bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and central nervous system stimulant activity of 5,8‐methanoquinazolines fused with imidazole, thiadiazole, pyrimidine and 1,3,5‐triazine
Authors: Nagai Sbin‐Ichi , Ueda Taisei , Nagatsu Akito , Nakaoka Keiko , Murakami Nobutoshi , Sakakibara Jinsaku , Fujita Michiko , Hotta Yoshihiro 
Published: March 2009

Abstract5,8‐Methanoquinazolines fused with imidazoles 4a‐4b, thiadiazoles 5–6, pyrimidines 7, 9, 11 and 12, and 1,3,5‐triazine 13 were prepared starting from (5R,8S)‐2‐amino‐8,9,9‐trimethyl‐5,6,7,8‐tetrahydro‐5,8‐methanoquinazoline 3. Most compounds possessed central nervous system stimulant activities.
Novel solid‐state synthesis of dimeric 4‐aryl‐1,4‐dihydropyridines
Authors: Hilgeroth Andreas , Heinemann Frank W. 
Published: March 2009

AbstractOn irradiation in the solid state the 4‐aryl‐1,4‐dihydroypridines 1 undergo [2+2] cycloadditon to centrosymmetric head‐to‐tail dimers 3 and 4a. The almost exclusive formation of the cage dimers 3 via the C2‐symmetric syn‐dimers 2 takes place in nearly quantitative yields, in contrast with the cycloaddition reaction of the anti‐dimer 4a, which is accompanied by photooxidation to pyridine 5a.
A study on ester formylhydrazones
Authors: Ikizler Aykut A. , Yildirim Nuri 
Published: March 2009

AbstractA series of ester formylhydrazones 2 were synthesized from the reaction of alkyl imidate hydrochlorides 1 with formylhydrazine. Treatment of 2 with hydrazine hydrate, ethyl carbazate and tert‐butyl carbazate led to the formation of 3‐alkyl‐4‐amino‐, 3‐alkyl‐4‐ethoxycarbonylamino‐ and 3‐alkyl‐4‐tert‐butoxycar‐bonylamino‐4H‐1,2,4‐triazoles 3–5, respectively. Reaction of compounds 2 with formylhydrazine gave N,N'‐diformylhydrazine 6. Compounds 2 were reacted with 2,5‐dimethoxytetrahydrofuran to afford 3‐alkyl‐4‐(1H‐pyrrol‐1‐yl)‐4H‐1,2,4‐triazoles 8.
Synthesis of spiro[2H‐indole‐2,1′‐1H‐isoindole]‐3,3′‐diones, spiro[1H‐isobenzofuran‐1,2′‐2H‐indole]‐3,3′‐diones and spiro[benzofuran‐2,1′‐isobenzofuran]‐3,3′‐diones via transannular reactions of eight membered ring intermediates
Authors: Bullington James L. , Dodd John H. 
Published: March 2009

AbstractAn auto oxidation‐rearrangement product 4 was isolated from a high dilution reaction of ninhydrin with 3,4,5‐trimethoxyaniline in water. A general synthesis of this compound and its derivatives 4–6 was devised by oxidation of tetrahydroindeno[1,2‐b]indol‐10‐ones 1–3 with sodium periodate to give isoindolo[2,1‐a]‐indole‐6,11‐diones 4–6 in good yield. Compounds 4–6 can be easily transformed into spiro[1H‐isobenzofuran‐1,2′‐2H‐indole]‐3,3′‐diones 8–10, spiro[2H‐indole‐2,1′‐1H‐isoindole]‐3,3′‐diones 11–13 and isoindole[1,2‐a:2′,1′‐b]pyrimidine‐5,15‐diones 15, 16 in high yields. Analogous reactions were performed on 3‐amino‐5a, 10a‐dihydroxybenzo[b]indeno[2,1‐d]furan‐10‐one (17) to give a dibenzoxocintrione 18, spiro‐[benzofuran‐2,1′‐isobenzofuran]‐3,3′‐dione 19 and an isoindol‐1‐one 20.
Haloacetylated enol ethers. 9. Synthesis of 4‐trifluoromethyl‐2‐methyl[phenyl]pyrimidines and tetrahydro derivatives
Authors: Zanatta Nilo , Fagundes Madelon B. , Ellensohn Ricardo , Marques Marcelo , Bonacorso Helio G. , Martins Marcos A. P. 
Published: March 2009

