bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of new pentacyclic diquinothiazines
Authors: Nowak Małgorzata , Pluta Krystian , Suwińska Kinga , Straver Leo 
Published: March 2009

Abstractmagnified imageReactions of 2,2′‐dichloro‐3,3′‐diquinolinyl sulfide 1 with ammonia derivatives and various primary alkylamines and arylamines proceeded as a thiazine ring closure to form linear annulated pentacyclic 6H‐diquinothiazine 2H and 6‐substituted derivatives 2 with alkyl, alkylaryl, aryl and heteroaryl substituents in moderate to good yields. Reaction with 2‐chloroethylamine did not stop at the formation of half‐mustard derivative 2k but ran to ethylenediquinothiazinium salt 11. 6H‐Diquinothiazine 2H was N‐alkylated and N‐arylated to give 6‐substituted derivatives 2. The crucial substrate 1 was obtained from other heteropentacenes 3 and 4 via 1,4‐dithiin ring opening and further transformations. X‐ray analysis of p‐nitrophenyldiquinothiazine 2i revealed unexpected planar thiazine ring.
2‐Vinyl quinazoline 3‐oxides; Preparation from acid induced cyclocondensation of 2‐acylaminoaryloximes
Authors: Heaney Frances , Lawless Elaine 
Published: March 2009

Abstractmagnified image2‐Vinyl quinazoline 3‐oxides 6a, 6b and 15a are useful modular building blocks for the construction of a range of heterocycles with potential biological activity, from o‐[amidoalkenyl]aryloximes 5a, 5b and 14a, respectively, by cyclocondensation. Conjugate addition of EtOH or MeOH to the vinyl moiety of 6b is demonstrated.
1,3‐dipolar cycloaddition reaction: Synthesis and configuration of norcantharidin derivatives of substituted aromatic amine
Authors: Deng Liping , Hu Yongzhou 
Published: March 2009

Abstractmagnified imageA series of eighteen novel compounds that have potential pharmacological properties has been synthesized by 1,3‐dipolar cycloaddition reactions of 5,6‐dehydronorcantharidin derivatives of substituted aromatic amine with nitrile oxide. The synthesis was carried out following straightforward three‐step procedure described herein. IR, 1H nmr and ms, H‐H cosy and Noesy Cyclonoe, confirmed the structure of all products respectively. The biological evaluation of three series of norcantharidin analogues against HL60 cell has been screened.
Synthesis and antimalarial activity of 7‐benzylamino‐1‐isoquinolinamines
Authors: Gutteridge Clare E. , Hoffman Marshall M. , Bhattacharjee Apurba K. , Gerena Lucia 
Published: March 2009

Abstractmagnified imageComputer modelling suggests that 7‐benzylamino‐1‐isoquinolinamines should mediate antimalarial effects by a mechanism distinct from that employed by existing antimalarial drugs. A series of these compounds was prepared in seven synthetic steps, via reductive amination of 1,7‐isoquinolinediamine. In vitro efficacy testing of the novel compounds against Plasmodium falciparum revealed them to be potent antimalarial agents.
Synthesis and antimalarial activity of ethyl 3‐amino‐4‐oxo‐9‐(phenylsubstituted)thieno[2,3‐b]quinoline‐2‐carboxylate derivatives
Authors: Charris Jaime , Barazarte Arthur , Domínguez JosÉ , Lobo Gricela , Camacho JosÉ , Ferrer Rosa , Gamboa Neira , Rodrigues Juan , Capparelli Mario V. 
Published: March 2009

