivona Nicolò , Cusmano Giuseppe , Macaluso Gabriella , Frenna Vincenzo , Ruccia Michele
Published: April 2009

The first example of a mononuclear heterocyclic rearrangement involving an XYZ = CCN side‐chain sequence is reported. The 3‐(o‐aminophenyl)‐, and 3‐(o‐methylaminophenyl)‐5‐methyl‐1,2,4‐oxadiazoles (3a,b) gave a thermally induced rearrangement into 3‐acylaminoindazoles (4a,b). On the other hand, the 3‐(o‐acetylaminophenyl)‐5‐methyl‐1,2,4‐oxadiazole (3c) produced a base induced rearrangement into 3‐acetylaminoindazole (4a).
Synthesis of 4H‐furo[3,2‐b]indole derivatives. III. Preparation of 4H‐furo[3,2‐b]indole‐2‐carboxylic acid derivatives
Authors: Tanaka Akira , Yakushijin Kenichi , Yoshina Shigetaka
Published: April 2009

Methyl or ethyl 4H‐furo[3,2‐b]indole‐2‐carboxylates (Va,b) were prepared from deoxygenation of methyl or ethyl 5‐(2‐nitrophenyl)‐2‐furoates (IIIa,b) and thermolysis of methyl or ethyl 5‐(2‐azidophenyl)‐2‐furoates (VIIIa,b). 4H‐Furo[3,2‐b]indole‐2‐carboxylic acid amides (XIa‐h) were obtained by the reaction of 4H‐furo[3,2‐b]indole‐2‐carboxyl chloride (X) with the appropriate amines.
Ammonolysis of 3‐hydroxypicolinic acids. A correction and illustration of the use of 13C Nmr OH/OD isotope shifts
Authors: Moore George G. I. , Kirk Alan R. , Newmark Richard A.
Published: April 2009

Ammonolysis of 3‐hydroxy‐6‐methylpicolinic acid (1a) has been reported to give 3‐amino‐6‐methylpicolinic acid. However, on heating 3‐hydroxypicolinic acid with ammonia at 200°, the product proved to be the known 3‐hydroxypicolinamide. 13C Nmr OH/OD isotope shifts in DMSO show that ammonolysis of 1a gives not 2a, but instead 3‐hydroxy‐6‐methylpicolinamide.
Central nervous system depressants. 15. 1,4‐benzodiazepines
Authors: Moffett Robert Bruce , Kamdar Bharat V.
Published: April 2009

A number of 5‐phenyl‐1,4‐benzodiazepines and a few 2‐phenyl‐1,4‐benzodiazepines were prepared and screened for central nervous system activity in mice. Some were highly active. An unusual substitution of 7‐chloro‐1,3‐dihydro‐5‐phenyl‐2H‐1,4‐benzodiazepin‐2‐one by trichloro‐acetylisocyante is reported.