AbstractThe synthesis of 4‐trifluoromethyl‐2‐methyl[phenyl]pyrimidines and the corresponding tetrahydro derivatives from the cyclo‐condensation reaction of β‐alkoxyvinyl trifluoromethyl ketones 1a‐d with acetamidine or benzamidine hydrochloride, is reported. For the cyclo‐condensation of 1a‐d with acetamidine and benzamidine hydrochloride, two methods were tested: 1 M solution of sodium hydroxide (method A) and sodium alkoxide/alcohol (method B). Depending on the structure of the β‐alkoxyvinyl trifluoromethyl ketones and the reactions conditions, pyrimidines or tetrahydropyrimidines or a mixture of both compounds were obtained.
Synthesis and debenzoylation products of two perbenzoylated 2‐substituted 5‐D‐galactosyl‐1,3,4‐oxadiazoles
Authors: Cannizzaro Carina E. , Thiel Inge M. E. , D'Accorso Norma B. 
Published: March 2009

AbstractThe synthesis of 2‐(p‐chlorophenyl)‐5‐[1′,2′,3′,4′,5′‐penta‐O‐benzoyl‐D‐galactopentitol‐1‐yl]‐1,3,4‐oxadiazole is described. Its debenzoylation gave an equilibrium mixture of the 1,3,4‐oxadiazole derivative without protection of the hydroxyl group and the N‐benzoyl‐D‐galactono‐1,4‐lactonehydrazone. A similar equilibrium was observed by debenzoylation of 2‐phenyl‐5‐[1′,2′,3′,4′,5′‐penta‐O‐benzoyl‐D‐galactopentitol‐1‐yl]‐1,3,4‐oxadiazole. The 1H, 13C nmr and ms spectra of these compounds are presented.
Synthesis of new 6‐(4‐chlorophenyl)perhydro‐1,3‐diazepine‐2,4‐diones via ureidobutyric acids
Authors: Guillon Jean , Sonnet Pascal , Dallemagne Patrick , Miel Hugues , Rault Sylvain , Daoust Martine , Boulouard Michel 
Published: March 2009

AbstractSynthesis of new 6‐(4‐chlorophenyl)perhydro‐1,3‐diazepine‐2,4‐diones was accomplished starting from 4‐amino‐3‐(4‐chlorophenyl)butyric acid (Baclofen). The chemical pathway involved the cyclisation of various 3‐(4‐chlorophenyl)‐4‐ureidobutyric acids. However, none of the new derivatives retained the anticonvulsant activity of their six‐membered ring homologues, belonging to the phenylpyrimidinedione series which we recently described.
Syntheses of new pyridonecarboxylic acid derivatives containing 3‐,5‐ or 6‐quinolyl substituents at N‐1 and their anti‐HIV‐RT activities
Authors: Oh Yoon‐Seok , Lee Chi‐Wbo , Chung Yong‐Ho , Yoon Sung‐June , Cho Sung‐ Hye 
Published: March 2009

AbstractA series of new pyridonecarboxylic acid derivatives containing 3‐, 5‐ or 6‐quinolyl substituents at N‐1 were synthesized and their in vitro anti‐HIV‐RT activities were evaluated. Several compounds in this series showed better activity than Atevirdine.
Studies on pyrrolidinones. Synthesis of N‐benzhydrylpyroglutamic acids and esters
Authors: Rigo Benoît , Gautret Philippe , Legrand Anne , Hénichart Jean Pierre , Couturier Daniel 
Published: March 2009

AbstractCatalyzed N‐alkylation of N,O‐bistrimethylsilyl pyroglutamic acid with trimethylsilyl benzhydryl ethers yields trimethylsilyl N‐benzhydrylpyroglutamates. Hydrolysis of these compounds or saponification of the methyl esters gives the corresponding acids.
Ring opening reactions of 6‐oxo‐substituted spiro‐pyrrolidinediones: Synthesis of 4‐substituted‐1,5‐dihydro‐3‐hydroxy‐2‐oxo‐1,5‐diphenyl‐2H‐pyrroles
Authors: Emerson David W. , Titus Richard L. , Jones Marlon D. 
Published: March 2009