Abstractmagnified imageA series of thieno[2,3‐b]quinolone derivatives were synthesized and investigated for their abilities to inhibit β‐hematin formation, hemoglobin hydrolysis and in vivo for their efficacy in rodent Plasmodium berghei. Compound 3b was the most promising as inhibitor of hemoglobin hydrolysis, and its effects as inhibitor of β‐hematin formation was promising. When the aromatic ring was substituted in 2 (Me), in 3 (CF3) or in 2,4 (Cl) the inhibition of hemoglobin proteolysis was maximal (88%), the rest of compounds maintained a low inhibition. The most active compound to emerge in vitro and in murine studies, was 3b suggesting an antimalarial activity via multiple mechanisms.
New isochromans. 1. Synthesis and antimicrobial activity of 4‐substituted (±)‐1h‐spiro[benzo[c]pyran‐3(4H), 1′‐cyclohexane]‐1‐ones
Authors: Bogdanov Milen G. , Palamareva Mariana D. , Gocheva Blagovesta T. , Dimitrova Darina B. 
Published: March 2009

Abstractmagnified imageThe reaction between homophthalic anhydride and cyclohexanone was examined both in the presence of DMAP or BF3·Et2O complex as a catalyst. The latter yielded (±)‐1‐oxo‐1H‐spiro[benzo[c]pyran‐3(4H), 1′‐cyclohexane]‐4‐carboxylic acid (3) in a higher yield (82 %). A series of new (±)‐4‐(N,N‐disubstituted‐1‐carbamoyl)‐1H‐spiro[benzo[c]pyran‐3(4H),1′‐cyclohexane]‐1‐ones (5a‐h) were synthesized from the parent acid 3 by a two‐step reaction. Differentiating microbial screening was performed for most of the synthesized compounds against twelve microorganisms belonging to different taxonomic groups. The spiro acid 3 was active against all bacterial strains with MIC ≥ 20 μg/ml against B. subtillis and P. vulgaris. E. coli was the most sensitive strain to the antibacterial effect of the tested compounds.
Synthesis, anti‐bacterial, anti‐asthmatic and anti‐diabetic activities of novel N‐substituted‐2‐(benzo[d]isoxazol‐3‐ylmethyl)‐1H‐benzimidazoles
Authors: Vaidya Sanjay Dashrath , Kumar Bobba Venkata Siva , Kumar Ramanatham Vinod , Bhise Umesh Nanasaheb , Mashelkar Uday Chandrakant 
Published: March 2009

Abstractmagnified imageSynthesis of a series of novel class of N‐substituted‐2‐(benzo[d]isoxazol‐3‐ylmethyl)‐1H‐benzimidazoles (4) by the condensation of o‐phenylenediamine (1) with benzo[d]isoxazol‐3‐yl‐acetic acid (2) and subsequent reactions with different types of electrophiles have been reported. Some compounds exhibited promising anti‐bacterial activity against Salmonella typhimurium, however poor activity against Staphylococcus aureus. The compound 4t was found to have high activity even at 1 μg/ml compared to Cephalexin against S. aureus. The biological activity against PDE‐IV for potential anti‐asthmatic effect and against DP‐IV and PTP‐1B for potential anti‐diabetic effects was disappointing.
A convenient one‐pot synthesis of new 3‐(4‐aryl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2‐yl)‐2H‐chromen‐2‐ones
Authors: Rajeswar Rao V. , Ravinder Reddy V. 
Published: March 2009

Abstractmagnified imageAnhydrous zinc bromide catalysed reactions of arylidine‐3‐acetyl coumarins (1a‐c) and 5,6‐benzoanalogs of arylidine 3‐acetyl coumarins (4a,4b) with 1,3‐cyclohexanedione gives ‐(4‐aryl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2yl)‐2H‐chromen‐2‐ones (3a, 3c) and 5,6‐benzoanalogs of 3‐(4‐aryl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2yl)‐2H‐chromen‐2‐one (5a,5b). Under similar conditions arylidine‐3‐acetylcoumarins (1a, 1b,1d, 1e, 1f) and 5,6‐benzoanalog of arylidine 3‐acetyl coumarin (4b) react with 5,5‐dimethyl‐1,3‐cyclohexanedione (dimedone) yielding 3‐(4‐aryl‐7,7‐dimethyl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2‐yl)‐2H‐chromen‐2‐ones (3d‐3h) and the 5,6‐benzoanalog of 3.(4‐aryl‐7,7‐dimethyl‐5‐oxo‐5,6,7,8‐tetrahydro‐4H‐chromen‐2‐yl)‐2H‐chromen‐2‐one (5c).
A facile one‐pot synthesis of 2‐amino‐4‐arylbenzo[h]quinoline‐3‐carbonitrile derivatives without catalyst
Authors: Tu Shujiang , Jia Runhong , Zhang Junyong , Zhang Yan , Jiang Bo 
Published: March 2009

