bluuebunny/crossref_metadata_2025 huggingface dataset:
Aminomethyl psoralens. Electrophilic substitution of hydroxymethylphthalimide on linear furocoumarins
Authors: Heindel Ned D. , Choudhuri Mridula , Ressner Joel , Foster Natalie
Published: April 2009

A new synthetic route to aminomethylpsoralens, substituted on the furan‐ring, has been developed by electrophilic substitution of N‐hydroxymethylphthalimide and subsequent hydrazinolysis. Hydroxy and methoxy activating functions on the psoralens lead to multi‐site substitution and the products of these phthalimido‐methylations resist simple cleavage with hydrazine. The two‐step introduction of a single CH2NH2 group is successful in psoralens containing only methyl substituents.
Synthesis of some 3‐alkenyl‐4‐oxo‐1‐phenyl‐5,6‐dihydro‐1H,4H, ‐pyrano[2,3‐C]pyrazole derivatives
Authors: Chantegrel Bernard , Nadi Abdel‐Ilah , Gelin Suzanne
Published: April 2009

The title compounds were prepared from 3‐alkenyl‐1‐phenyl‐2‐pyrazolin‐5‐one derivatives and α,β‐unsaturated acyl chlorides as potential cardiotonic agents.
Antimykotische wirkstoffe. XX . Fluorierte 2‐(4‐toluidino)pyrimidine
Authors: Kreutzberger Alfred , Gillessen Jutta
Published: April 2009

Aus der Kondensation von 4‐Tolylguanidin (1) mit den β‐Diketonen2a‐fgehen die fluorierten 2‐(4‐Toluidino)pyrimidine3a‐fhervor. Strukturtyp3zeichnet sich durch antimykotische Wirkung aus.
Substitution directe de l'azote N‐9 de la théophylline
Authors: Lefebvre Alain , Rips Richard , Martine Alain , Lespagnol Charles
Published: April 2009

La bis (chloro‐2 éthyl)amino‐8 théophylline (1) se cyclise en milieu alcalin en deux imidazo‐purines: une imidazo[1,2‐e]purine 2A (cyclisation en N‐9) et une imidazo[2,1‐f]purine 2B (cyclisation en N‐7). La structure de chaque composé a été déterminéd par spectrographie et confirmée par synthése univoque. La synthése d'une pyrrolo[2,1‐f]purine, nouvel hétérocycle, est décrite.
Some observations on the formation of 1‐hydroxyindoles in the leimgruber‐batcho indole synthesis
Authors: Clark Robin D. , Repke David B.
Published: April 2009

The factors influencing the formation of 1‐hydroxyindoles in the catalytic hydrogenation of β‐dimethylamino‐2‐nitrostyrenes (Leimgruber‐Batcho indole synthesis) have been investigated. Significant amounts of 1‐hydroxyindoles were obtained only when the β‐dimethylamino‐2‐nitrostyrene was substituted with an electron‐withdrawing group at the 5 or 6 position. The proportion of 1‐hydroxyindole formed relative to the normal indole product was found to increase as both the amount of catalyst and hydrogen pressure were decreased.
Synthesis and anticonvulsant activity of 1‐aryl‐3‐methylene‐2‐pyrrolidinone adducts
Authors: Kornet Milton J.
Published: April 2009

Reaction of 1‐aryl‐3‐methylene‐2‐pyrrolidinones with several active hydrogen compounds resulted in a Michael addition to give the title compounds. The compounds were screened in the maximal electroshock seizure and subcutaneous pentylenetetrazol seizure threshold tests for anticonvulsant activity and in the rotorod test for neurotoxicity in mice. Several compounds displayed anticonvulsant activity, but only at the high dose levels of 300 or 600 mg/kg.
Synthesis and spectroscopic properties of some new N,N'‐disubstituted thiorueas of potential biological interest
Authors: Sarkis George Y. , Faisal Essam D.
Published: April 2009

Thirty‐six new N,N'‐disubstituted thioureas have been synthesized by the reaction of phenyl‐, p‐fluorophenyl‐ and benzoylisothiocyanates with various substituted anilines, aminopyridines and 4‐aminoquinolines. The uv, ir and nmr spectral data are presented and discussed.
Studies on 5‐arylidene‐3‐phenyl‐2‐methylmercaptohydantoins
Authors: Kadry Azza M. , Mansour Salwa A.
Published: April 2009

The action of ammonium acetate on 5‐arylidene‐3‐phenyl‐2‐methylmercaptohydantoins 1g,h in acetic acid led to the formation of the 5‐arylidene‐3‐phenylhydantoin derivatives 4a,b. In absence of a solvent, ring opening and rearrangement took place with the formation of the 5‐arylidene‐N2‐phenylglycocyamidine derivatives 7a‐c. Compounds 7a‐c reacted with methyl iodide to afford the corresponding 3‐methyl derivatives 9a‐c. The structures of the synthesised products were established and the mechanism proposed for the rearrangement reaction was discussed.
3‐Alkylthio and 3‐aminopyrazolo[3,4‐D]pyridazines. Ring contraction of pyridazino[4,5‐e][1,3,4]thiadiazines via extrusion of sulfur
Authors: Kaji Kenji , Nagashima Hiromu , Ohhata Yasushi , Tabashi Keizo , Oda Hirohisa
Published: April 2009

Reaction of 4‐chloro‐2‐methyl‐5‐(1‐methylhydrazino)‐3(2H)‐pyridazinone (1) with carbon disulfide followed by alkylation yielded 2‐alkylthio‐4H‐pyridazino[4,5‐e][1,3,4]thiadiazine derivatives 2. Oxidative cyclization of 5‐(4‐substituted 1‐methylthiosemicarbazido)‐3(2H)‐pyridazinone derivatives 4 with N‐bromosuccinimide also gave 2‐substituted amino‐4H‐pyridazino[4,5‐e][1,3,4]thiadiazine derivatives 5. Heating of 2 and 5 resulted in ring contraction to afford the corresponding pyrazolo[3,4‐d]pyridazine derivatives 6, 7 via sulfur extrusion. A possible mechanism for the desulfurization reaction is discussed, comparing with a structural difference between a type of pyridazino[4,5‐e][1,3,4]thiadiazine (2,5) and another one (9,11,13,15).
P‐N compounds.25. Phosphaminimides.1. Synthesis and bioevaluation of a derivative of tetrahydro‐2H‐1,3,4,2‐oxadiazaphosphorinium inner salt
Authors: Cates Lindley A. , Li Ven‐Shun , Basrur Jyoti P. , Saddawi Bashir H. , Alkadhi Karim A.
Published: April 2009

2‐Phenoxy‐4,4‐dimethyltetrahydro‐2H‐1,3,4,2‐oxadiazaphosphorinium 2‐oxide inner salt, the first known cyclic phosphaminimide, was synthesized by dehydroiodination of its hydrazinium salt. The corresponding 2‐phenyl derivative was unstable and not isolated. The 2‐phenoxy and 2‐phenylphosphorinium iodides and their precursors produced weak inhibition of sympathetic ganglionic transmission. The phosphaminimide caused a slight potentiation and was also found to be less toxic than its corresponding hydrazinium iodide precusor.
An alternative synthesis of 3‐amino‐1,2,3,4‐tetrahydrocarbazoles
Authors: Bird C. W. , Wee A. G. H.
Published: April 2009