AbstractReaction of 2‐oxocylalkaneglyoxylate esters with N‐phenylmethyleneaniline yields spiro compounds such as 2‐aza‐3,4,6,‐trioxo‐1,2‐diphenylspiro[4.4]nonane 4 and cycloalkane‐2‐aza‐3,4,6‐trioxo‐1,2‐diphenylspiro‐[4.5]decanes 5–7. These undergo solvolytic opening of the the oxocycloalkane ring to yield 4‐substituted‐1,5‐dihydro‐3‐hydroxy‐2‐oxo‐1,5‐diphenyl‐2H‐pyrroles 12–17.
Cycloadditions of isoquinolinium N‐arylimides to enamines
Authors: Huisgen Rolf , Durst Tony , Temme Robert 
Published: March 2009

AbstractThe azomethine imine group of isoquinolinium N‐arylimides 2 is partially incorporated into an aromatic ring. The nucleophilic‐electrophilic 1,3‐dipoles 2 undergo cycloadditions to ethylene derivatives bearing either electron‐withdrawing or electron‐releasing substituents. The regiochemistry is bidirectional; electron‐attracting substituents appear at the 1‐position of the tricyclic adducts. Various enamines, however, adopt an orientation such that the amino function appears at the 2‐position. The tricyclic adducts undergo an acid‐catalyzed hyrazo rearrangement.
[4+2] Cycloaddition of 2(1H)‐pyrazinones and 1,2,4‐triazoline‐3,5‐diones
Authors: Nishio Takehiko 
Published: March 2009

AbstractThe reaction of 2(1H)‐pyrazinones 1 and 1,2,4‐triazoline‐3,5‐diones 3 was investigated by comparing that of 1 with singlet oxygen. 2(1H)‐Pyrazinones 1 reacted in Diels‐Alder fashion with 1,2,4‐triazoline‐3,5‐diones 3 to afford [4+2]‐adducts 4–17 in high yields.
General synthetic route to benz[g]isoquinolines (2‐azaanthracenes)
Authors: Krapcho A. Paul , Gilmor Timothy P. 
Published: March 2009

AbstractBenzylic zinc reagents add with high regioselectivity to 1‐(phenoxycarbonyl) salts derived from pyridine‐3‐carboxaldehyde (1a) or 3‐acetylpyridine (1b) to yield 1‐(phenoxylcarbonyl)‐4‐benzyl‐1,4‐dihydropyridine‐3‐carboxaldehydes 5a, 5c or ketones 5b, 5d. Aromatizations of these dihydro analogues with sulfur led to the corresponding aldehydes 6a, 6c or ketones 6b, 6d. An alternate synthesis to the aldehydic precursors involved additions of benzylic zinc reagents to 1‐(phenoxycarbonyl) salts formed from methyl nicotinates which led to the corresponding methyl 1‐(phenoxycarbonyl)‐4‐benzyl‐1,4‐dihydronicotinates 7a, 7b. Aromatizations of 7a, 7b led to the corresponding pyridine esters 8a, 8b which on reduction with lithium aluminum hydride yielded the corresponding carbinols 9a, 9b. Oxidation of 9a, 9b by manganese dioxide afforded aldehydes 6e, 6f. Aldehydes 6a‐f were readily converted into the benz[g]isoquinolines 10a‐f on heating in polyphosphoric acid.
Preparation of fluorinated phenoxathiin dioxide monoamine oxidase‐A inhibitors: Intramolecular radical substitution at sulfur versus the mauthner synthesis
Authors: Boros Eric E. , Hall William R. , Harfenist Morton , Kelley James L. , Reeves Mark D. , Styles Virgil L. 
Published: March 2009

