bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis, stereochemistry and adsorption studies of new spiranes and polyspiranes containing 1,2‐dithiolane units
Authors: Gropeanu Radu A. , Ţînţaş Mihaela L. , Pilon Catherine , Morin Mario , Breau Livain , Turdean Raluca , Grosu Ion
Published: March 2009

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The synthesis and stereochemistry of a series of new cyclic disulfides containing (poly)spirane 1,2‐dithiolane units are reported. Also included is a study of the self‐assembled monolayers (SAMs) of these compounds on a gold surface. The characteristics of the resultant SAMs were determined by IR spectroscopy using molecular mechanics calculations.
Synthesis and spectral data of quinoline products obtained by reaction of N‐(4‐pyridinyliden)anilines and N‐benzylidenaniline with 2,2‐dimethoxypropane (kametani reaction)
Authors: Kouznetsov Vladimir V. , Meléndez Gómez Carlos M. , Urbina González Juan M. , Stashenko Elena E. , Bahsas Ali , Amaro‐Luis Juan
Published: March 2009

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A study on interaction between N‐(4‐pyridinyliden)anilines 1‐4 and 2,2‐dimethoxypropane under Kametani reaction conditions was realized. According to the GC‐MS analysis of crude reaction, besides the needed 4‐methyl‐2‐(4‐pyridinyl)quinolines 5‐8, three collateral products: secondary amines 9‐12, 4‐(2‐methylprop‐1‐enyl)quinolines 13‐16 and 4‐(2‐methoxy‐2‐methylpropyl)quinolines 17‐20 were formed. Unexpected quinolines 13‐16 as well the desired quinolines 5‐8 were isolated and fully characterized. In contrast, a condensation of N‐benzylidenaniline 21 with 2,2‐dimethoxypropane afforded a set of different quinoline products.
Synthesis of new derivatives of thieno[2,3‐b]pyridine fused with octyl ring
Authors: Al‐Omran Fatima A. , El‐Khair Adel A.
Published: March 2009

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Derivatives of thiophene, thieno[2,3‐b]pyridine, thieno[5′,4′:4,5]pyrimido[3,2‐a]pyridine and thiepine fused with octyl ring have been synthesized and tested for antimicrobial and antifungal activities. The structure of the newly synthesized compounds have been established on the basis of their analytical and spectral data.
Synthesis and characterization of 1,3,4‐oxadiazole‐triazolopyridinone hybrid derivatives as new blue‐greenish photoluminescent materials
Authors: Chiang Kuo‐Chen , Wong Fung Fuh , Chang Chih‐Shiang , Hour Mann‐Jen , Wang Yu‐Ling , Wen Shaw‐Bing , Yeh Mou‐Yung
Published: March 2009

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Recently, New functionalized oxadiazole‐triazolopyridinone hybrid compounds were investigated as photoluminescent materials. In this work, we introduce triazolopyridinone to synthesize a series of oxadiazole‐triazolopyridinone hybrid derivatives as potential photoluminescent materials and explore the effect of modification of the triazolopyridinone moiety. The λmax values of the photoluminescence (PL) spectra of 1,3,4‐oxadiazole‐triazolopyridinone hybrids are promoted to longer wavelengths (470‐486 nm) than the traditional 1,2,3‐triazole derivatives (410‐425 nm) in solutions. PL spectra 5a, 5d, and 5g of the vacuum evaporated films on quartz substrates, with a maximum at 487 nm, shows a red‐shift (∼15‐20 nm), with respect to the solution spectrum. The solution fluorescence quantum yields (Φf) were measured, all of which fell into the range 0.65‐0.76, and were determined relative to that of 2‐phenyl‐5‐(4‐biphenyl)‐1,3,4‐oxadiazole in benzene (Φf = 0.80). 1,3,4‐Oxadiazole‐triazolopyridinone hybrid derivatives show clearly non‐reversible reduction processes in cyclic voltammogram measurements. Following spectroscopic studies and observation of the electrochemical behaviors, 1,3,4‐oxadiazole‐triazolopyridinone derivatives were determined to be potential efficient bluegreenish photoluminescent materials.
Studies with enamines: Reactivity of N,N‐dimethyl‐N‐[(E)‐2‐(4‐nitrophenyl)‐1‐ethenyl]amine towards nitrilimine and aromatic diazonium salts
Authors: Al‐Matar Hamad M. , Riyadh Sayed M. , Elnagdi Mohamed H.
Published: March 2009

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In the presence of triethylamine, cycloaddition reaction of enamine 1 with hydrazonoyl halides 2 followed by dimethylamine elimination was achieved, yielding the corresponding 1,3,4‐trisubstituted pyrazoles 4. Coupling of enamine 1 with aromatic diazonium salts afforded 2‐(arylhydrazono)‐2‐(4‐nitrophenyl)acetaldehyde 9 in good yield. Refluxing the phenyl hydrazone 9a with chloroacetone in ethanol in the presence of triethylamine afforded 1,3,5‐trisubstituted pyrazole 12a, formed via intermediate 11a. Reaction of 9a with hydroxylamine hydrochloride in ethanol in the presence of anhydrous sodium acetate yielded oxime 13a which was irradiated in a microwave oven in the presence of acetic acid to afford a mixture of 15a and 16a.
Preparation of spiro[benzoisothiazole‐isoxazole] dioxides from dilithiated c(α),O‐oximes and methyl 2‐(aminosulfonyl)benzoate
Authors: Grant Bonnie J. , Kramp Catherine R. , Knight John D. , Meierhoefer Michelle A. , Vella Jarrett H. , Sober Carolyn L. , Jones Stephen S. , Metz Clyde R. , Beam Charles F. , Pennington William T. , Vanderveer Donald G. , Dwight Camper N.
Published: March 2009

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Several dilithiated C(α), O‐oximes were prepared in excess lithium diisopropylamide‐tetramethyl‐ethylenediamine (LDA/TMEDA) and condensed with methyl 2‐(aminosulfonyl)benzoate followed by acid cyclization of intermediates to spiro(benzoisothiazole‐isoxazole) dioxides, a new spiro and fused‐ring system. Distortionless enhancement by polarization transfer (DEPT) and liquid chromatography mass spectrometry (LCMS) for all products, as well as X‐ray single crystal analysis on a representative product, were especially relevant for structure confirmation in this synthesis.
Novel azaandrostane derivatives for the synthesis of 17β‐(N‐tert‐butyl carbamoyl)‐4‐aza‐5α‐androst‐1‐ene‐3‐one
Authors: Srinivasa Rao Divvela V. N. , Trinadhachari Ganala Naga , Prabahar Koilpillai Joseph , Dandala Ramesh , Sivakumaran Meenakshisundaram , Naidu Andra
Published: March 2009