3‐Amino‐1,2,3,4‐tetrahydrocarbazoles are easily prepared from the readily available 3‐hydroxy‐1,2,3,4‐tetrahydrocarbazoles by conversion of the latter to the p‐toluene‐ or methanesulfonate ester, followed by nu‐cleophilic displacement with azide ion. The resulting 3‐azido‐1,2,3,4‐tetrahydrocarbazoles are then catalytically hydrogenated to their 3‐amino counterparts.
Studies on pyrrolidinones. Synthesis of methyl N‐(4‐nitrobenzyl)pyroglutamate
Authors: Rigo Benoǐt , Couturier Daniel
Published: April 2009

Methyl N‐trimethylsilylpyroglutamate is reacted with 4‐nitrobenzyl chloride to yield methyl N‐(4‐nitrobenzyl)pyroglutamate.
Synthesis of monoamino and monohydroxydibenzothiophenes
Authors: Kudo Hirotaka , Castle Raymond N. , Lee Milton L.
Published: April 2009

The synthesis of the four monoaminodibenzothiophenes and the four monohydroxydibenzothiophenes is described.
Synthesis and mass spectral studies of 1‐[5‐chloro‐1‐substituted‐2(1H)‐pyrazin‐2‐on‐3‐yl]‐5‐aryl‐3‐methylpyrazoles
Authors: Bhattacharya B. K. , Eirich F. R.
Published: April 2009

Sixteen new 1‐[5‐chloro‐1‐substituted‐2(1H)‐pyrazin‐2‐on‐3‐yl]‐5‐aryl‐3‐methylpyrazoles V have been synthesized by condensation of 5‐chloro‐1‐substituted‐3‐hydrazino‐2(1H)‐pyrazin‐2‐ones III and 1‐aryl‐1,3‐butanediones IV in dry 1,4‐dioxane. The general mass spectral fragmentation mode of these compounds has been studied.
Fused‐s‐triazino heterocycles. XII. 13H‐4,6,7,8,13a, 13c‐hexaazabenzo‐[de]naphthacene, a new ring system
Authors: Shaw John T. , Babin James E. , Sensenig Lori A. , Acciai Guy F. , Fair Mark C. , Coffindaffer Timothy W. , Westler W. Milo
Published: April 2009

The synthesis of the titled compound is described using 5‐(2‐carboxyanilino)‐2‐methyl‐1,3‐4,6,9b‐pentaaza‐phenalene as starting material.
The reaction between an azomethine and malonyl dichloride
Authors: Sard Howard , Meltzer Peter C. , Razdan Raj K.
Published: April 2009

The reaction of o‐hydroxybenzylideneamine and malonyl dichloride produces coumarin‐3‐carboxanilide.
(Perhalogenmethylthio)heterocyclen. XVIII . Synthese und eigenschaften von halogenierten (perhalogenmethylthio)pyrrolen
Authors: Ceacareanu Dimitru M. , Gerstenberger Michael R. C. , Haas Alois
Published: April 2009

(Trifluormethylthio)pyrrole 1‐5 und (Chlordifluormethylthio)pyrrol 6 lassen sich mit den Chlorierungsmitteln Sulfurylchlorid, Sulfurylchlorid/Siliciumdioxid oder Sulfurylchlorid/Dischwefeldichlorid/Aluminiumtrichlorid in die entsprechenden chlorierten Verbindungen 1a‐d, 2a, b, 3a, b, 4a, 5a und 6a‐c überführen. Die Bromierung mit Brom bzw. Iodierung mit Iod/Kaliumiodid von 2, 3, 4 und 6 liefert die Derivative 2c, d, 3c, d, 4b und 6d bzw. 2e, 3e, f, 4c und 6e. Gemischthalogenierte Pyrrole 3g und h werden aus 3a und Brom bzw. 3a und Iod/Kaliumiodid erhalten. 7, 8 und 9 fallen in geringen Ausbeuten als Nebenprodukte eineger Chlorierungen an.

1H‐, 19F‐NMR‐ und IR‐Spektren werden angegeben.
Studies on pyrrolidinones. Synthesis of 5‐(5‐oxo‐2‐pyrrolidinyl)‐1,3,5‐oxadiazole‐2‐thione derivatives
Authors: Rigo Benoî;t , Couturier Daniel
Published: April 2009

Starting from readily available pyroglutamic esters 1, some new 1,3,4‐oxadiazole‐2‐thione derivatives, bonded to a pyrrolidinone ring were synthesised and characterised by their spectral data.
Oxidative cyclization of some 1,3‐dioximes with lead tetraacetate
Authors: Stephanidou‐Stephanatou J.
Published: April 2009

Oxidation of 1,3‐dioximes 1 with lead tetraacetate gives di‐N‐oxides of pyrazolines 4 or pyrazoles 5 or N‐oxides of oxadiazines 7 as the main reaction products. The reaction mechanism is discussed.
Synthesis of 1,3,4‐thiadiazolo[3,2‐α]pyrimidin‐5‐one and isomeric 7‐one derivatives
Authors: Russo Filippo , Santagati Andrea , Santagati Maria
Published: April 2009

Continuing preceeding studies, designed to obtain derivatives of 1,3,4‐thiadiazolo[3,2‐α]pyrimidin‐5‐one and of the isomeric 7‐one of pharmacological interest, some of the above mentioned compounds were prepared. Their structural identification was obtained by mass spectra.
A new route to N2‐ and N3‐substituted‐2,3‐diaminopyridines. Synthesis of 1‐ and 3‐alkoxycarbonyl‐v‐triazolo[4,5‐b]pyridines
Authors: Zecchini Giampiero Pagani , Torrini Ines , Paradisi Mario Paglialunga
Published: April 2009

Selective protection of the 3‐amino group of 2,3‐diaminopyridine with benzyl chloroformate allows a new synthesis of 3‐methylamino‐ and 3‐amino‐2‐alkylaminopyridines. The preparation of 1‐ and 3‐alkoxycarbonyl‐v‐triazolo[4,5‐b]pyridines is also reported.
Synthesis and mass spectrum of 3‐(3′‐pyridinyloxymethyl)pyridine and polarography of its dialkyl diquaternary salts
Authors: Attalla Moetaz I. , Burnett Geoffrey R. , Summers Lindsay A.
Published: April 2009

3‐(3′‐Pyridinyloxymethyl)pyridine is prepared by reaction of 3‐hydroxymethylpyridine with 3‐bromopyridine and converted to the 1,1′‐dimethyl and 1,1′‐diethyl diquaternary salts with alkyl iodides. The salts are reduced polarographically at a potential (Eo) of about ‐ 1.02 to ‐ 1.10 V in the pH range of 5.5‐8.5.
Preparation of 1,2,5‐thiadiazole‐3‐carboxaldehydes
Authors: Matakas Shuntaro , Kurisu Masayoshi , Takahashi Kazufumi , Tashiro Masashi
Published: April 2009

1,2,5‐Thiadiazole‐3‐carboxaldehydes 1a‐c were prepared by the acid‐catalyzed decomposition of 3‐azido‐methyl‐1,2,5‐thiadiazoles 2a‐c in 68‐83% yields, respectively. Pyrolysis of 2a and 2b afforded the imidazoles 4a and 4b in low yields. NBS‐bromination of 1a and 1b gave the corresponding carboxylic acids 10a and 10b via acid bromides 9. Azides 2a and 2b gave the s‐triazines 8a and 8b on treatment with NBS.
The preparation and oxidative dimerisation of 2‐acetyl‐7‐hydroxy‐1,2,3,4‐tetrahydroisoquinoline. A new approach to tetrahydroisoquinoline synthesis
Authors: Ajao J. F. , Bird C. W.
Published: April 2009