AbstractFive unique fluorinated analogs, 8a‐c and 15a,b, of the monoamine oxidase‐A inhibitor 3‐iso‐propoxyphenoxathiin 10,10‐dioxide (II) were prepared via oxidation of the corresponding phenoxathiins 7 and 14. 3‐Fluoro‐7‐isopropoxy‐ 7a, 2‐fluoro‐3‐isopropoxy‐ 7b, and 2,7‐difluoro‐3‐isopropoxyphenoxathiin (7c) were prepared by a modification of the Mauthner synthesis which involved cyclization of the corresponding 2‐hydroxy‐4‐isopropoxythiophenols 4 with the appropriate 2‐halonitrobenzenes 5 in the presence of potassium tert‐butoxide. Preparation of 2,8‐difluoro‐3‐isopropoxyphenoxathiin (14b) from 4b and 2,4‐difluoronitrobenzene (5c) employing similar methods failed, leading instead to a novel macrocycle 9. Attempts to obtain 2‐fluoro‐7‐isopropoxyphenoxathün (14a) and the 2,8‐difluoro analog 14b via trifluoroacetic acid deprotection of intermediate thio‐protected 2‐nitrophenyl 2‐thiophenyl ethers 11a and c followed by cyclization of the resulting thiols were also unsuccessful. Deprotection of 11a with trifluoroacetic acid produced only complex product mixtures, while similar deprotection of 11c and treatment of the resulting crude product with potassium tert‐butoxide in refluxing dimethylformamide produced the 2,7‐difluorophenoxathiin analog 7c, a result consistent with a Smiles rearrangement of the intermediate thiol 12 prior to ring closure. The phenoxathiins 14 were ultimately prepared by a modification of a relatively unexploited phenoxathiin synthesis involving the intramolecular radical substitution at sulfur of 2‐aminophenyl 2‐thiophenyl ethers 13 containing para‐methoxybenzyl and methoxymethylthio‐protecting groups.
Synthesis of bilin‐1,19‐diones and biladiene‐ac‐1,19‐diones with c(10) adamantyl and tert‐butyl groups
Authors: Kar Ari K. , Lightner David A. 
Published: March 2009

AbstractBilirubin and biliverdin analogs bearing bulky adamantyl and tert‐butyl groups at the central C(10) position were synthesized and their structures were analyzed by nmr and ultraviolet‐visible spectroscopy and by molecular mechanics calculations, all of which collectively indicated a preference for helical conformations.
A new expedient route to 2,6‐diaryl‐3‐cyano‐4‐(trifluoromethyl)pyridines
Authors: Yamaguchi Yoshihiro , Katsuyama Isamu , Funabiki Kazumasa , Matsui Masaki , Shibata Katsuyoshi 
Published: March 2009

Abstract1‐Aryl‐4,4,4‐trifluoro‐1,3‐butanediones 1 react with β‐amino‐β‐arylacrylonitrile 2, readily available from acetonitrile with aryl nitriles in the presence of potassium t‐butoxide, to afford the corresponding 2,6‐diaryl‐3‐cyano‐4‐(trifluoromethyl)pyridines 3 in moderate to excellent yields.
Reaction of metallo S‐alkyl N‐cyanodithioiminocarbonates and alkyl N‐cyanocarbamates with hydrazine. A novel preparation of 5‐amino‐3‐mercapto‐1,2,4‐triazole
Authors: Marble Lyndon K. , Puckett Wallace E. , Summers William Russell 
Published: March 2009

AbstractMetal salts of S‐alkyl‐N‐cyanodithioiminocarbonates 7 react as electrophiles with hydrazine hydrate to form 5‐amino‐3‐mercapto‐1H‐1,2,4‐triazole 1. The novel 4‐cyanothiosemicarbazide 9 is proposed as the intermediate which cyclizes to the aromatic triazole. The rate determining step is addition of hydrazine to the iminocarbonate and is second order. Other nucleophiles such as substituted hydrazines and amines failed to react. Exchange of either or both sulfurs with oxygen leads to decomposition or mixtures of products.
Synthesis and cyclization reactions of 2‐amino‐3‐[(methoxy‐carbonyl)methylsulfonyl]pyrroles and thiophene
Authors: Stephens Chad E. , Sowell J. Walter 
Published: March 2009