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A new industrially viable process for the preparation of 1β‐(N‐tert‐butyl carbamoyl)‐4‐aza‐5α‐androst‐1‐ene‐3‐one, also known by the generic name finasteride (6) from the new azaandrostane derivatives such as 1β‐(N‐tert‐butyl carbamoyl)‐4‐benzoyl‐4‐aza‐5α‐androstane‐3‐one (4), 1β‐(N‐tert‐butyl carbamoyl)‐4‐benzoyl‐4‐aza‐5α‐androst‐1‐ene‐3‐one (5) is reported. In this process, benzoyl group is demonstrated as a novel protecting group for lactamic NH group. The structures of newly prepared compounds were established on the basis of spectral data (IR, 1H‐NMR, and MS).
Synthesis of alkyl 6‐methyl‐4‐(2‐trifluoromethylphenyl)‐1,2,3,4‐tetrahydro‐2H‐pyrimidine‐2‐one‐5‐carboxylates possessing a N‐3 nitro substituent to determine calcium channel modulation structure‐activity relationships
Authors: Kaur Kuljeet , Knaus Edward E.
Published: March 2009

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The Bigenelli acid catalyzed condensation of 2‐trifluoromethylbenzaldehyde (1), urea (2) and an alkyl acetoacetate (3) afforded the respective alkyl (Me, Et, i‐Pr, i‐Bu) 6‐methyl‐4‐(2‐trifluoromethylphenyl)‐1,2,3,4‐tetrahydro‐2H‐pyrimidine‐2‐one‐5‐carboxylate (4‐7). Subsequent N3‐nitration of the alkyl esters (4‐7) using Cu(NO3)2 3H2O and Ac2O furnished the target alkyl 6‐methyl‐3‐nitro‐4‐(2‐trifluoromethylphenyl)‐1,2,3,4‐tetrahydro‐2H‐pyrimidine‐2‐one‐5‐carboxylates (8‐11). The N3‐nitro compounds (8‐11) were less potent calcium channel antagonists (IC50 values in the 1.9 × 10−7 to 3.9 × 10−6 M range) on guinea pig ileal longitudinal smooth muscle than the reference drug nifedipine (Adalat®, IC50 = 1.4 × 10−8 M). In vitro calcium channel modulation studies on guinea pig left atrium (GPLA) showed that the methyl and ethyl esters (8‐9) induced a weak‐to‐modest positive inotropic (agonist) effect, and that the inactive isopropyl (10) and isobutyl (11) esters did not alter the cardiac contractile force of GPLA.
Synthesis of thiazolo[3,2‐d][1,2,4] triazines through palladium‐catalyzed heteroannulation of acetylenic compounds
Authors: Heravia Majid M. , Kivanloo Ali , Rahimizadeh Mohammad , Bakavoli Mehdi , Ghassemzadeh Mitra
Published: March 2009

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The reaction of 6‐methyl‐5‐(prop‐2‐ynylthio)‐5,6‐dihydro‐1,2,4‐triazin‐3(4H)‐one 1 with various iodobenzenes 2 in the presence of palladium catalyst leads to the formation of substituted triazolotriazines.
Synthesis of new spiro‐[isothiochromene‐3,5′‐isoxazolidin]‐4(1H)‐ones
Authors: Bennani Brahim , Baba Bouchra Filali , Larbi Najib Ben , Boukir Abdelatif , Kerbal Abdelali , Mimouni Mostafa , Hadda Taibi Ben , Trzaskowski Bartosz , Jalbout Abraham F.
Published: March 2009

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A series of seven new 2′,3′,4′‐substituted spiro[isothiochromene‐3,5′‐isoxazolidin]‐4(1H)‐ones (7‐13) has been prepared in the reaction of benzylidene(phenyl)azane oxide (5) or benzylidene(methyl)azane oxide (6) with (3Z)‐3‐(4‐substituted‐benzylidene)‐1H‐isothio‐ chromen‐4(3H)‐one (1‐4). The reaction occurs by a 1,3‐dipolar cycloaddition mechanism that leads to the regiospecific formation of various spiroisoxazolidines (7‐13).
The reaction of 3,4‐diamino‐1,2,5‐oxadiazoles with formaldehyde
Authors: Kakanejadifard A. , Saniei A. , Delfani F. , Farnia M. , Najafi G. R.
Published: March 2009

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The compounds 5,6‐dihydro‐4H‐imidazo[4,5‐c][1,2,5]oxadiazole (3a, RH), 4,6,10,12‐tetramethyl‐5,6,11,12‐tetrahydro‐4H,10H‐bis(1,2,5)oxadiazolo[3,4‐d:3′,4′‐I][1,3,6,8]tetraazecine (4b, RCH3), N3,N3′‐methylenebis‐3,4‐diamino‐1,2,5‐oxadiazole (5a, RH) and N3,N3′‐methylenebis(N,N′‐dimethyl‐3,4‐diamino‐1,2,5‐oxadiazolee) (5b, RCH3) were synthesized from the reaction of formaldehyde with 3,4‐diamino‐1,2,5‐oxadiazole and N,N′‐3,4‐dimethylamino‐1,2,5‐oxadiazole in an acetonitrile.
Cycloaddition reactions of phthalimide substituted cyclic polyenes with heteroatom dienophiles
Authors: Templin Stephen S. , Wallock Nathaniel J. , Haworth Daniel T. , Donaldson William A. , Bennett Dennis W. , Siddiquee Tasneem
Published: March 2009

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The cycloaddition of 6‐phthalimidobicyclo[5.1.0]octa‐2,4‐diene and 7‐phthalimido‐1,3,5‐cycloheptatriene with nitrosobenzene and with 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione each gave a single heterocyclic product. X‐ray crystallographic analysis of 8a indicated the regio‐ and stereoselectivity of this cycloaddition.
Synthesis of some pyrazolopyrimidines as purine analogues
Authors: Ahmed Sayed A. , Hussein Ahmed M. , Hozayen Walaa G. M. , El‐Ghandour Ahmed H. H. , Abdelhamid Abdou O.
Published: March 2009

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Pyrazolo[1,5‐a]pyrimidines were synthesized from the appropriate 3‐aminopyrazoles with the appropriate sodium (3‐oxocycloalkylidene)methenolate, β‐diketone, β‐keto esters or 1,2‐disubstituted acrylonitrile. Elemental analyses, spectral data, alternative synthesis route and X‐ray elucidated structures of the newly synthesized compounds.
A new synthetic route to the synthesis of nordasycarpidone derivatives
Authors: Akdag Resmiye , Ergun Yavuz
Published: March 2009

A new synthetic route for the synthesis of the nordasycarpidone derivative 11 which has hexahydro‐1,5‐methanoazocino[4,3‐b]indol skeleton, is described. Construction of the tetracyclic structure was achieved by catalytic reduction and cyclization reaction of the nitrile derivative. Also many new tetrahydrocarbazole derivatives (4, 5, 6, 7, 8, 9) and a dasycarpidol derivative (10) were synthesized.
Synthesis of new heterocycles containing more than one 1,2,3‐thia or selenadiazole rings
Authors: Al‐Smadi Mousa
Published: March 2009