The title compound has been prepared from 1,2,3,4‐tetrahydroisoquinoline via successive nitration, acet‐ylation, reduction and diazotisation. Earlier conflicting reports on the nitration of tetrahydroisoquinoline have been clarified. A better synthetic route, based upon reduction of the corresponding isocarbostyril, has been devised and should be applicable to the obtention of a wide range of tetrahydroisoquinolines. The structure of the neutral product of oxidative dimerisation of 2‐acetyl‐7‐hydroxy‐1,2,3,4‐tetrahydroisoquinoline has been established.
Synthesis of 5H‐tetrazolo[5,1‐c][1,4]benzodiazepines
Authors: Klaubert Dieter H. , Bell Stanley C. , Pattison Thomas W.
Published: April 2009

A three step synthesis of 5H‐tetrazolo[5,1‐c][1,4]benzodiazepin‐11‐ones 8a‐d via the reaction of a substituted benzyl azide and ethyl cyanoformate is described. The derived lactams are converted to the corresponding 11‐thiones 9a‐d and, through the S‐methylated derivatives, to the 11‐amino analogs 11a‐f. All of the described compounds are representatives of a novel ring system.
Synthesis of 2‐substituted 4‐oxo‐5‐nitropyrimidines from methyl 3‐ethoxy‐2‐nitroacrylate and other reactions
Authors: de la Cuesta E. , Avendaño C.
Published: April 2009

Methyl 3‐ethoxy‐2‐nitroacrylate (MENA) (1) has been the subject of study for the development of new syntheses leading to nitro‐substituted heterocycles.
Pyrimidines. LII Synthesis of pyrido[2,3‐d]pyrimidine‐2,4‐diones and pyrido[2,3‐d:6,5‐d']dipyrimidine‐2,4,6,8‐tetrones
Authors: Hirota Kosaku , Kitade Yukio , Senda Shigeo
Published: April 2009

Reactivities of 5‐dimethylaminomethylene‐6‐imino‐1,3‐dimethyluracil hydrochloride (1) toward a variety of active methylene compounds 2 and 5 were investigated. Treatment of 1 with active methylene compounds such as malononitrile and ethyl cyanoacetate in the presence of triethylamine gave pyrido[2,3‐d]pyrimidine‐2,4‐dione derivatives 3. Reaction of 1 with barbituric acids resulted in the formation of pyrido[2,3‐d:6,5‐d′]di‐pyrimidine‐2,4,6,8‐tetrone derivatives 6.
Synthesis of the new ring system, Pyrazolo[3,4‐d][1,3]diazepine. A novel route for the synthesis of azolo[1,3]diazepines
Authors: Acevedo Oscar L. , Krawczyk Steven H. , Townsend Leroy B.
Published: April 2009

A reduction of the nitrile group of 5‐amino‐4‐cyano‐1‐methylpyrazole (3) has provided the very versatile compound 5‐amino‐1‐methylpyrazole‐4‐carboxaldehyde (4). The amino group of 4 was protected using di‐methylformamide dimethylacetal and the aldehyde group was then reacted with trimethylsilyl cyanide to afford the moisture sensitive compound 5‐[[(dimethylamino)methylene]amino]‐4‐[cyano(trimethylsiloxy)‐methyl]‐1‐methylpyrazole (10). The cyano group of the cyanohydrin 10 was reduced using a cobalt boride catalyst to afford an intermediate aminomethyl group which was involved in an in situ annulation. This reaction provided 1‐methyl‐1,4,5,6‐tetrahydropyrazolo[3,4‐d][1,3]diazepin‐4‐ol, a derivative of the new ring system, pyrazolo[3,4‐d][1,3]diazepine.
Fries rearrangement of methoxyphenyl 3‐methylbut‐2‐enoates
Authors: Camps F. , Coll J. , Colomina O. , Messeguer A.
Published: April 2009

Fries rearrangement of 2‐, 3‐ and 4‐methoxyphenyl 3‐methylbut‐2‐enoates 3‐5 in methanesulfonic acid, polyphosphoric acid, aluminum chloride and under photochemical conditions have been studied. The outcome of the reactions was determined by the substitution pattern in the starting products and the reaction conditions used. Under Lewis acid catalysis, acylation accounted for the major components of the reaction mixtures, leading to the formation of indanones and 2,3‐dihydro‐4H‐1‐benzopyran‐4‐ones respectively in the case of o‐ and m‐esters 3 and 5, whereas alkylation to afford dihydrocoumarins was the favored path for p‐ester 5. On the other hand, o‐acylation was in all cases the major reaction course in the photochemical rearrangement.
Pyrido[1,2‐a]benzimidazoles et analogues: Synthese et etude structurale
Authors: Bergerat Isabelle , Galons Hervé , Rabaron Alain , Combet‐Farnoux Claude , Miocque Marcel
Published: April 2009

Les (propynyl‐2)‐1 aminométhyl‐2 benzimidazoles, préparés à partir d'orthodiamines aromatiques, peuvent être transformés avec de bons rendements en pyrido[1,2‐a]benzimidazoles. Le premier temps de la réaction est une hétérocyclisation: les intermédiaires ont été isolés et leur réarrangement étudié. La méthode est applicable à certains azabenzimidazoles.
Studies on alkylpyrazine dianions. Preparation of 5,6,11,12‐tetrahydrocycloocta[1,2‐b:5,6‐b']dipyrazine
Authors: Houminer Yoram , Williams David L.
Published: April 2009

The reaction of 1,2‐bis(3‐methyl‐2‐pyrazyl)ethane (1) with two equivalents of LDA followed by 1,2‐dibromo‐ethylene gave a mixture of two intramolecular ring closure products, 2 and 3, in low yields. A dimer 4 resulting from an intermolecular coupling reaction was also isolated.
Saturated heterocycles. 70 . Application of the seth‐paul‐van duyse equation. 10 . The C  O stretching frequencies and transmission of substituent effects in 5,6‐polymethylene‐2,3,5,6‐tetrahydro‐1,3‐oxazin‐4‐one derivatives
Authors: Perjéssy Alexander , Fülöp Ferenc , Bernáth Gábor
Published: April 2009

The C  O stretching frequencies of twenty‐six cis‐5,6‐polymethylene‐2,3,5,6‐tetrahydro‐1,3‐oxazinone derivatives were measured in tetrachloromethane and in chloroform and correlated with the substituent constants X+(R) in the sense of the modified and extended Seth‐Paul Van Duyse equation. The influence of the fused hydrocarbon ring on the C  O stretching frequency and on the transmission of substituent effects through the six‐membered heterocyclic ring is discussed and compared with that in the previously investigated 5,6‐polymethylenepyrimidin‐4(3H)‐ones and cis‐5,6‐dihydropyrimidin‐4(3H)‐ones.
Reaction of 6‐arylidenehydrazino‐1,3‐dimethyluracils with thionyl chloride leading to purine, thiazolo[4,5‐d]pyrimidine, pyrimido[4,5‐e][1,3,4]thiadiazine, pyrazolo[3,4‐d]pyrimidine, and [1,2,3]thiadiazolo[4,5‐d]pyrimidine derivativese
Authors: Ichiba Misuzu , Senga Keitaro
Published: April 2009