Abstractmagnified imageA series of 2‐amino‐4‐arylbenzo[h]quinoline‐3‐carbonitrile derivatives were synthesized by one‐pot condensation of aromatic aldehyde, a‐naphthylamine and malononitrile in ethanol without catalyst. This multicomponent reaction has the notable advantages of short route, high yield and convenient operation.
Selective nucleophilic substitution reactions in 2,4,6‐trisulfanyl‐substituted pyrimidine‐5‐carbonitriles by secondary amines
Authors: Drescher Simon , Ramsbeck Daniel , Dobner Bodo , Briel Detlef 
Published: March 2009

Abstractmagnified imageThe highly functionalized heterocycles 6‐alkyl‐ respectively 6‐aralkylsulfanyl‐2,4‐bis‐(amidomethylsulfanyl) pyrimidine‐5‐carbonitriles react selective in the 2‐position with various secondary cyclic amines under mild conditions. The resulting pyrimidines were finally transformed into the corresponding thieno[2,3‐d]pyrimidine‐6‐carboxylic acid amides which afford the synthesis of selective substituted thienopyrimidines.
Three‐component, one‐pot synthesis of pyrimido[4,5‐b]‐quinoline and pyrido[2,3‐d]pyrimidine derivatives
Authors: Hassan N. A. , Hegab M. I. , Abdel‐Motti F. M. , Hebah S. H. A. , Abdel‐Megeid F. M. E. , Hashem A. I. 
Published: March 2009

Abstractmagnified imageReaction of 6‐amino‐2‐methylthiouracil and 6‐amino‐1,3‐dimethyluracil with equimoler amounts of cyclic ketones or cyclic 1,3‐diketones and the appropriate aromatic aldehydes yielded regioselectivity a series of polycyclic pyrimido[4,5‐b]quinoline and pyrido[2,3‐d]pyrimidine derivatives in good yields.
Dimethylformamide dimethyl acetal in heterocyclic synthesis: Synthesis of polyfunctionally substituted pyridine derivatives as precursors to bicycles and polycycles
Authors: Abu‐Shanab Fathi A. , Hessen A. M. , Mousa S. A. S. 
Published: March 2009

Abstractmagnified imagePolysubstituted pyridines 11a,c and 12 were prepared by the reaction of benzoylacetone with dimethylformamide dimethyl acetal followed by treatment with cyanothioacetamide 9a, cyanoacetamide 9b and the anion of malononitrile dimmer 9c in dry DMF. When the reaction was carried out in ethanol as a solvent and piperidine as a base afforded 14a,b. Thienopyridines 16a,b were prepared by the reaction of pyridinethiones 11a and 14a with 2‐chloro‐N‐p‐tolyl‐acetamide (15). Further reaction of thienopyridines 16a,b with either DMFDMA or nitrous acid to gave 17a,b and 18a,b respectively. The reaction of pyridine derivative 11c with hydrazine and phenylhydrazine afforded the tricyclic compounds 19a,b.
Microwave solvent free regioselective 1,3 dipolar cycloaddition in the synthesis of 1,4 substituted [1,2,3]‐triazoles as amide bond isosteres
Authors: Perissutti Elisa , Frecentese Francesco , Fiorino Ferdinando , Severino Beatrice , Cirillo Donatella , Santagada Vincenzo , Caliendo Giuseppe 
Published: March 2009