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The diketones 2a‐d with different alkyl chain length are used for the synthesis of di‐1,2,3‐thia or selenadiazole derivatives 4a‐d and 5a‐d. The diketones 2a‐d where prepared by a unique method through the reaction between the corresponding dibromoalkanes 1a‐d and ethyl acetoacetate, which are transformed into the corresponding semicarbazone derivatives 3a‐d. The di‐1,2,3‐thia or selenadiazole derivatives 4a‐d and 5a‐d were prepared from the semicarbazones derivatives 3a‐d on oxidative cyclization with thionyl chloride and selenium dioxide respectively in high yield.
Design and synthesis of diheterocyclic compounds containing tetrazolinone and 1,2,4‐triazole
Authors: Luo Yan‐Ping , Lin Long , Yang Guang‐Fu
Published: March 2009

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A novel series of 1‐(4‐chlorophenyl)‐4‐{[5‐(alkylthio)‐4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl]methyl}‐1,4‐dihydro‐5H‐tetrazol‐5‐ones 6a‐y were synthesized in good to excellent yields and their structures were identified by 1H nmr, 13C nmr, ms and elemental analysis. Determining the X‐ray crystallography of compound 6j indicated that there were strong intermolecular hydrogen bonds in the stacking interactions. The bioassay results showed that compound 6k exhibited good insecticidal activities against T cinnabarinus at the dosage of 250 mg.L−1. To our knowledge, this is the first report about the insecticidal activity of tetrazolinone derivatives.
Synthesis and herbicidal activity of 2‐(3‐(trifluoromethyl)‐5‐(alkoxy)‐1H‐pyrazol‐1‐yl)‐4‐aryloxypyrimidine derivatives
Authors: Liu Wei‐Min , Zhu You‐Quan , Wang Yi‐Feng , Liu Bin , Zou Xiao‐Mao , Yang Hua‐Zheng
Published: March 2009

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A series of 2‐(3‐(trifluoromethyl)‐5‐(alkoxy)‐1H‐pyrazol‐1‐yl)‐4‐aryloxypyrimidine derivatives were designed and synthesized. The structures of all the title compounds were confirmed by 1H NMR and elementary analysis. These compounds were screened for herbicidal activity against rape and barnyard grass. Compound B13 exhibited moderate herbicidal activity.
Copper nitrate trihydrate catalyzed efficient synthesis of bis(indolyl)methanes in acetonitrile at room temperature
Authors: Nasreen Aayesha , Varala Ravi , Adapa Srinivas R.
Published: March 2009

A catalytic amount of easily available and inexpensive Cu(NO3)3.3H2O (10 mol%) enables electrophilic substitution reaction of indole with structurally divergent aldehydes in acetonitrile to afford the corresponding bis(indolyl)methanes in moderate to excellent yields (65‐98%) at ambient temperature. The reaction is highly chemoselective and applicable only to aldehydes and not to ketones.
An efficient synthesis of new class of pyrazolo[3,4‐b]pyridine‐6‐one derivatives by a novel cascade reaction
Authors: Shi Feng , Zhang Junyong , Tu Shujiang , Jia Runhong , Zhang Yan , Jiang Bo , Jiang Hong
Published: March 2009

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A novel cascade reaction of 4‐arylidene‐2‐phenyl‐1,3‐oxazol‐5(4H)‐one with 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5‐amine was described and a number of new pyrazolo[3,4‐b]pyridine‐6‐one derivatives were synthesized. This new protocol has the advantages of shorter time, higher yields, and lower cost as well as easier operation.
(±)‐2‐alkyl‐1,2,3,4‐tetrahydroquinoline‐3‐carboxylic esters by a catalyst and pressure dependent tandem reduction‐reductive amination reaction
Authors: Bunce Richard A. , Nago Takahiro , Sonobe Nathan
Published: March 2009

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A series of 2‐(2‐nitrobenzyl)‐substituted β‐keto ester derivatives has been subjected to reductive cyclization under catalytic hydrogenation conditions. The reactions were found to be highly dependent on the catalyst and hydrogen pressure used. Hydrogenation over 5% palladium‐on‐carbon at 4 atmospheres pressure produced complex mixtures of products that included predominantly 1,2,3,4‐tetrahydroquinoline and quinoline products; at 1 atmosphere pressure, the same reactions gave mixtures containing predominantly tetrahydroquinoline and 1,4‐dihydroquinoline derivatives. Hydrogenation using 5% platinum‐on‐carbon was much cleaner and afforded the desired cis‐ and trans‐(±)‐2‐alkyl‐1,2,3,4‐tetrahydroquinoline‐3‐carboxylic esters, with the cis product predominating by ≥ 13:1.
Synthesis and some reactions of 4‐(ethoxycarbonyl)‐1,5‐diphenyl‐1H‐pyrazole‐3‐carboxylic acid
Authors: Şener Ahmet , Bildirici İshak , Tozlu İsrafil , Genç Hasan , Arısoy Kadir
Published: March 2009

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1,5‐Diphenyl‐1H‐pyrazole‐3,4‐dicarboxylic acid‐4‐ethyl ester 2, obtained from the 4‐ethoxycarbonyl‐5‐phenyl‐2,3‐furandione 1 and N‐benzylidene‐N′‐phenyl hydrazine, was converted via reactions of its acid chloride 3 with various alcohols or N‐nucleophiles into the corresponding ester 5 or amide derivatives 6, respectively. In addition, 2 was decarboxylated to give ethyl 1,5‐diphenylpyrazole‐4‐carboxylate 4. Nitrile 7 derivative of 2 was also obtained by dehydration of 6a in a mixture of SOCl2 and DMF. While cyclocondensation reaction of 2 with hydrazine hydrate leads to the formation of pyrazolo[3,4‐d]pyridazine‐4,7‐dione 8, the reaction of 3 with anhydrous hydrazine provided a new bis pyrazole derivative 9.
Competition between S‐oxidation and nitration in reactions of some β‐ and γ‐quinolinyl sulfides with nitrating mixture
Authors: Maślankiewicz Maria J. , Jaworska Maria , Lodowski Piotr
Published: March 2009

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This study was performed in order to explain different orientation in the reaction of quinolinyl sulfides with nitrating mixture, which converted on one hand quinolinyl sulfides 1, 3 and 5 to sulfoxides 2, 4 and 8, respectively, on the other hand, sulfides 6, 7 to the respective nitroderivatives 9 and 10. Competitive experiments showed following reactivity order: thianthrene 11 ≥ thianthrene 5‐oxide 12 ≥ isothioquinanthrene 3 ≥ thioquinanthrene 1 ≥ 3,3′‐diquinolinyl sulfide 5 ≥ 3,4′‐diquinolinyl sulfide 6 ≥ 4,4′‐diquinolinyl sulfide 7. Considering that NO2+ (as reactive form of nitrating mixture) attacks the most electronodonating (sulfur or carbon) center the reactivity order well correlates with the results of HOMO as well as MEP calculations.
Synthesis of beta‐proline like derivatives and their evaluation as sodium channel blockers
Authors: Muraglia Marilena , Franchini Carlo , Corbo Filomena , Scilimati Antonio , Tortorella Vincenzo , Sinicropi Maria Stefania , De Luca Annamaria , De Bellis Michela , Camerino Diana Conte
Published: March 2009