The reaction of 6‐arylidenehydrazino‐1,3‐dimethyluracils with thionyl chloride in benzene afforded purine, thiazolo[4,5‐d]pyrimidine, pyrimido[4,5‐e][1,3,4]thiadiazine, pyrazolo[3,4‐d]pyrimidine, and [1,2,3]thiadiazolo[4,5‐d]pyrimidine derivatives, while the treatment of 6‐(benzylidene‐1′‐methylhydrazino)‐1,3‐dimethyluracil with thionyl chloride in benzene gave 4‐methylpyrimido[4,5‐e][1,3,4]thiadiazine and 1‐methylpyrazolo‐[3,4‐d]pyrimidine derivatives. Plausible mechanisms for the formation of these fused pyrimidines are also described.
Synthesis of a novel series of 3‐substituted [1]benzothieno[3,2‐d]pyrimidine derivatives
Authors: El‐Telbany Farag , Hutchins Robert O.
Published: April 2009

A series of 3‐substituted [1]benzothieno[3,2‐d]pyrimidine derivatives has been synthesized as possible antileukemic agents by condensation of methyl 3‐(ethoxymethylene)amino‐2‐benzothiophene carboxylate (II) with a variety of amines to afford the corresponding 3‐aryl and 3‐alkyl [I]benzothieno[3,2‐d]pyrimidin‐4(3H)‐ones, Ill and IV, respectively. In addition, Mannich reactions of [I]benzothieno[3,2‐d]pyrimidin‐4(3H)‐one (VIII) with formaldehyde and secondary amines gave the expected derivatives, IX. 3‐Amino[I]benzothieno[3,2‐d]‐pyrimidin‐4(3H)‐one (VI) reacted with substituted aromatic aldehydes in the presence of boron trifluoride to yield the corresponding imines VII.
Reactions of β‐sulfenyl α,β‐unsaturated ketones with guanidine, Amidines, and diamines
Authors: Nishio Takehiko , Tokunaga Tatsuhiro , Omote Yoshimori
Published: April 2009

β‐Sulfenyl α, β‐unsaturated ketones 1a‐c reacted with guanidine or amidines to give pyrimidine derivatives 3 in 14‐76% yields. Treatment of ketones 1 with diamines such as ethylenediamine and o‐phenylenediamine afforded the seven‐membered heterocycles, 2,3‐dihydro‐1,4‐diazepine 5 and 2,3‐benzo‐1,4‐diazepines 8a‐c.
Efficient synthesis of 5‐substituted‐4,5‐dihydro‐1,2,4‐triazin‐6‐ones and 5‐substituted‐1,2,4‐triazin‐6‐ones
Authors: Taylor Edward C. , Macor John E.
Published: April 2009

Treatment of methyl α‐(dimethylarninomethyleneamino)carboxylates 1 (from α‐amino acids and dimethylformamide dimethylacetal) with hydrazine gives 5‐substituted‐4,5‐dihydro‐1,2,4‐triazin‐6‐ones 2, which are smoothly dehydrogenated to 5‐substituted‐1,2,4‐triazin‐6‐ones 3 with potassium permanganate in acetone/acetic acid.
Synthesis of novel imidazole‐4,5‐dicarboxylic acid derivatives
Authors: Yasuda Naohiko
Published: April 2009

A convenient general method for the synthesis of unsymmetrical imidazole‐4,5‐dicarboxylic acid derivatives is described. The key intermediates are 5,10‐dioxo‐5H,10H‐diimidazo[1,5‐a:1′,5′‐d[pyrazine‐1,6‐dicarboxylic acid, ‐1,6‐dicarboxylic ester and ‐1,6‐dicarboxamide.
Chemical properties of 2‐isopropylimino‐3‐isopropyl‐5‐methoxy‐Δ4‐oxazoline: Formation of charge‐transfer complexes from an oxazoline
Authors: Drapier J. , Badot J. , Jonius L. , Warin R. , Hubert A. J. , Teyssie Ph.
Published: April 2009

2‐Isopropylimino‐3‐isopropyl‐5‐methoxy‐Δ4‐oxazoline 1 copolymerizes readily by a radicalar mechanism with maleic anhydride, an air and heat sensitive isolable charge‐transfer monomer 2 being formed as intermediate. Similarly, a (more stable) adduct 4 has been prepared from 1 and TCNE. In opposition, acrylic acid adds onto the Δ4‐oxazoline endocyclic double bond giving the acrylate 5. The hydrolysis and hydrogenation of 1 are also reported.
Synthesis of 5,6‐dihydropyrrolo[l,2‐α][3,1,6]thiadiazocines
Authors: Cheeseman G. W. H. , Hawi A. A. , Varvounis G.
Published: April 2009

The title compounds 15‐18 and 26 are prepared by intramolecular cyclisation of the pyrrolylthiols derived from sodium borohydride reduction of N‐aryl‐thiocyanatopyrroles 11‐14 and 25.
Further reactions of 3‐hydroxy‐1(3H)‐isobenzofuranone with amines
Authors: Sloan Kenneth B. , Koch Suzanne A. M.
Published: April 2009

The reaction of 3‐hydroxy‐1(3H)‐isobenzofuranone (III) with 2‐phenylethylamines has been shown to give either monoalkylated VI or dialkylated VII products (prodrugs) depending on the number of equivalents of III used. The monoalkylated products disproprotionated to the dialkylated products unless they were stabilized as salts. In addition, the reaction of III with cytosine and adenine resulted in the formation of N4 and N6‐alkylated products, respectively. The alkylated 2‐phenylethylamines, and cytosine and adenine are representative of a new type of prodrug approach to modifying the physical chemical properties of these two important classes of drugs.
Chemistry of pyrimidine. Proton magnetic resonance study of covalent hydration across the 3,4‐carbon‐nitrogen bond of 5‐substituted pyrimidines
Authors: Kress Thomas J.
Published: April 2009

Pyrimidines containing 5‐substituents which are weakly or strongly electron withdrawing undergo covalent hydration across the 3,4‐carbon‐nitrogen bond in aqueous acid. The degree of hydration was measured by proton magnetic resonance spectroscopy and was found to be dependent on the strength of the acid media and the electron withdrawing power of the 5‐substituent.
Mass spectral fragmentations of 6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,6‐dioxazocin‐2‐ones
Authors: Nishiyama Tomihiro , Maeda Masayuki , Yamada Fukiko
Published: April 2009

The mass spectra of a series of 6‐phenyl‐5,6,7,8‐tetrahydro‐4H‐1,3,6‐dioxazocin‐2‐ones have been examined.
Une nouvelle synthese de β‐enaminoindanones
Authors: Brunerie Pascal , Célérier Jean‐Pierre , Lhommet GÉRard
Published: April 2009

Les (3‐énaminoindanones sont préparées en une seule étape à partir de l'‐chlorométhylbenzoate d'éthyle et de différents β‐énaminoesters cycliques ou acycliques, par action de l'hydrure de sodium en suspension dans le toluène.
Synthesis of pyrazolo[3,2‐c]‐1,2,4‐triazines from N‐(5‐pyrazolyl)‐α‐ketohydrazidoyl halides
Authors: Abdelhamid Abdou O. , Hassaneen Hamdi M. , Shawali Ahmad S.
Published: April 2009