Abstractmagnified image1,3 Dipolar cycloaddition of Fmoc‐amino azides and acetylenic amides produces under solvent free irradiation a mixture of 1,4 or 1,5 substituted [1,2,3]‐triazoles. The presence of copper (I) iodide, plays a central role on regioselectivity. Four Fmoc‐amino azides characterized by different steric hindrance in side chains, and three different terminal alkynes, provided only the 1,4 substituted regioisomer under thermal microwave heating. Good yields, low consumption of organic solvents and short reaction times are the main aspects of our procedure. Reactions are compared to regioselective copper (I) catalysed solution synthesis performed at room temperature.
Synthesis of meso‐tetrakis(4‐chlorocoumarin‐3‐yl)porphyrins
Authors: Amaravathi M. , Rajitha B. , Rao M. Kanakalingeswara , Sitadevi P. 
Published: March 2009

Abstractmagnified imagemeso‐Tetrakis(4‐chlorocoumarin‐3‐yl)porphyrins were prepared by condensation of corresponding 4‐chlorocoumarin‐3‐carboxaldehydes and pyrrole in the presence of trifluoro acetic acid (TFA) in dichloromethane followed by oxidation with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ). These porphyrins exhibited the atropisomerism due to ortho substituent of meso aryl groups. The atropisomers of meso‐tetrakis(4‐chloro‐6‐methylcoumarin‐3‐yl)porphyrin were separated and identified by 1H‐nmr spectra. Zinc complexes of these porphyrins were synthesized and characterized by ms, 1H nmr, ir and uv‐vis spectra.
An efficient microwave‐assisted synthesis of 3,5‐unsubstituted 4‐substituted‐6‐aryl‐3,4‐dihydropyridin‐2(1H)‐ones derivatives
Authors: Tu Shujiang , Zhu Xiaotong , Shi Feng , Zhang Jinpeng , Zhang Yan 
Published: March 2009

Abstractmagnified imageSmall libraries of 3,5‐unsubstituted 4‐substituted‐6‐aryl‐3,4‐dihydropyridin‐2(1H)‐ones derivatives were synthesized from the condensation‐products of aldehydes with Meldrum's acid, aromatic ketones and ammonium acetate using acetic acid as energy transferring‐agent under microwave irradiation without catalyst. This method has the advantages of excellent yields (65‐90%), short reaction time (5‐10 min) and being environmentally friendly. It aimed to provide new series of potential biologically active compounds for biomedical screening.
Regioselective synthesis of pentacyclic polyheterocycles: Sequential [3,3] sigmatropic rearrangement of 4‐(4′‐aryloxybut‐2′‐ynyloxy)‐1‐phenyl‐1,8‐naphthyridin‐2(1H)‐ones
Authors: Majumdar Krishna C. , Rafique‐ul‐Islam  
Published: March 2009

Abstractmagnified imageA number of 4‐aryloxymethyl‐6‐phenyl‐2H‐pyrano[3,2‐c][1,8]naphthyridin‐5(6H)‐ones (4a‐f) are regioselectively synthesized in 72‐78% yield by the Claisen rearrangement of 4‐(4′‐aryloxybut‐2′‐ynyloxy)‐1‐phenyl‐1,8‐naphthyridin‐2(1H)‐ones (3a‐f) in refluxing chlorobenzene for 4‐6 h. These products are then subjected to a second Claisen rearrangement catalyzed by anhydrous AlCl3 at room temperature for 2 h to give hitherto unreported pentacyclic heterocycles (5a‐f) in 78‐85% yield.
Studies with pyridazines and condensed pyridazines: Routes for synthesis of 3‐amino‐5‐aryl‐2,5‐dihydro‐pyridazine, 10aH‐pyridazino[1,6‐a]quinazoline and thieno[3,4‐d]pyridazinone
Authors: Aziz Suzan Ibrahim , Anwar Hany Fakhry , El‐Apasery Morsy Ahmed , Elnagdi Mohamed Hilmy 
Published: March 2009