AbstractThe title aminopyrroles and thiophene have been prepared by condensation of methyl (cyanomethyl‐sulfonyl)acetate with various α‐amino ketones or 2‐mercaptoacetaldehyde, respectively. Subsequent cyclization of these compounds by reaction between the amine and activated methylene has led to various ester‐substituted thiazine‐ and thiadiazine‐based bicyclic derivatives. In addition, cyclization of the title compounds by intramolecular coupling of the amine and ester has led to the analogous bicyclic thiazin‐3(2H)‐ones. Attempted hydrolysis of the ester‐substituted bicyclics to the corresponding carboxylic acids was unsuccessful.
Synthesis of polycyclic pyridazinediones as chemiluminescent compounds
Authors: Tominaga Yoshinori , Sasaki Kenji , Castle Raymond N. 
Published: March 2009

AbstractReactions of 1,3‐disubstituted 5‐aminopyrazole‐4‐carbonitrile derivatives 3a‐o with dimethyl acetylenedicarboxylate in the presence of potassium carbonate in dimethyl sulfoxide gave the corresponding dimethyl 1,3‐disubstituted pyrazolo[3,4‐b]pyridine‐5,6‐dicarboxylates 4a‐o which were allowed to react with excess hydrazine hydrate under ethanol refluxing conditions followed by heating at 250‐300° to give 1,3‐disubstituted 4‐amino‐1H‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyridazine‐5,8(6H,7H)‐diones 7a‐s in good yields. Similarly, 1,3‐disubstituted 4‐hydroxy‐1H‐pyrazolo[4′3′:5,6]pyrido[2,3‐d]pyridazine‐5,8(6H,7H)‐diones 10a‐c were obtained from alkyl 1,3‐disubstituted 5‐aminopyrazole‐4‐carboxylates 8a‐c. These tricyclic pyridazine derivatives were alternatively synthesized from 4‐hydroxypyrrolo[3,4‐e]pyrazolo[3,4‐b]pyridine‐5,7‐diones 13a‐c prepared by reactions of 5‐aminopyrazoles (8e‐g) with methyl 1‐methyl‐4‐methylthio‐2,5‐dioxo‐1H‐pyrrole‐3‐carboxylate (11a) followed by the Gould/Jacobs reaction.1‐Methyl‐4‐methylthio‐2,5‐dioxo‐1H‐pyrrole‐3‐carbonitrile smoothly reacted with 2‐aminobenzimidazoles to give the corresponding 5‐amino‐3‐methyl‐1H‐pyrrolo[3′4′:4,5]pyrimido[1,2‐a]benzimidazole‐1,3(2H)‐diones 16a‐e, which were readily converted to the desired 12‐aminopyridazino[4′,5′:4,5]pyrimido‐[1,2‐a]benzimidazole‐1,4(2H,3H)‐diones 17a‐e in good yields. Other pyridazinopyrimidine derivatives were also obtained by the reaction of the corresponding 2‐aminoheterocycles with the maleimide in good yields.Substituted anilines reacted 11b in refluxing methanol to give the corresponding methyl 4‐phenylamino‐1‐methyl‐2,5‐dioxo‐1H‐pyrrole‐3‐carboxylates 25a‐e which were converted in good yields to 2‐methylpyrrolo[3,4‐b]quinoline derivatives 26a‐e by heating in diphenyl ether. Reaction of 26a‐c with hydrazine hydrate gave 10‐hydroxypyridazino[4,5‐b]quinoline‐1,4(2H,3H)‐diones 27a‐e in good yields. The desired 10‐aminopyridazino[4,5‐b]pyridazine‐1,4(2H,3H)‐diones 30a‐e were obtained in good yields by the chlorination of 4a‐e with phosphorus oxychloride followed by aminolysis with 28% ammonium hydroxide.Some pyridazino[4,5‐a][2.2.3]cyclazine‐1,4(2H,3H)‐diones 37a,b as luminescent compounds were synthesized via several steps from indolizine derivatives. The key intermediates, dimethyl 6‐dimethylamino[2.2.3]cyclazine‐1,2‐dicarboxylates 34, 36, were synthesized by the [8 + 2] cycloaddition reaction of the corresponding 7‐dimethylaminoindolizines 33, 35 with dimethyl acetylenedicarboxylate in the presence of Pd‐C in refluxing toluene.Some were found to be more efficient than luminol in light production. 4‐Amino‐3‐methylsufonyl‐1‐phenyl‐1H‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyridazine‐5,8(6H,7H)‐dione (7r), 10‐hydroxypyridazino[4,5‐b]‐quinoline‐1,4(2H,3H)‐diones 27a‐e, and 10‐aminopyridazino[4,5‐b]quinoline‐1,4(2H,3H)‐diones 30a‐e showed the greatest chemiluminescence intensity in the presence of hydrogen peroxide peroxidase in a solution of phosphate buffer at pH 8.0.
The trapping of j,x‐biradicals, photochemically produced, with 4‐cyanopyridine in neutral and acidic medium
Authors: Bernardi Rosanna , Caronna Tullio , Mele Andrea , Morrocchi Sergio , Ursini Maurizio 
Published: March 2009