3‐Phenylpyrazole‐5‐diazonium chloride (5) couples with benzenesulfonylacetone (9a), benzenesulfonylacetophenone (9b), ethyl benzenesulfonylacetate 9c, and ethyl benzoylacetate (12b) in ethanol in the presence of sodium acetate at room temperature to afford the pyrazolo[3,2‐c]‐1,2,4‐triazine derivatives 11a and 11b and the acyclic hydrazones 10c and 13 respectively. The products 11a,b and 10c can also be obtained from the reaction of the corresponding hydrazidoyl halides 8a‐c with sodium benzenesulfinate in high yield. The hydrazones 10c and 13 can be cyclised thermally or under the influence of acid into pyrazolo[3,2‐c]‐1,2,4‐triazine derivatives 11c and 14 respectively.
Novel reactions of carbon suboxide. VI. Synthesis of 2‐Oxo‐1‐benzopyran‐ and 2‐oxoquinoline‐3‐carboxylic acid hydrazides
Authors: Bonsignore Leonardo , Loy Giuseppe , Secci Mario , Cabiddu Salvatore
Published: April 2009

A simple, one step synthesis of 2‐oxo‐1‐benzopyran‐ and 2‐oxoquinoline‐3‐carboxylic acid hydrazides from carbon suboxide and hydrazones is described.
The chemistry of 2h‐3,1‐benzoxazine‐2,4(1H)‐dione (isatoic anhydride). 17 Synthesis of 2‐alkyl‐4‐quinolone alkaloids via a one‐step reaction of N‐methylisatoic anhydride with methyl ketone enolates
Authors: Coppola Gary M.
Published: April 2009

Lithium enolates derived from aliphatic methyl ketones react with N‐methylisatoic anhydride (5) at −78° to give 2‐alkyl‐4‐quinolone alkaloids 7 in a single step. The method was used to synthesize both double bond isomers of 1‐methyl‐2‐(8‐tridecenyl‐4(1H)‐quinolinone (8) thereby showing that the alkaloid evocarpine possesses the Z‐olefin stereochemistry 8a. Reduction of 8a provided the alkaloid dihydroevocarpine (16). Compound 16 was also directly prepared from the reaction of 5 with the lithium enolate of 2‐pentadecanone.
The preparation of phenacylpyrazoles, acylpyrazoles, imidazolylisoxazoles and imidazolylpyrazoles from c(α)‐dianions of oximes, phenylhydrazones and acylhydrazones
Authors: Huff Ann M. , Hall Howard L. , Smith Melanie J. , O'Grady Sheila A. , Waters Frank C. , Fengl Richard W. , Welsh Jeffery A. , Beam Charles F.
Published: April 2009

C(α),O‐Dilithiooximes, C(α), N‐dilithiophenylhydrazones, or C(α), N‐dilithioacylhydrazones were prepared in an excess of lithium diisopropylamide (LDA) and condensed with a variety of esters followed by acid‐cyclization to give substituted isoxazoles and pyrazoles.
The 1‐alkoxy‐4‐nitro‐1,2,3‐benzotriazole system
Authors: Maxwell G. , Seybold P. G. , Servé M. P.
Published: April 2009

The 1‐alkoxy‐4‐nitro‐1,2,3‐benzotriazole system was prepared using a phase transfer catalysis procedure. The physical and spectral properties of the system are reported. Molecular orbital calculations on the 1‐methoxy derivative are used to explain the spectroscopic and electronic properties of the system.
Stereochemical studies. Part 67. Saturated heterocycles. Part 52. The mass spectra of some condensed skeleton 1,3‐oxazin‐4‐one derivatives
Authors: Vékey Károly , Tamás József , Fülöp Ferenc , Bernáth Gábor
Published: April 2009

The mass spectrometric behaviour of twenty saturated heterocyclic compounds with a 1,3‐oxazin‐4‐one moiety fused with cis or trans anellation to a cycloalkane ring (C5‐C8) was studied. The roles of the C‐2 and N‐3 substituent(s) were found to be characteristic, while the size of the cycloalkane ring seemed to be unimportant. Some fragmentation processes involving breakdown of the oxazinone ring of the cis or trans isomers displayed significant stereoselectivity. A striking new decomposition process involving significant chlorine elimination from the molecular ion of some 2‐p‐chlorophenyl derivatives was observed and was studied in some detail.
Analogs of 3‐(1‐phenyl‐3‐oxobutyl)‐4‐hydroxycoumarin (warfarin) prepared from substituted salicylic acids
Authors: Obaseki Andrew O. , Steffen James E. , Porter William R.
Published: April 2009

Some derivatives of salicylic acid containing substituents meta to the carboxyl group were used to prepare analogs of the anticoagulant drug warfarin, 3‐(1‐phenyl‐3‐oxobutyl)‐4‐hydroxycoumarin, containing substituents in either the 6‐or 8‐position of the courmarin ring. When the substituent was the hydroxyl group, the resulting products are previously identified metabolites of warfarin. The substituted salicylic acid is first acetylated with acetic anhydride, then either converted to the acid chloride and condensed with diethyl malonate in the presence of sodium hydroxide or converted to the mixed anhydride with formic acid and condensed with ethoxymagnesium diethyl malonate to yield, in either case, the corresponding 3‐carbethoxy‐4‐hydroxycoumarin substituted in the 6‐ or 8‐position of the coumarin ring. These compounds readily condense with benzalacetone to form the corresponding substituted warfarin in the presence of 5 mole % tertiary amine catalyst. This method offers an improved route for the synthesis of 8‐hydroxywarfarin.
Cycloadditions of N‐Aryl‐C‐(trifluoromethyl)nitrilimines with dimethyl fumarate and maleate
Authors: Tanaka Kiyoshi , Maeno Seiji , Mitsuhashi Keiryo
Published: April 2009

The cycloadditions of N‐aryl‐C‐(trifluoromethyi)nitrilimines 1, generated in situ from various precursors, with dimethyl fumarate and maleate are described. N‐Aryltrifluoroacetohydrazonoyl bromides 2 reacted with fumarate in the presence of triethylamine to give the trans‐4,5‐dimethoxycarbonylpyrazolines 4 whereas the reactions with maleate afforded the 4,5‐dimethoxycarbonylpyrazoles 5 as well as 4. In the reactions with the chloride 6 under the more drastic conditions, both fumarate and maleate gave the pyrazole 5a. From thermolysis of the oxadiazaphosphole 8, the trans‐pyrazoline 4a was formed in both cases of fumarate and maleate. The preparation of the cis‐pyrazoline 9 was attempted from 8 and maleic anhydride but 9 was found to be so unstable as to be epimerized under the mild conditions.
Ring‐transformation of 1,2,4‐oxadiazines. Raney nickel hydrogenation of Z‐3‐aryl‐5,6‐dihydro‐5‐(substituted)methylene‐4H‐1,2,4‐oxadiazine derivatives
Authors: Tabei Katsumi , Kawashima Etsuko , Takada Toyozo , Kato Tetsuzo
Published: April 2009