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A simple and convenient procedure for the preparation of beta‐proline like derivatives in their racemic and optically active forms has been reported. The compounds have been screened for their potential activity as sodium channel blockers.
BF3·Et2O promoted selective synthesis of benzimidazoles
Authors: Rajanarendar E. , Ramesh P. , Rao E. Kalyan , Mohan G. , Reddy A. Siva Rami
Published: March 2009

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Benzimidazoles 3, 6 and 9 have been synthesized selectively in excellent yields by cyclocondensation of β‐(3‐methyl‐5‐styryl‐4‐isoxazolyl amido) benzoic acids, acrylic acids and propionic acids with 1,2‐phenylene diamines by employing BF3·Et2O as the catalyst. When the same reaction was carried out in pyridine it resulted in mixture of products in each case (3 & 4, 6 & 7 and 9 & 10). Other methods tried by using polyphosphoric acid, HCl, TFA also led to mixtures of 3 & 4, 6 & 7 and 9 & 10 in each case, similar to that of pyridine reaction.
Microwave assisted synthesis of thiazolo[3,2‐b][1,2,4]‐triazoles containing 1,8‐naphthyridine moiety
Authors: Mogilaiah K. , Prashanthi M. , Kavitha S. , Babu H. Sharath
Published: March 2009

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A simple and efficient protocol for the synthesis of 5‐aryl‐2‐(2‐substituted‐1,8‐naphthyridin‐3‐yl)‐thiazolo[3,2‐b][1,2,4]triazoles (4) is achieved by cyclocondensation of 3‐(2‐substituted‐1,8‐naphthyridin‐3‐yl)‐1,2,4‐triazoles (3) with α‐halogenoketones in anhyd. methanol under microwave irradiation. The products are obtained in good yields and in a state of high purity.
Phenacylsulfonylacetic acid methyl ester‐synthon for 1,2,3‐selena/thiadiazoles and 2H‐diazaphospholes
Authors: Padmavathi Venkatapuram , Mahesh Konda , Thriveni Pinnu , Reddy Tippireddy Venkata Ramana
Published: March 2009

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A new class of 1,2,3‐selena/thiadiazoles and 2H‐diazaphospholes were synthesized by exploiting α‐ketomethylene group in phenacylsulfonylacetic acid methyl ester.
Reaction of 1‐acylthiosemicarbazides with ethenetetracarbonitrile
Authors: Hassan Alaa A. , Mourad Aboul‐Fetouh E. , Abou‐Zied Ashraf H.
Published: March 2009

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1‐Acylthiosemicarbazides 9a‐d reacted with ethenetetracarbonitrile (TCNE, 2) in ethyl acetate with formation of N′‐(4‐amino‐5,6‐dicyano‐2H‐1,3‐thiazin‐2‐ylidene) substituted hydrazide 10a‐d, N′‐(5‐amino‐3,4‐dicyano‐2H‐pyrrol‐2‐ylidene)‐2‐substituted hydrazide 11a‐d and 2‐substituted imidazo[2,1‐b][1,3,4]‐oxadiazole‐5,6‐dicarbonitrile 12a‐d. Rationales for the conversions observed are presented.
An efficient and greener approach to the synthesis of 3,5‐dicyanopyridin‐2(1H)‐one derivatives in aqueous media under microwave irradiation conditions
Authors: Jia Runhong , Tu Shujiang , Zhang Yan , Jiang Bo , Zhang Junyong , Yao Changsheng , Shi Feng
Published: March 2009

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A facile and greener synthesis of a series of 3,5‐dicyanopyridin‐2(1H)‐one derivatives was accomplished via the one‐pot reaction of aldehyde, malononitrile and sodium hydroxide in aqueous media under microwave irradiation. This method had several advantages such as shorter route and time, lower cost, reduced environmental impact.
Synthesis and biological study of novel methylene‐bis‐chalcones and substituted methylene‐bis‐pyrimidines/pyrimidinones
Authors: Nagaraj Adki , Reddy Cherkupally Sanjeeva
Published: March 2009

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A series of novel methylene‐bis‐chalcones was prepared by the reaction of 5,5′‐methylene‐bis‐salicylaldehyde with different acetophenones, subsequent treatment of methylene‐bis‐chalcones with urea/thiourea gave the corresponding methylene‐bis‐pyrimidinones/methylene‐bis‐mercaptopyrimidines in good yields. Characterization of the new compounds has been done by means of IR, 1H NMR, MS and elemental analysis. The antibacterial, antitubercular and antifungal activity of the compounds has also been evaluated.
Studies with enaminones: Formation of a N,O‐cyclicacetal on coupling of 3‐dimethylamino‐1‐hydroxyphenyl‐2‐propenone with arenediazonium salts
Authors: Al‐Zaydi Khadijah M. , Borik Rita M. , Elnagdi Mohamed H.
Published: March 2009

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Coupling the title compound 3 with arenediazonium salts affords the arylhydrazonochromones 6. The latter compounds react with hydrazine hydrate to yield novel pyrazoles 11.
One‐pot solvent and catalyst‐free synthesis of functionalized 1,8‐naphthyridines and quinolines by microwave irradiation
Authors: Goswami Shyamaprosad , Jana Subrata , Hazra Anita , Adak Avijit Kumar
Published: March 2009

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A series of functionalized, aryl substituted naphthyridines and quinolines has been synthesized by microwave‐assisted one‐pot two‐component synthesis under solvent‐free conditions in good yields by the reaction of a variety of aryl or heteroaryl amines and aryl vinyl ketones. A combinatorial type approach for a one‐step microwave reaction has been developed where a ring‐closing condensation is followed by a spontaneous aromatization to afford the functionalized aryl substituted 1,8‐naphthyridines and quinolines.
Facile three‐component one‐pot synthesis of indeno‐[1,2‐b]quinolin‐9,11(6H,10H)‐dione derivatives
Authors: Chen Yan , Tu Shujiang , Jiang Bo , Shi Feng
Published: March 2009

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One‐pot three‐component cyclocondensation of aldehydes, 1,3‐indanedione and enaminones proceeds in the presence of acetic acid to afford Indeno[1,2‐b]quinolin‐9,11(6H,10H)‐dione derivatives, The method has the advantage of excellent yields(85‐94%) and simple workup procedure.
Synthesis of novel coumarin and benzocoumarin derivatives and their biological and photophysical studies
Authors: Abd‐El‐Aziz Alaa S. , Mohamed Hany M. , Mohammed Shawkat , Zahid Shamsulhaq , Ata Athar , Bedair Ahmed H. , El‐Agrody Ahmed M. , Harvey Pierre D.
Published: March 2009