Abstract4‐Cyanopyridine is able to trap 1,x‐biradicals produced by direct photochemical excitation of some ketones, showing in some cases that unaspected species are formed and pyridine producs which are not explainable on the basis of actual knowledge.
Synthesis of substituted 10,11‐dihydro‐5H‐dibenz[b,f]azepines; key synthons in syntheses of pharmaceutically active compounds
Authors: Jørgensen Tine Krogh , Andersen Knud Erik , Lau Jesper , Madsen Peter , Huusfeldt Per Olaf 
Published: March 2009

AbstractSubstituted 10,11‐dihydro‐5H‐dibenz[b,f]azepines are key synthons in the syntheses of a number of pharmaceutically active compounds such as imipramine, chlorimipramine, and desimipramine analogues. A facile synthesis of substituted 10,11‐dihydro‐5H‐dibenz[b,f]azepines is described, starting out from com mercially available 2‐bromotoluenes or 2‐nitrotoluenes. Initial α‐bromination with N‐bromosuccinimide and subsequent reaction with triethylphosphite afforded the corresponding benzyl phosphonic ester deriva tives. After reaction with benzaldehyde derivatives, the expected Horner‐Emmons reaction products were obtained. Hydrogenation gave the amino derivatives which were transformed into the corresponding formamides. Under Goldberg conditions [1], the final ring closing step was performed to give the substituted 10,11‐dihydro‐5H‐dibenz[b,f]azepines in 46–75% yield.
Synthesis and properties of 1‐aryl‐2‐alkyl‐1,4,5,6‐tetrahydropyrimidines
Authors: Orelli Liliana R. , Niemevz Fernando , García María B. , Perillo Isabel A. 
Published: March 2009

AbstractA general method is described for the synthesis of 1‐aryl‐2‐alkyl‐1,4,5,6‐tetrahydropyrimidines 1, by cyclization of N‐acyl‐N′‐aryltrimethylenediamines 2 with trimethylsilyl polyphosphate. Precursors 2 were obtained by aminolysis of the corresponding N‐(3‐bromopropyl)amides 3. The 1H nmr spectra of tetrahydropyrimidines 1 are analyzed, discussing the influence of substituents in positions 1 and 2 of the heterocyclic ring. Alkaline hydrolysis of compounds 1, which originates exclusively N‐acyl‐N′‐aryltrimethylenediamines 2, through an intermediate carbinolamine, was also studied. Cleavage of such an intermediate is discussed in the light of the stereoelectronic control theory. Reduction of compounds 1 with borane, leads regiospecifically to N‐alkyl‐N′‐aryltrimethylenediamines 6.
Reactions of 2,3‐dihydrospiro[1H‐4‐ and 5‐azabenzimidazole‐2,1′‐cyclohexane] with nucleophiles: A potential route to some substituted aromatic heterocycles
Authors: Reizner Ralf , Kramer Walter , Neidlein Richard , Suschitzky Hans 
Published: March 2009