Raney nickel hydrogenation of Z‐3‐aryl‐5‐(ethoxycarbonyl)methylene‐5,6‐dihydro‐4H‐1,2,4‐oxadiazine (1a‐c) affords 2‐aryl‐6‐hydroxymethyl‐4‐pyrimidinone (2) and ethyl (2‐aryl‐4‐oxazolyl)acetate (3). A similar hydrogenation of Z‐5‐arylcarbarnoyl)methylene‐5,6‐dihydro‐3‐phenyl‐4H‐1,2,4‐oxadiazine (1d‐f) gives E‐4‐(arylcarbamoyl)methylene‐2‐phenyl‐2‐oxazoline (5), 4‐(arylcarbamoyl)methyl‐2‐phenyloxazole (6), and Z‐4‐(aryl‐carbamoyl)methylene‐2‐phenyl‐2‐oxazoline (7).
Styryl dyes derived from bis boron diketonates
Authors: Reynolds George A. , Chen Chin H.
Published: April 2009

Bis boron diketonates are prepared from β‐diketones or o‐acylphenols or naphthols with boron trichloride or boron tribromide. The bis boron diketonates that contain methyl groups reacted with some aromatic aldehydes, giving styryl dyes, most of which showed high extinction coefficients.
Facile synthesis of novel 3‐quinoxalinyl‐1,5‐benzodiazepines via ring transformation. Stable tautomers in the 1,5‐benzodiazepin‐2‐one ring system
Authors: Kurasawa Yoshihisa , Okamoto Yoshihisa , Ogura Kuniyoshi , Takada Atsushi
Published: April 2009

Novel 3‐quinoxalinyl‐1,5‐benzodiazepines 4, 5, 6, 9, 10 were synthesized via the ring transformation of 3‐(N,N‐dimethylcarbamoyl)furo[2,3‐b]quinoxaline hydrochloride (1). The 3‐quinoxalinyl‐1,5‐benzodiazepine hydrochlorides 4 and 6 are the tautomers of the N1′‐H (or N5‐H) form and the C3‐H form, respectively, which are stable in solid and solution. However, 4 (NH form) was found to be converted into 6 (C3‐H form) by refluxing in acetic acid. The individual spectral evidences and different reactivity of these tautomers are described.
Synthesis of C‐3 side‐chain carboxylic acid cannabinoid derivatives
Authors: Borne Ronald F. , Mauldin Scott C.
Published: April 2009

Based upon the structural similarities of cannabinoid derivatives which inhibit the biosynthesis of prostaglandins with those of the potent inhibitor, indomethacin, several cannabinoid derivatives possessing C‐3 side chain carboxylic acid functionalities were prepared.
Quninone chemistry. Synthesis of 3‐methoxy[2, 1]benzisoxazoleand 3‐methoxynaphth[2,3‐c]isoxazolequinones
Authors: Torres Tomás , Eswaran S. V. , Schäfer Wolfram
Published: April 2009

[2, 1]Benzisoxazole‐4, 7‐quinones 4 are prepared by an improved method using oxidative amination of 1 to give 2, followed by amine exchange to 3 and cyclization with lead tetraacetate. Naphth[2,3‐c]isoxazole‐4,9‐quinone 7 is obtained from 5 by an analogous procedure.
Quninone chemistry. Synthesis of 3‐dialkylsulfoximido‐ and 2‐dialkyl‐sulfimido‐3‐carbomethoxy‐1,4‐benzo‐ and naphthoquinone derivatives
Authors: Torres Tomás , Eswaran S. V. , Schäfer Wolfram
Published: April 2009

3‐Methoxy[2, 1]benzisoxazole‐4, 7‐quinones 1 and naphth[2,3‐c]isoxazole‐4,9‐quinone 4 react with dimethyl sulfoxides to give sulfoximidoquinones 2 and 5, sulfimidoquinones 8 and 11 respectively as major products.
Préparation de dithiényl‐2‐éthène‐1,2, de dithiényl‐2‐pyrimidine‐2,4 et de dithiényl‐2‐pyridazine‐3,6
Authors: Monthéard Jean‐Pierre , Dubois Jean‐Claude
Published: April 2009

La condensation du réactif de Grignard du bromo‐2‐thiophène avec les dérivés bihalogénés, tels que le di‐chloro‐1,2‐éthène (Z), la dichloro‐2,4‐pyrimidine et la dichloro‐3,6‐pyridazine, en présence de catalyseur à base de métal de transition permet d'obtenir, en une seule étape, des dérivés polycycliques, comportant deux noyaux thiophènes.
Antimykotische wirkstoffe. XIX. 4,6‐Disubstituierte 2‐(cyanamino)pyrimidine
Authors: Kreutzberger Alfred , Sellheim Michael
Published: April 2009

Aus der Umsetzung von Dicyandiamid (1) mit β‐Diketonen (2a‐c) gehen die 2‐Cyanaminopyrimidine (3a‐c) hervor. Strukturtyp 3 wird durch spektroskopische Daten gestützt, während gleichzeitig eine 1‐Cyan‐2‐imino‐struktur (4) ausgeschlossen wird. Verbindung 3a zeigt fungistatische und nematizide Wirkungen.
Synthesis of 2‐hydroxy‐2‐phenylethylamino derivatives as potential α‐adrenergic blocking agents
Authors: Alvarez M. , Granados R. , Lavilla R. , Salas M.
Published: April 2009

The synthesis of N,N'‐bis[6‐(2‐hydroxy‐2‐phenylethylamino)hexyl] cystamines 4, and N‐(2‐hydroxy‐2‐phenylethyl)‐1,6‐hexanediamines 6 are described. Compounds 4 were obtained by condensation of the requisite epoxide 2 with 3‐(6‐aminohexyl)‐1,3‐thiazolidine followed by dimerization with opening of the thiazolidine ring. A similar method was used for the preparation of compounds 6. In order to prepare 4j (N,N'‐bis{6‐[2‐hydroxy‐2(3,4‐dihydroxyphenyl)ethylamino]hexyl}cystamine), several procedures were tested; the method of choice involved the use of 3,4‐dihydroxybenzaldehyde with both hydroxy groups protected as methoxymethyl ethers.
Synthesis of thieno[2,3‐c:5,4‐c]dipyridine and the one electron transfer properties of its dimethyl diquaternary salt
Authors: Attalla Moetaz I. , Summers Lindsay A.
Published: April 2009

Thieno[2,3‐c:5,4‐c]dipyridine is synthesised by reaction of 3,3′‐thiobispyridine with sodium and liquid ammonia in dimethylformamide. It forms a diquaternary salt with excess methyl iodide. The salt is reversibly reduced to a stable blue‐green radical cation in aqueous solution at a potential (Eσ) of ‐0.38V.
The reaction of 5‐aminoimidazole‐4‐carbohydrazides with orthoesters
Authors: Bridson P. K. , Davis R. A. , Renner L. S.
Published: April 2009

The reaction of 5‐aminoimidazole‐4‐carbohydrazides with orthoesters is shown to yield 1‐amino‐9‐alkyl‐hypoxanthines. Similar reaction of anthranilic acid hydrazide is shown to yield 3‐amino‐4‐quinazolone, and not 1,4‐dihydro‐5H‐1,3,4‐benzotriazepin‐5‐one as previously reported.
Synthèse d'oxo‐2 pyranno[3,2‐c]benzopyrannes et d'oxo‐2 pyranno[3,2‐d]benzoxépines
Authors: Sacquet Marie‐Claude , Bellassoued‐Fargeau Marie‐Claude , Graffe Bernadette , Maitte Pierre
Published: April 2009