Abstractmagnified imageNovel routes to 3‐aminopyridazines, 10aH‐pyridazino[1,6‐a]quinazoline and, thieno[3,4‐d]pyridazine utilizing the reaction of 2‐oxobutanal‐1‐arylhydrazones 3a,b with α,β‐unsaturated nitriles are described. Condensation of 3 with ethyl cyanoacetate afforded pyridazinones that reacted with sulphur yielding thienopyradazinone 10. Reaction of 10 with maleic anhydride and acrylonitrile afforded products of addition and hydrogen sulphide elimination. On other hand reacting 10 with enaminone and ethyl propionate afforded the product of addition of the amino function to activated double bond.
Synthesis and biological properties of 1,8‐naphthalimidebutylamines. Serotonin 5‐HT1Aand 5‐HT7binding data and pass‐assisted search
Authors: Kowalski Piotr , Kowalska Teresa , Bojarski Andrzej J. , Duszyńska Beata 
Published: March 2009

Abstractmagnified imageSyntheses of the N‐substituted butyl derivatives of 1,8‐naphthalimide (1‐8), containing various arylpiperazines, tetrahydroisoquinoline and methylhomopiperazine moieties attached at 4‐position of the butyl chain have been described. Biological activities were evaluatedin vitrofor their ability to bind to serotonin 5‐HT1Aand 5‐HT7receptors. Due to the structural similarity of derivatives1‐8to psychotropic agents, the pharmacological properties of target compounds were predicted using PASS program.
A facile synthesis of 1‐alkyl‐5‐arylalkoxy‐6‐methoxy‐3,4‐dihydroisoquinolines
Authors: Yim Heong‐Seup , Kim Ho‐Kyun , Kim Jeum‐Jong , Kweon Deok‐Heon , Yoon Yong‐Jin , Lee Sang‐Gyeong , Kim Jung‐Ho 
Published: March 2009

Abstractmagnified image1‐Alkyl‐5‐arylalkoxy‐6‐methoxy‐3,4‐dihydroisoquinolines were synthesized by the alkylation of 1‐alkyl‐5‐hydroxy‐6‐methoxy‐3,4‐dihydroisoquinolines with arylalkyl halide in the presence of potassium carbonate. 1‐Alkyl‐5‐hydroxy‐6‐methoxy‐3,4‐dihydroisoquinolines as key precursor prepared from o‐vaniline via 6 steps.
Silica gel / NaHSO4: An efficient and recyclable heterogeneous catalyst for high yield synthesis of 1,5‐benzodiazepine derivatives under microwave irradiation
Authors: Chari M. Adharvana , Shobha D. , Syamasundar K. 
Published: March 2009

Abstractmagnified imageSilica gel supported sodium hydrogen sulfate catalyzes efficiently the condensation of o‐phenylenediamines with ketones under microwaves in solvent free conditions to afford the corresponding 1,5‐benzodiazepine derivatives in high yields. Compared to conventional reaction conditions, this new approach consistently has the advantage of excellent yields (90‐98%) and short reaction times of 0.50 – 1.00 min.
Regioselective cyclodehydration of ortho‐hydroxy acetyl aryloxyketones to benzofuran
Authors: Patel Jagdish M. , Soman Shubhangi S. 
Published: March 2009

Abstractmagnified imageortho‐Hydroxy acetyl benzofuran derivatives have been synthesized in a regioselective cyclodehydration of aryloxyketones obtained from β‐resacetophenone and α‐halo ketones.
Synthesis and photophysical properties of N‐styrylazinones
Authors: Cho Su‐Dong , Hwang Jaeyoung , Kim Ho‐Kyun , Yim Heung‐Sup , Kim Jeum‐Jong , Lee Sang‐Gyeong , Yoon Yong‐Jin 
Published: March 2009