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Several derivatives of coumarin‐3N‐carboxamides (3‐21) have been prepared via the reaction of the coumarin‐3‐carbonyl chloride (1) with a number of nucleophiles. Novel double‐headed coumarin‐3N‐carboxamides (26‐33) were also produced using the same method. The Pechmann‐Duisberg reaction was applied to prepare new benzo[f]‐ benzo[h]coumarins and 4‐(chloromethyl)‐pyrano[3,2‐c]coumarin‐2‐one (36‐42). The reaction of 1‐chloromethylbenzo[f]coumarins (36) with cyanide anion under different reaction conditions was also investigated in order to assess its suitability for nucleophilic substitution reactions as well as ring transformation products (43‐49). Synthesis of 1‐((benzo[d]thiazol‐2‐yl)methyl)‐9‐hydroxybenzo[f]coumarin (50) represented the first example of methylene bridge‐head heterocyclecontaining benzo[f]coumarin. Some of the newly prepared coumarins exhibited anti‐bacterial activity against Gram Positive and Gram negative bacteria. Compound 36d was found to be active against all the screened bacteria. Photophysical studies were performed on selected fluorescent benzo[f]‐ and benzo[h]coumarin and the quantum yields were also calculated. All new compounds were characterized by IR, MS, 1H and 13C NMR, as well as elemental analysis.
Microwave‐assisted efficient synthesis of benzo[4,5]imidazo[1,2‐a]‐pyrimidine derivatives in water under catalyst‐free conditions
Authors: Tu Shujiang , Shao Qingqing , Zhou Dianxiang , Cao Longji , Shi Feng , Li Chunmei
Published: March 2009

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Benzo[4,5]imidazo[1,2‐a]pyrimidine derivatives were synthesized via the three‐component reaction of aldehyde, β‐dicarbonyl compound and 2‐aminobenzimidazole in water under microwave irradiation and without catalyst conditions. The new protocol has the advantages of higher yield, lower cost, reduced environment impact, wider scope and convenient procedure.
N‐alkyl‐4‐chloro‐1H‐benzo[c][1,2]thiazine‐3‐carbaldehyde‐2,2‐dioxides—New functional benzothiazine derivatives
Authors: Volovenko Yulian , Volovnenko Tatyana , Popov Kirill
Published: March 2009

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A synthesis of N‐alkyl‐4‐chloro‐1H‐benzo[c][1,2]thiazine‐3‐carbaldehyde‐2,2‐dioxides is described. Reactivity of new β‐chloroaldehydes is investigated, a number of novel benzo[c][1,2]thiazine derivatives are synthesized and characterized using 1H, 13C‐NMR, MS and elemental analysis.
A new method for the synthesis of bicyclic pyran acetals
Authors: Ergunes Duygu , Kumbaraci Volkan , Karliga Bekir , Talinli Naciye
Published: March 2009

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cis‐Fused bicyclic acetals were obtained from the unusual cyclization reaction between diols and dihydropyran. Furothiopyran, substituted pyranopyrans, and pyranooxepine and pyranobenzoxepine compounds were obtained with high diastereoselectivity and cis‐diastereomers were obtained in high yields.
A highly efficient method for solvent‐free synthesis of bis(arylmethylidene)piperidinones
Authors: Saeed Abaee M. , Mojtahedi Mohammad M. , Sharifi Roholah , MehdiZahedi M.
Published: March 2009

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A remarkably efficient double crossed aldol condensation of piperidin‐4‐one with various aromatic aldehydes is described at room temperature in the presence of diethylamine and lithium perchlorate under solvent‐free conditions. Excellent yields of 3,5‐bis(arylmethylidene)piperidinones are achieved in a facile one‐pot general procedure. Structure of the products is determined by spectroscopic methods and elemental analysis.
Novel approach for the conversion of natural Δ3 cephalosporin derivatives into corresponding Δ2 cephalosporin derivatives
Authors: Rao Korrapati. V. V. Prasada , Dandala Ramesh , Handa Vija Y. K. , Kamat Anand. G. , Rao Inti. V. Subramanyeswara , Rani Ananta , Naidu Andra
Published: March 2009

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A simple one pot synthetic method for the isomerization of cephem double bond from the natural 3‐position to 2‐cephem positions is affected by silylation. Thus cephalosporin acids are treated with Ntrimethylsilylacetamide (MSA) or N,O‐bis(trimethylsilyl)acetamide (BSA) and the resulting silyl esters are treated with triethylamine at ambient temperature in the same pot to afford Δ2‐cephalosporins, which are potentially related compounds in cephalosporin antibacterial compounds.
Synthesis of N‐pivot lariat ethers
Authors: Elwahy Ahmed H. M. , Abbas Ashraf A.
Published: March 2009

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This review covers the main strategies for the synthesis of N‐pivot lariat ethers as well as their specific syntheses.
Regioselective three‐component synthesis of novel indeno[1,2‐b]‐pyrazolo[4,3‐e]pyridines‐fused derivatives of 4‐azafluorenone alkaloid
Authors: Quiroga Jairo , Cobo Débora , Insuasty Braulio , Abonía Rodrigo , Cruz Silvia , Nogueras Manuel , Cobo Justo
Published: March 2009

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New fused indeno[1,2‐b]pyridine derivatives have been prepared in a multicomponent reaction from benzaldehydes, indanedione and the appropriate aminoheteroaryl compound. The simple methodology permitted the syntheses of a series of indeno[1,2‐b]pyrazolo[4,3‐e]pyridines 4 from 5‐aminopyrazol 1 and modulated by the corresponding benzaldehyde 2.
Benzobis(pyrrolopyrimidopiridazines): Molecular structure and properties of the first π‐electronic analogues of dibenzo[a,o]picene
Authors: Serdyuk Olga V. , Gulevskaya Anna V. , Pozharskii Alexander F. , Avakyan Vadim E.
Published: March 2009

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Molecular structure, aromaticity and some spectral properties of benzobis(pyrrolopyrimidopiridazines) 2 that are the first π‐electronic analogues of the still unknown dibenzo[a,o]picene are discussed.
Synthesis and photochemical properties of trans‐2‐(2‐aryl‐ or heteroarylvinyl)‐4,5‐dichloropyridazin‐3(2H)‐ones
Authors: Yim Heung‐Seop , Kim Mi‐Ra , Sung Gi‐Hyeon , Chung Hyun‐A , Lee Jin‐Kook , Lee Sang‐Gyeong , Yoon Yong‐Jin
Published: March 2009

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trans‐2‐(2‐Aryl‐ or heteroarylvinyl)‐4,5‐dichloropyridazin‐3(2H)‐ones 3 were synthesized from 4,5‐dichloropyridazin‐3(2H)‐one via 2 step. The photochemical behavior of 3 in THF, methylene chloride, acetonitrile and methanol is dependent on the kind of aryl or heterocyclic ring and the solvent polarity
Preparation and crystal structures of two 3‐anthracenyl isoxazolyl sulfonamides
Authors: Li Chun , Twamley Brendan , Natale Nicholas R.
Published: March 2009