La condensation directe de chromanones‐4 ou de l'homochromanone‐5, en milieu basique, avec l'éthoxy‐méthylène malonate d'éthyle ou l'éthoxyméthylène malononitrile conduit à la formation d'un système α‐pyronique. Le rendement en carbéthoxy ou en carbamoyl pyrone varie en fonction de la position et de la nature des substituants sur les cétones de départ.
Covalent amination of 3,6‐dinitro‐1,8‐naphthyridines
Authors: Woźniak M. , Van Der Plas H. C. , Tomula M. , Van Veldhuizen A.
Published: April 2009

The preparation of 3,6‐dinitro‐2‐R‐1,8‐naphthyridines (1, R = OH, NH2, OC2H5, Cl) is described and their addition patterns with liquid ammonia are studied. Compound 1 (R = OH, NH2) gives with liquid ammonia at ‐ 45° as well as at room temperature formation of the covalent ó‐adduct 4‐amino‐1,4‐dihydro‐3,6‐dinitro‐2‐R‐1,8‐naphthyridine (2, R = OH, NH2). Compound 1 (R = OC2H5) yields with ammonia at ‐ 45° two σ‐adducts, i.e. the C‐4 adduct (2, R = OC2H5) and the C‐5 adduct 5‐amino‐5,8‐dihydro‐3,6‐dinitro‐2‐R‐1,8‐naphthyridine (3, R = OC2H5). The ratio is about 50:50. This ratio depends on the temperature; at room temperature the C‐5 adduct is more favoured. After staying overnight the ethoxy group has been exchanged for the amino group, yielding 2 (R = NH2). With 1 (R = Cl) both adducts 2 (R = CI) and 3 (R = CI) were formed, the C‐4 adduct 2 (R = CI) is more favoured at room temperature. Prolonged treatment with liquid ammonia leads to an exchange of the chloro atom by the amino group, yielding 2 (R = NH2).
Proton and carbon‐13 nuclear magnetic resonance spectroscopy and conformational aspects of 5,6,7,8‐tetrahydro‐4‐chromanone derivatives
Authors: Dolmazon René , Gelin Suzanne
Published: April 2009

The 25 MHz 13C and 350 MHz 1H‐nmr spectra of the title compounds are reported. Conformational equilibria in variously substituted 5,6,7,8‐tetrahydrochromanones are discussed. Compounds bearing a t‐butyl group at the 6 position appear to be conformationally homogenous.
Imino‐bridged heterocycles. IV . A facile synthesis of sulfenimines derived from diaryl ketones
Authors: Brenner Daniel G. , Cavolowsky Kathleen Mensler , Shepard Kenneth L.
Published: April 2009

Efficient, high‐yield syntheses of N‐diarylmethylene sulfenamides (sulfenimines) have been developed under mild laboratory conditions. Diaryl ketones have been shown to form ketimines readily by condensation with ammonia in the presence of titanium tetrachloride.
A novel synthesis of pyrido[2,3‐α]indolizine
Authors: Ross John R. , Sowell J. Walter
Published: April 2009

The synthesis of a new pyridoindolizine, in particular, pyrido[2,3‐α]indolizine, was carried out using 2‐methyl‐3‐t‐butoxycarbonyl‐4‐aminopyrrole as the starting material.
Studies on the synthesis and interconversion of isomeric triazolotheinopyrimidines. Part II. Effect of 5‐substituents on the dimroth rearrangement of 1,2,4‐triazolo[4,3‐c]thieno[3,2‐e]pyrimidines
Authors: Shishoo C. J. , Devani M. B. , Ullas G. V. , Ananthan S. , Bhadti V. S.
Published: April 2009

The triazolothienopyrimidines obtained by the cyclization of 4‐hydrazino‐2‐phenylthieno[2,3‐d]pyrimidines with triethyl orthoformate or formic acid presumed to be the triazolo[2,3‐c] isomers are now assigned the 5‐phenyl‐1,2,4‐triazolo[4,3‐c]thieno[3,2‐e]pyrimidine structure. While these [4,3‐c]triazoles resist isomerization under acidic conditions, they undergo isomerization to 5‐phenyl‐1,2,4‐triazolo[2,3‐e]thieno[3,2‐e]pyrimidines under basic conditions.
Spiro[(2,3‐dihydro‐2‐oxo‐imidazo[1,2‐a]pyridine)‐3,3‐(3,4‐dihydro‐2‐methyl‐4‐oxo‐2H‐1,2‐benzothiazine 1,1‐dioxide)]‐A novel product derived from piroxicam
Authors: Norris Charles P. , Berke Helen , Lombardino Joseph G. , Bordner Jon
Published: April 2009

A novel compound, spiro[(2,3‐dihydro‐2‐oxo‐imidazo[1,2‐a]pyridine)‐3,3‐(3,4‐dihydro‐2‐methyl‐4‐oxo‐2H‐1,2‐benzothiazine 1,1‐dioxide)] (3), was isolated during an attempt to convert 4‐hydroxy‐2‐methyl‐N‐(2‐pyridinyl)‐2H‐1,2‐benzothiazine‐3‐carboxamide 1,1‐dioxide (1) (Piroxicam) to an O‐trifluoromethanesulfonyl ester. A possible mechanism is offered to explain this unusual transformation.
Synthesis of 8‐substituted 5‐deazaflavins
Authors: Link P. A. J. , Van Der Pias H. C. , Müller F.
Published: April 2009

To obtain 5‐deazaflavins exhibiting red‐shifted light absorption spectra, a number of C(8) substituted 5‐deazaisoalloxazines were synthesized. This was accomplished a) by the oxidative cyclization of 5,5′‐arylmethylenebis(6‐methylaminouracil) derivatives and b) by the cyclization of N‐methylanilinouracil derivatives with a one‐carbon reagent. The latter method led to the formation of impure products. Condensation and oxidation reactions with the π‐electron deficient C(8) methyl group in 5‐deazalumiflavin did not occur. Introduction of substituents at the C(8) position caused a bathochromic shift that varied between 10 and 40 nm.
Studies on furan derivatives. X. Preparation of 2‐Methylfuro[2,3‐c]quinoline Derivatives
Authors: Usui Toshinao , Tsubone Yasuo , Tanaka Akira
Published: April 2009

4‐Chloro‐2‐methylfuro[2,3‐c]quinoline (IV) was synthesized from ethyl 3‐(2‐nitrophenyl)‐5‐methyl‐2‐furoate and IV was allowed to react with some nucleophiles to afford the corresponding 4‐substituted 2‐methylfuro‐[2,3‐c]quinoline derivatives, respectively. On treatment of IV with potassium azide in dimethylsulfoxide, 2‐methylfuro[2,3‐c]tetrazolo[1,5‐a]quinoline was formed path azido‐tetrazolo isomerization. 2‐Methylfuro‐[2,3‐c]quinoline was prepared by the reduction of IV.
Phosphorus pentoxide in organic synthesis. XX. Synthesis of N‐aryl‐7H‐pyrrolo[2,3‐d]pyrimidin‐4‐amines
Authors: Jørgensen Anker , El‐Bayouki Khairy A. M. , Pedersen Erik B.
Published: April 2009