Abstractmagnified imageN‐Styrylazinones and 1‐styrylbenzotriazine were synthesized, and their photophysical properties were investigated. (Z)‐ and/or (E)‐N‐Styrylazinones (or azine) 4 were prepared from the corresponding heterocycles 1 and benzaldehyde (3) by four methods. The absorption maxima of (Z)‐ and/or (E)‐4a‐4j were measured in four solvents. Their absorption maxima showed a moderate dependence upon solvents. The absorption maxima of (Z)‐isomers were blue‐shifted as compared the corresponding (E)‐isomers. Emission maxima, fluorescence band half‐widths, 0,0 transition energies, Stokes shifts, and quantum yields of (Z)‐ and/or (E)‐4a, 4b, 4d, 4e and 4j were measured in organic solvents. The fluorescence spectra show moderate solvatochroism. The fluorescence properties of N‐styrylheterocycles vary with every heterocycles.
BIFC and QFC promoted rapid and cleaner aromatization of 1,4‐dihydropyridines under solvent‐free condition
Authors: Sivamurugan Vajiravelu , Murugesan Velayutham , Suresh Valiyaveettil , Palanichamy Muthaiyahpillai , Vinu Ajayan 
Published: March 2009

Abstractmagnified imageThis communication expresses aromatisation of 1,4‐dihydropyridines to pyridine derivatives with the help of alumina supported benzimidazolium fluorochromate (BIFC) and quinolinium fluorochromate (QFC) as oxidants under solvent‐free microwave irradiation. Moderate to excellent yield (80‐98%) of pyridine derivatives were achieved by this methodology.
A facile three‐components, one‐pot synthesis of pyrimido[4,5‐d]pyrimidine‐2,5‐dione derivatives under microwave‐assisted conditions
Authors: Dabiri Minoo , Arvin‐Nezhad Hamid , Khavasi Hamid R. , Bazgir Ayoob 
Published: March 2009

Abstractmagnified imagePyrimido[4,5‐d]pyrimidine‐2,5‐dione derivatives have been synthesized in high yields in a novel, onepot, and efficient process by condensation of 6‐amino‐3‐methyl‐2‐(methylthio)pyrimidin‐4(3H)‐one, aldehydes and urea under microwave‐assisted conditions.
(±)‐2,3‐dialkyl‐1,2,3,4‐tetrahydroquinoline‐3‐carboxylic esters by a tandem reduction‐reductive amination reaction
Authors: Bunce Richard A. , Schammerhorn James E. , Slaughter LeGrande M. 
Published: March 2009

Abstractmagnified imageA series of 2‐methyl‐2‐(2‐nitrobenzyl)‐substituted β‐keto ester derivatives has been subjected to reductive cyclization under hydrogenation conditions to assess the importance of the ester group position on the diastereoselectivity of the process. Hydrogenation over 5% palladium‐on‐carbon at 4 atmospheres pressure resulted in formation of (±)‐2,3‐dialkyl‐1,2,3,4‐tetrahydroquinoline‐3‐carboxylic esters with a preference for the product isomer having the C2 alkyl cis to the C3 ester. The product ratios were synthetically useful (6‐16:1), but less than that observed in cyclizations to prepare (±)‐2‐alkyl‐1,2,3,4‐tetrahydroquinoline‐4‐carboxylic esters. The reduced selectivity in the current reactions has been rationalized in terms of the greater conformational mobility around the ester bearing carbon, which decreases the ability of the ester to sterically influence the addition of hydrogen to the final imine intermediate.
One‐pot synthesis of pyrido[2,3‐d]pyrimidines via efficient three‐component reaction in aqueous media
Authors: Shi Daqing , Ji Shunjun , Niu Lihui , Shi Jingwen , Wang Xiangshan 
Published: March 2009

Abstractmagnified imageA short and facile synthesis of pyrido[2,3‐d]pyrimidine derivatives was accomplished in good yieldsviathe three‐component reaction of aldehydes, alkyl nitriles and aminopyrimidines in water in the presence of triethylbenzylammonium chloride (TEBAC). The structures of these compounds were characterized by elemental analysis, IR and1H NMR spectra and further confirmed by single crystal X‐ray diffraction analysis.
A general and versatile synthesis of 3‐phenylthio β‐lactams as lead molecules for 3‐methyl‐2‐azetidinones
Authors: Kanwar Seema , Sharma S. D. 
Published: March 2009