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Lateral metalation and oxidation of 3‐(9′‐anthryl)‐isoxazoles (1), using Davis' oxaziridine (6), produced the desired hydroxylation (2), along with sulfonamide adduct (3), and in the case of the use of butyl lithium as base, butyl addition products (4) and (5). Structures of isoxazole sulfonamides (3a) and (5a), were obtained as the SR/RS‐diastereomer, however, studies indicate that this is a consequence of the crystallization process. Metalation studies with isoxazole (8) demonstrate that hydroxylation (9), can be carried out cleanly, minimizing formation of (10), using camphorsulfonyloxaziridine (7) as an electrophile.
Reaction of 6‐aryl‐ or styryl‐4‐methylsulfanyl‐2‐oxo‐2H‐pyrans with active methylene compounds and fluorescence properties of the products
Authors: Mizuyama Naoko , Murakami Yuka , Nakatani Takatoshi , Kuronita Keiko , Kohra Shinya , Ueda Kazuo , Hiraoka Kyoko , Tominaga Yoshinori
Published: March 2009

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New 2‐pyrone derivatives, dialkyl 3‐cyano‐6‐phenyl‐2‐oxo‐2H‐pyran‐4‐ylmalonates and alkyl 3‐cyano‐6‐phenyl‐2‐oxo‐2H‐pyran‐4‐ylacetates, which were easily prepared by the reaction of 6‐aryl‐4‐methyl‐sulfanyl‐2‐oxo‐2H‐pyran‐3‐carbonitriles with active methylene compounds in the presence of potassium carbonate, show fluorescence emission radiation. The light‐emitting region of dimethyl 3‐cyano‐6‐(4‐N,N‐dimethylamino)styryl‐2‐oxo‐2H‐pyran‐4‐ylmalonate (7h) was 620 nm in dichloromethane, making this compound a typical red fluorescent compound. Methyl 8‐hydroxy‐6‐methyl‐1‐oxo‐3‐phenyl‐1H‐pyrano‐[3,4‐c]pyridine‐5‐carboxylate deriv‐atives also showed fluorescence in the solid state. This is the first example of fluorescence in fused 2‐pyrone derivatives.
Dicyanomethylene compounds and heterocyclization of acylthiosemicarbazides
Authors: Hassan Alaa A. , Mourad Aboul‐Fetouh E. , Abou‐Zeid Ashraf H.
Published: March 2009

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(1,3‐Dioxo‐2,3‐dihydro‐1H‐inden‐2‐ylidene)propanedinitrile (1, in ethyl acetate solution), 3‐(dicyano‐methylene)‐2‐indolone (2, in ethanol/piperidine solution) and 7,7′,8,8′‐tetracyanoquinodimethane (3, in pyridine solution) act on substituted acylthiosemicarbazides 4a‐d, forming the derivatives of oxoindeno‐pyrrolylidenehydrazide (5a‐d and 7a‐d), thiazoloindolylidenehydrazide (12a‐d), pyrroloindolylidene‐hydrazide (13a‐d) and spiro[pyrrolylidene‐4,1′(cyclohexa‐2′,5′‐dienylidene)]propanedinitrile (18a‐d). Rationales for these conversiones involving the nucleophilic addition on dicyanomethylene carbon atom are presented.
An efficient and facile microwave‐assisted synthesis of benzo[b][4,7]phenanthroline derivatives in water
Authors: Shi Feng , Zhou Dianxiang , Li Chunmei , Shao Qingqing , Cao Longji , Tu Shujiang
Published: March 2009

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A series of benzo[b][4,7]phenanthroline derivatives were synthesized via a three‐component reaction of aromatic aldehydes, 6‐aminoquinoline and either 1,3‐cyclohexanedione or dimedone in water under microwave irradiation without use of any catalyst. This method has the advantages of short reaction time, high yields, low cost and environmental friendliness as well as easy operation.
Synthesis of novel aromatic macrolactones via ring closing metathesis of substituted phenylalkanoic acid allylic esters
Authors: Brown David P. , Duong Hoan Q.
Published: March 2009

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Stable aromatic macrolactones have been synthesized and characterized from 2‐ and 3‐substituted phenylalkanoic acid systems in modest yields.
Synthesis of a peptide nucleic acid with a novel 1‐methyl‐6‐mercaptopurine base
Authors: Aboul‐Fadl Tarek , Rajeev Gopalan , Broom Arthur D.
Published: March 2009

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A novel peptide nucleic acid (PNA) monomer 16 containing a novel 1‐methyl‐6‐mercaptopurine base was synthesized by coupling the in situ generated acid chloride of (1‐methyl‐6‐mercaptopurin‐9‐yl)acetic acid (6) into an L‐lysine backbone (13) using 10% CCl4 in pyridine and Ph3P. Compound 6 was synthesized from 6‐mercapto‐1‐methylpurine and ethylbromoacetate in the presence of NaH followed by alkaline hydrolysis and subsequent neutralization with a cation exchange resin. The L‐lysine backbone (13) was obtained by the reaction of Nϵ‐CBZ‐L‐lysine allyl ester with Boc‐aminoactaldehyde in the presence of NaBH3CN under reductive amination conditions. Oligomerization of the monomer 16 to PNA analogues was achieved using BOC‐BHA‐PEG‐PS resin as a solid support and the in situ generated acid chloride of 16 by 10% CCl4 in DCM in the presence of Ph3P.
One‐pot synthesis of N2‐aminoprotected 6‐substituted and cycloalka[d] 4‐trifluoromethyl‐2‐acetylaminopyrimidines
Authors: Bonacorso Helio G. , Ferla Adriana , Cechinel Cleber A. , Zanatta Nilo , Martins Marcos A. P.
Published: March 2009

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The one‐pot synthesis of a novel series of amino‐protected 6‐alkyl‐, 6‐aryl‐, 6‐heteroaryl‐ and 5,6‐fused‐cycloalkane 4‐trifluoromethyl‐2‐acetylaminopyrimidines, where alkyl = Me; aryl = Ph, 4‐CH3Ph, 4‐FPh, 4‐ClPh, 4‐BrPh, 4‐OCH3Ph, 4‐NO2Ph, 4,4′‐biphenyl, 1‐naphthyl; heteroaryl = 2‐thienyl, 2‐furyl and cycloalkyl = c‐C6H4, c‐C7H5 from the reaction of substituted 4‐methoxy‐1,1,1‐trifluoroalk‐3‐en‐2‐ones with 1‐acetylguanidine in acetonitrile or propan‐2‐ol as solvent, is reported. The acetylamino group of 2‐acetylaminopyrimidines was hydrolyzed under three different conditions to afford the corresponding free 2‐aminopyrimidines.
A short and convenient synthesis and evaluation of the antiinfective properties of indoloquinoline alkaloids: 10H‐Indolo[3,2‐b]quinoline and 7H‐indolo[2,3‐c]quinolines
Authors: Etukala Jagan R. , Kumar E. V. K. Suresh , Ablordeppey Seth Y.
Published: March 2009