AbstractThe readily available title compounds 2, 16 and 27 react with pseudohalogenes (cyanide, azide), carbon and heterocyclic N‐nucleophiles in the presence of manganese dioxide to give the corresponding substituted azaisobenzimidazoles (= 2H‐azabenzimidazoles) 4, 8, 23–26 and 29–33, 36 or dihydroazabenzimidazoles (= 2,3‐dihydro‐1H‐azabenzimidazoles 7, 22, 34 and 35. In 8 one of the two imidazolyl‐substituents can be replaced by nucleophiles yielding the compounds 9–15. Treatment of 6′‐bromo‐2,3‐dihydro‐4‐azabenzimidazole 16 with morpholine or piperidine results in loss of the Br‐atom presumably by an AEa‐mechanism. Reduction of the substituted azaisobenzimidazoles with sodium hydrosulfite followed by fission of the cyclohexane ring leads to substituted o‐diaminopyridines. They were cyclised in situ with various condens ing agents to give new heterocyclic systems. Equimolar mixtures of some azaisobenzimidazoles and dihydroazabenzimidazoles lead to the formation of coloured charge transfer complexes stable only in the solid state. Owing to poor electron‐acceptor properties the complex dissociates in solution.
Acylation, cyanoethylation and alkylation of methyl and phenyl indolylmagnesium salts: Influence of the substituents on the c‐ and N‐reaction products
Authors: Rodríguez J. Gonzalo , Urrutia Anahí 
Published: March 2009

AbstractAnalysis of the influence of the substitution on indolylmagnesium salts in the reaction with benzoyl chlo ride, acrylonitrile and methyl iodide, giving the C‐ and N‐derivatives, have been carried out. The yield in the C‐ and N‐product depends upon the electronic character and position of the substituent (methyl or phenyl) on the indole ring and of the ethereal solvent as well as the concentration and molar ratio of the reagents. The 2‐ or 3‐phenyl substituted indolylmagnesium salts with acrylonitrile always gave the 1‐(2‐cyanoethyl)indole derivative.
Semi‐empirical evaluation of substituted terthiophenes as polythiophene precursors
Authors: Stanforth Stephen P. 
Published: March 2009

AbstractPM3 Semi‐empirical molecular orbital calculations have been performed on terthiophene derivatives which are also heteropentalene mesomeric betaines. The ionization potentials and band‐gaps have been determined in order to identify systems which might provide suitable monomers for conducting polythio phene derivatives.
Inhibitors of dihydrofolate reductase: Design, synthesis and antimicrobial activities of 2,4‐diamino‐6‐methyl‐5‐ethynylpyrimidines
Authors: Jones Michael L. , Baccanari David P. , Tansik Robert L. , Boytos Christine M. , Rudolph Sharon K. , Kuyper Lee F. 
Published: March 2009

AbstractNovel 2,4‐diamino‐6‐methyl‐5‐ethynylpyrimidines were prepared via palladium catalyzed coupling of 2,4‐diamino‐5‐iodo‐6‐methyl‐pyrimidine with terminal acetylenes. The compounds were inhibitors of dihydrofolate reductase and showed in vitro activity against several species of opportunistic fungi and the protozoan Toxoplasma gondii.
Synthesis and reactions of 4H‐3,1‐benzothiazines
Authors: El‐Desoky S. I. , Kandeel E. M. , Abd‐El‐Rahman A. H. , Schmidt R. R. 
Published: March 2009

AbstractThis study is directed towards the synthesis of the pyrrolo[1,2‐α]indole skeleton which is the essential ring system of the active antitumor miomycins. To this end a number of fused heterocycles such as benzothiazines, benzoxazines, indoles and quinolines were synthesized. The structures of the new compounds were assigned by ir, 1H nmr and ms‐data.
Synthesis and absolute configuration of (‐)‐meridinol and (‐)‐3‐epimeridinol
Authors: Takano Daisuke , Doe Matsumi , Morimoto Yoshiki , Kinoshita Takamasa , Yoshihara Kazuo 
Published: March 2009

AbstractThe first synthesis of (‐)‐meridinol and (‐)‐3‐epimeridinol was accomplished from (S)‐malic acid. This synthesis unambiguously established the absolute stereochemistry of meridinol.