Abstractmagnified imageKetene‐imine cycloaddition using phosphorus oxychloride and benzenesulfonyl chloride under the described reaction conditions yielded trans 3‐phenylthio 2‐azetidinones in good yields. Desulfurization using Raney nickel and alkylation finally afforded trans 3‐methyl‐2‐azetidinones in a stereoselective manner.
Synthesis of phenyl furyl sulfides and phenyl furyl ethers by nucleophilic substitution of nitrofurans
Authors: Ogawa Masayuki , Sakuma Katsuya , Okamoto Hiroshi , Koyanagi Jyunichi , Nakayama Kouji , Tanaka Akira , Yamamoto Katsumi 
Published: March 2009

Abstractmagnified imagePhenyl furyl sulfides (3a‐j) and phenyl furyl ethers (3k‐n), which are useful in synthesizing furocondensed 3‐ring compounds, can be synthesized by nucleophilic substitution of nitrofurans having electron withdrawal groups. In our experiments using 5‐nitrofurans having electron withdrawal groups (2a‐i), nucleophilic substitution readily occurred with the benzenethiolate anion of thiosalicylic acid (1a), the benzenethiolate anion of thiosalicylate ester (1b), and the phenylate anions of salicylate esters (1c‐d) to yield phenyl furyl sulfides (3a‐j) and phenyl furyl ethers (3k‐n).
Pyridazine and phthalazine derivatives with potential antimicrobial activity
Authors: Butnariu Roxana M. , Caprosu Maria D. , Bejan Vasilichia , Mangalagiu Ionel I. , Ungureanu Margareta , Poiata Antonia , Tuchilus Cristina , Florescu Margareta 
Published: March 2009

Abstractmagnified imageFifteen new pyridazine and phthalazine derivatives were prepared (in good to excellent yields) and tested in vitro as antimicrobial compounds. All the compounds have proved to have a remarkable activity against Gram positive germs, the results on Sarciria Luteea being spectacular. Correlation structure ‐ biological activity have been done. Stereo‐ and region‐ chemistry involved in these reactions are discussed.
Microwave assisted regiospecific synthesis of 5‐trifluoromethyl‐4,5‐dihydropyrazoles and—pyrazoles
Authors: Martins Marcos A. P. , Pereira Claudio M. P. , Moura Sidnei , Frizzo Clarissa P. , Beck Paulo , Zanatta Nilo , Bonacorso Helio G. , Flores Alex F. C. 
Published: March 2009

Abstractmagnified imageThe regiospecific synthesis of a series of twelve 5‐trifluoromethyl‐4,5‐dihydropyrazoles and ‐pyrazoles from the cyclocondesation reaction of 4‐alkoxy‐1,1,1‐trifluoro‐3‐alken‐2‐ones [F3CC(O)CH=C(R1)OR, where R1 = Me, Et, Pr, iso‐Pr, Bu, iso‐Bu, Ph, H; and R = Me, Et] with phenylhydrazine in toluene by environmentally benign microwave induced techniques is reported. It is shown that under appropriated conditions, the variation of microwave irradiation power leads to 4,5‐dihydropyrazole or pyrazole derivatives. This paper also includes the use of montmorillonite K‐10 as a solid support for the synthesis of pyrazoles under solvent free conditions.
The synthesis of some 3‐acylindoles revisited
Authors: Hasimbegovic Vedran , Slätt Johnny , Bergman Jan , Janosik Tomasz 
Published: March 2009

Abstractmagnified imageA study probing the scope of acylation of indoles with dicarboxylic acids in acetic anhydride has been performed, resulting in products incorporating 3‐acylindole‐ or 1‐acylindole motifs depending on the choice of the acid reactant. Synthetically useful results were only obtained from reactions involving malonic acid or Meldrum's acid. Correlations to previous studies have also been made and discussed.