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10H‐Indolo[3,2‐b]quinoline and 7H‐indolo[2,3‐c]quinoline have been synthesized in two steps using a modified approach to our previous reported method. Starting from commercially available 3‐aminoquinoline and phenylboronic acid, the first step involved a copper acetate‐catalyzed coupling reaction and the second utilized a palladium acetate‐catalyzed intramolecular arylation reaction in the presence of trifluoroacetic acid as solvent. The anti‐infective activity of a selected number of the compounds was also evaluated.
Conventional and microwave irradiation assisted synthesis of new 1,2,4‐triazepine‐3‐thiones
Authors: Aly Ashraf A. , Hassan Alaa A , El‐Sheref Essmat M. , Mohamed Mamdouh A. , Brown Alan B.
Published: March 2009

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New 1,2,4‐triazepine‐3‐thiones have been obtained during the respective reactions of N‐substituted‐hydrazino carbothioamides with dimethyl acetylenedicarboxylate and dibenzoyl acetylene under prolonged reflux in acetic acid and/or DMF. However, the reaction of the starting materials in DMF under microwave irradiation afforded the same products in higher yields within a few minutes.
An efficient synthesis of 4‐alkoxy‐5,6‐dihydro‐furo(and ‐thieno)[2,3‐d]pyrimidines using zinc chloride/triethylamine reagent system
Authors: Maruoka Hiroshi , Okabe Fumi , Yamagata Kenji
Published: March 2009

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The one‐pot synthesis of 4‐alkoxy‐5,6‐dihydro‐furo(and ‐thieno)[2,3‐d]pyrimidines is described. The reactions of 2‐benzamido‐4,5‐dihydro‐3‐furan(and ‐3‐thiophene)carbonitriles 1a‐d and 2a‐c with ethanol and/or methanol in the presence of zinc chloride and triethylamine gave the corresponding 4‐alkoxy‐5,6‐dihydro‐furo(and ‐thieno)[2,3‐d]pyrimidines 3a‐d, 4a‐d, 5a‐c and 6a‐c.
Microwave‐promoted oxidation of 1,3,5‐trisubstituted 4,5‐dihydro‐1H‐pyrazoles byin‐situgeneration of NO+and NO respectively from sodium nitrite and sodium nitrate in acetic acid
Authors: Azarifar Davood , Maleki Behrooz , Sahraei Mahta
Published: March 2009

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Microwave‐assisted aromatization of 1,3,5‐trisubstituted 4,5‐dihydro‐1H‐pyrazoles byin‐situgeneration of NO+and NO2+respectively from sodium nitrite and sodium nitrate in acetic acid has been carried out efficiently under mild reaction conditions in good to excellent yields.
Novel C‐acylated triazole derivatives of ravuconazole, an azole antifungal agent
Authors: Kim Oak , Zhang Yunhui , Wichtowski John , Huang Stella , Fung‐Tomc Joan , Bronson Joanne , Ueda Yasutsugu
Published: March 2009

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Novel C‐acylated triazoles were synthesized from ravuconazole via bicyclic triazole lactone. The synthesis and antifungal activity of these C‐acylated derivatives are described.
Synthesis of 4H‐indeno[1,2‐b]thiophenes, 8H‐indeno[2,1‐b]‐thiophenes and 8H‐indeno[2,1‐b]furans having acrylic acid unit
Authors: Jeon Ki Joon , Lee Kee‐Jung
Published: March 2009

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Treatment of methyl propiolate and 2‐(thiophen‐2‐yl)benzaldehyde, 2‐(thiophen‐3‐yl)benzaldehyde or 2‐(furan‐3‐yl)benzaldehyde with tetrabutylammonium iodide/zirconium (IV) chloride or treatment of methyl acrylate and the same aldehydes with 1,4‐diazabicyclo[2,2,2]octane and triethanolamine induce an aldol‐type reaction to furnish Baylis‐Hillman adducts β‐iodo‐α‐(hydroxymethyl)acrylates or α‐(hydroxy‐methyl)acrylates, respectively. These can be used for the preparation of indenothiophenes and indenofurans having acrylic acid unit by intramolecular Friedel‐Crafts reaction with sulfuric acid in tetrachloromethane.
Michael addition of dimedone with α,β‐unsaturated ketones: Synthesis of quinoline and chromene derivatives
Authors: Kendre Dhananjay B. , Toche Raghunath B. , Jachak Madhukar N.
Published: March 2009

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A series of quinoline and chromene derivatives has been synthesized by Michael addition of dimedone 1 with 2‐aroyl‐3‐arylacrylonitrile 2 and study of absorption and fluorescence maxima of quinolines.
An Efficient synthesis of pyrimido[4,5‐b]quinoline and indeno[2′,1′:5,6]pyrido[2,3‐d]pyrimidine derivatives via multicomponent reactions in ionic liquid
Authors: Ji Shun‐Jun , Ni Sai‐Nan , Yang Fang , Shi Jing‐Wen , Dou Guo‐Lan , Li Xiao‐Yue , Wang Xiang‐Shan , Shi Da‐Qing
Published: March 2009

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A series of pyrimido[4,5‐b]quinoline and indeno[2′,1′:5,6]pyrido[2,3‐d]pyrimidine derivatives were synthesized via the three‐component reaction of an aldehyde, 6‐aminopyrimidine‐2,4‐dione and 5,5‐dimethyl‐1,3‐cyclohexanedione or 1,3‐indanedione in ionic liquid 1‐n‐butyl‐3‐methylimidazolium bromide ([bmim]Br). This protocol has the advantages of easier work‐up, milder reaction conditions, high yields and an environmentally benign procedure compared with other methods.
A novel synthesis of EGFR‐tyrosine‐kinase inhibitors with 4‐(indol‐3‐yl)quinazoline structure
Authors: Lüth Anja , Löwe Werner
Published: March 2009

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The epidermal growth factor (EGF) family of membrane receptors has been identified as a key element in the complex signaling network that is utilized by various classes of cell‐surface receptors. A new synthetic pathway of 4‐(indol‐3‐yl)quinazolines 15 and 16 is described using cross coupling reactions with quinazoline‐ and indole moieties. The synthesized compound 15 is a new dual and high potent EGFR‐ and HER‐2‐tyrosine kinase inhibitor with excellent cytotoxic properties at different cell lines. Furthermore this substance class shows remarkably strong fluorescence.
N‐alkylated 3,5‐bis(arylidene)‐4‐piperidones. Synthetic approaches, X‐ray structure and anticancer activity
Authors: Makarov Michael V. , Odinets Irina L. , Lyssenko Konstantin A. , Rybalkina Ekaterina Yu. , Kosilkin Ilya V. , Antipin Mikhail Yu. , Timofeeva Tatiana V.
Published: March 2009