N‐Aryl‐7H‐pyrrolo[2,3‐d]pyrimidine‐4‐amines 7 were prepared in 30‐67% yields by treating N7‐(1‐phenyl‐ethyl)pyrrolo[2,3‐d]pyrimidin‐4(3H)‐ones 2 with a mixture of phosphorus pentoxide, triethylamine hydrochloride, and an appropriate arylamine hydrochloride at 240° for 3‐7 hours.
The chemistry of polycyclic arene imine. VI. 1‐[N,N‐di‐(2‐propenyl)‐9‐phenanthreneamine‐10‐yl]‐1a,9b‐dihydrophenanthro[9,10‐b]azirine an unusual allylation product of phenanthrene 9,10‐imine
Authors: Weitzberg Moshe , Aizenshtat Zeev , Blum Jochanan
Published: April 2009

Phenanthrene 9,10‐imine (1) was shown to react with allyl bromide and 50% aqueous sodium hydroxide under phase transfer catalysis conditions to give the title compound 3 as the only product. The starting imine 1 is assumed to undergo initially bis alkylation to form an N,N‐di‐(2‐propenyl)phenanthrene 9,10‐iminium salt (4) which, in turn, is attacked by a deprotonated phenanthrene imine anion (5). The structure of 3 has been determined by a single crystal X‐ray diffraction analysis.
Potential anticonvulsants. X. (Reissert compounds studies. LI.) 1‐methyl‐4‐(1‐isoquinolinyl)piperidin‐4‐ol and related compounds
Authors: Popp Frank D. , Kant Joydeep
Published: April 2009

The anion of isoquinoline Reissert Compounds has been condensed with 4‐piperidones and pyridinecarb‐oxaldehydes to give esters which are easily hydrolyzed to alcohols. The anticonvulsants activity of these alcohols is reported and several are active in the maximal electroshock seizure test.
The reductive metalation of 9‐phenylacridine
Authors: Smith James G. , Fogg Deryn E.
Published: April 2009

The reductive metalation of 9‐phenylacridine by sodium to a dianion is described and the reactions of the dianion with electrophiles investigated. Reactions of the dianion with methanol, dimethyl sulfate, X(CH2)nX (n = 2,3,4, X = Cl, Br), and methyl chloroformate were studied. Reactions occurred exclusively at the 9 and 10 positions forming 9,10‐dihydro‐9‐phenylacridine derivatives. Of particular interest was the fact that the dianion was dialkylated with 1,2‐dichloroethane but monoalkylated at the 9‐position with 1,3‐dichloropropane and 1,4‐dichlorobutane. These results are compared to those obtained with dianions derived from other heterocyclic systems and analyzed using Baldwin's Rules for Ring Closure.
Mass spectrometry of modified nucleic acid bases and nucleosides. 2. Class II mesoionic nucleosides and bases derived from thiazolo[3,2‐a]pyrimidine‐5,7‐diones
Authors: Schubert Ernst M. , Schram Karl H. , Glennon Richard A.
Published: April 2009

The mass spectral characteristics of novel Class II mesoionic heterocyclic bases and nucleosides based on the thiazolo[3,2‐a]pyrimidine‐5,7‐dione system have been examined using low and high resolution mass spectrometry and metastable ion analysis. The mass spectra of these Class II mesoionic nucleosides differ significantly from the spectra of “normal” nucleosides by the absence of fragment ions associated with the base plus portions of the sugar. The difference in fragmentation is rationalized on the basis of exclusive localization of the radical‐charge site in the aglycone, a result of the mesoionic structure of these molecules. The fast atom bombardment (FAB) mass spectra of a Class I mesoionic nucleoside, 7‐methylguanosine, is compared to the FAB mass spectra of the Class II mesoionic nucleosides.
Dication ethers. 7. Dication ether salts from cyclic bisureas
Authors: Maas Gerhard , Brückmann Ralf , Feith Bernhard
Published: April 2009

The bicyclic bisureas 2 react with triflic anhydride to give the dication ether salts 4. Further transformation of the remaining carbonyl groups of 4 into bis‐carbenium ether linkages was not possible. The monocyclic bisurea 8 yields the dicationic heterocycle 9 in an intramolecular fashion. The structure of 9, which is the first dication ether salt with an endocyclic ether linkage, was established by independent synthesis from 10 as well as by its hydrolysis to give the hemi‐protonated bisurea 11.
Resolution and absolute configuration of 1,2,3,5,6,10bβ‐hexahydro‐6α‐phenylpyrrolo[2,1‐α]isoquinoline (McN‐4612‐Z). A problem of determination of the enantiomeric purity for a tertiary amine
Authors: Maryanoff Bruce E. , Mccomsey David F.
Published: April 2009

Details for the resolution of 1,2,3,5,6,10bβ‐hexahydro‐6α‐phenylpyrrolo[2,1‐α]isoquinoline(1), a potent antidepressant‐like compound, into its enantiomers with di‐p‐toluoyltartaric acid (2)are reported. Enantio‐merically‐enrichedR‐(+)‐2‐phenylpyrrolidine was transformed into enantiomerically‐enriched1to determine enantiomeric purity and absolute stereochemistry for the resolved amines1. Thus, we ascertain that samples of (+)‐ and (—)‐1with an enantiomeric purity of ≥99% were prepared, and that bioactive (+)‐1possesses the 6S,10bRabsolute configuration. The enantiomeric purity of ≥99% was confirmed by 360‐MHz1H nmr examination of 1:1 diastereomeric salts formed from1or (—)‐1and (+)‐Mosher's acid (MTPA). The maximal optical rotation reported (ref 8) for (+)‐3(100% o.p.) was shown to correspond to 100% e.e.
Photodegradation of a 1,3,4‐thiadiazole‐urea herbicide. Isolation, characterization, X‐ray crystal structure and synthesis of photoproducts
Authors: Moorman Allan R. , Findak David C. , Ku Han San
Published: April 2009

The photodegradation of 1,3‐dimethyl‐1‐(2‐(3‐fluorobenzylthio)‐1,3,4‐thiadiazol‐5‐yl)urea as a thin film and in solution is described. The two photoproducts from thin‐film photolysis were characterized by spectral and synthetic methods. The X‐ray crystal structure of one of the photoproducts is also reported. The rearrangements were shown to involve an S‐to‐N benzyl migration, followed by a sulfur‐oxygen substitution.
Conversion des furfurylalkyl et arylcetones en derives de l'isocoumarine et de l'isoquinoleine
Authors: Aicart Michel , Mavoungou‐Gomès Louis
Published: April 2009

Par catalyse acide, les produits de cycloaddition entre acétylenedicarboxylate de méthyle et furfurylalkyl ou arylcétones sont aromatisés en hydroxy‐6 phtalates de méthyle porteurs de groupements acétonyl ou phénacyl en position 3. Ces composés obtenus avec un rendement élevé constituent d'excellents intermédiates pour la préparation de dérivés polyfontionnels de l'isocoumarine et de l'isoquinoléine.
Synthesis of heterocyclic compounds using nitro ketene dithioacetal
Authors: Tominaga Yoshinori , Matsuda Yoshiro
Published: April 2009

This review describes developments in the synthesis of heterocyclic compounds using the nitro ketene dithioacetal 1‐nitro‐2,2‐bis(methylthio)ethylene (3).
Synthèse de l'amino‐3 azétidine
Authors: Nisato Dino , Frigerio Marco
Published: April 2009

La synthèse de l'amino‐3 azétidine (4), un bio‐équivalent potentiel de la pipérazine ou amino‐4 pipéridine, est decrite en utilisant une reaction catalysee par transfert de phase solide‐liquide.