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In a search for cytotoxic fluorescent materials a series of N‐alkylated and N,N‐dialkylated 3,5‐bis(arylidene)piperidones was synthesized. Alkylation of 3,5‐bis(arylidene)‐4‐piperidone afforded quaternary salts only while condensation of N‐alkyl‐4‐piperidones with substituted benzaldehydes was a convenient route to the corresponding N‐alkylated compounds. Compounds and their pharmaceutically acceptable salts demonstrated high activity against resistant human lung carcinoma cell line A549 with IC50 values in the range of 0.3‐6.5 μM.
Synthetic and spectroscopic studies of some new 2‐[1‐aryl‐4{4‐methoxyphenyl}‐6‐thioxo‐1,6‐dihydro‐1,3,5‐triazinyl]amino/hydrazonothiazolidin‐4‐ones
Authors: Roychowdhuary P. K. , Mehrotra Sangeeta , Srivastava Sugandh , Upadhay K. K. , Mishra Rakesh K. , Kumar Ajit , Upadhyay Shalini
Published: March 2009

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A series of 4‐thiazolidinones having triazinethione moieties have been synthesized by the systematic chemical modification of S‐benzylmercapto‐1‐aryl‐4‐(4‐methoxyphenyl)‐1,6‐dihydro‐1,3,5‐triazine‐6‐thione.
Synthesis and in vitro antiproliferative activity of new substituted benzo[3′,2′:5,6]thiopyrano[4,3‐d]pyrimidines
Authors: Marini Anna Maria , Da Settimo Federico , Salerno Silvia , La Motta Concettina , Simorini Francesca , Taliani Sabrina , Bertini Daniele , Gia Ornella , Dalla Via Lisa
Published: March 2009

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The synthesis of new planar benzo[3′,2′:5,6]thiopyrano[4,3‐d]pyrimidine derivatives, carrying different side groups in the 2 position, is described. The novel substituted pyrimidines were obtained by reaction of the key intermediate 3‐dimethylamino methylen‐7‐methoxy‐2,3‐dihydrobenzo[3′,2′:5,6]thiopyran‐4(4H)‐one, characterized by a reactive group adjacent to the CO function, with the suitable binucleophile amidines in a basic medium. All the new compounds were evaluated for the antiproliferative ability by an in vitro assay on two human tumour cell lines (HL‐60 and HeLa), and the 2‐phenyl substituted derivative showed the capacity to inhibit cell growth on HL‐60. Linear flow dichroism measurements indicated the inability to form a molecular complex with DNA.
Full Characterization and some reactions of 1‐(2‐adamantyl)‐3‐(1‐adamantyl)aziridin‐2‐one
Authors: Lengyel István , Taldone Tony , Lyons Theresa , Cesare Victor
Published: March 2009

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We found that 1‐(2‐adamantyl)‐3‐tert‐butylaziridin‐2‐one (5a) is unstable. It slowly decomposes at room temperature, although detectable by IR spectroscopy (1840 cm−1 band in CCl4). On the other hand, a closely related analogue, 1‐(2‐adamantyl)‐3‐(1‐adamantyl)aziridin‐2‐one (5b), is very stable, in concurrence with an earlier report [1]. We fully characterized aziridinone 5b, identified its thermal decomposition products (7 and 8) and reacted it with two aprotic ionic (tBuO− and HO−) and one protic non‐ionic nucleophile (benzylamine). All three products (9b, 10, and 11) result from exclusive cleavage of the lactam (1‐2) bond.
Synthesis of 5‐mono‐ and 5,7‐diamino‐pyrido[2,3‐d]‐pyrimidinediones with potential biological activity by regioselective amination
Authors: Van Tinh Dang , Stadlbauer Wolfgang
Published: March 2009

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5‐Alkyl‐/arylamino‐ and 5,7‐dialkyl/arylamino‐pyrido[2,3‐d]pyrimidine‐2,4‐diones (4,5, 7‐9) were prepared from the corresponding 5,7‐dichloro‐pyrido[2,3‐d]pyrimidine‐2,4‐diones 2 with aliphatic and aromatic amines 3 and 6 in a regioselective reaction. The 7‐monoazides 10, obtained by azidation of 5‐amino‐7‐chloro derivatives 4, were converted to iminophosphoranes by reaction with triphenyl‐phosphane via Staudinger reaction. Hydrolysis with aqueous acetic acid produced in one step 7‐unsubstituted‐amino‐pyrido[2,3‐d]pyrimidine‐2,4‐diones 12. In a similar amination reaction, 5‐chloropyrido[2,3‐d]pyrimidine‐2,4,7‐triones 13 were aminated and formylated to 5‐alkyl/arylamino‐6‐formyl derivatives 14‐16 in a combined one‐step‐reaction with bulky arylamines or alkylamines in the presence of dimethylformamide.
A highly efficient microwave‐assisted synthesis of chromeno‐[3,4‐b][4,7]phenanthroline derivatives through multicomponent reactions in water
Authors: Zhuang Qiya , Zhou Dianxiang , Tu Shujiang , Li Chunmei , Cao Longji , Shao Qingqing
Published: March 2009

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A short and simple synthesis of chromeno[3,4‐b][4,7]phenanthroline derivatives was accomplished by three‐component reactions involving an aromatic aldehyde, 6‐aminoquinoline and 4‐hydroxycoumarin in water, under microwave irradiation without use of any catalyst. This protocol has the advantages of short reaction time, high yields, low cost and being environmental‐friendly as well as easy operation.
Synthesis of substituted amino‐cycloalkyl[b]thieno‐[3,2‐e]pyridines
Authors: Seck Pierre , Thomae David , Kirsch Gilbert
Published: March 2009

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An efficient two respectively three steps procedure for the synthesis of cycloalkyl[b]thieno[3,2‐e]‐pyridine amines was developed and in general good to very good yields were obtained.
Preparation of analogues of efaroxan and KU14R as potential imidazoline receptor subtype 3 ligands
Authors: Farn Richard D. , Ramsden Christopher A. , Morgan Noel G.
Published: March 2009

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The preparation and characterization of new analogues of the imidazoline insulin secretagogue efaroxan 1 are described. These include 1,2,4‐triazole, 1,3,4‐oxadiazole, pyrimidine, 1,4,5,6‐tetrahydropyrimidine and 1,2‐dihydro‐1,2,4,5‐tetrazine analogues. Bromination of 2,3‐dihydro‐2‐ethylbenzo[b]furan‐2‐carbonitrile 19 gives the 3,3‐dibromo analogue 28, which is readily hydrolysed to the corresponding ketone 29. Reduction of this ketone gives the alcohol 31 as a mixture of diastereoisomers that is converted to the fluoride 32 using diethylaminosulfur trifluoride.
A convenient and practical synthesis of olmesartan medoxomil methyl ether
Authors: Pati Hari Narayan , Lahiri Saswata , Sabbam Ramesh Kumar , Vangala Vijaya Bhaskar , Ramalingam Boobalan , Hiriyanna Salmara Ganeshbhat , Bose Prosenjit
Published: March 2009

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Synthesis of Olmesartan medoxomil methyl ether (2), a potential impurity of Olmesartan medoxomil (1), an angiotensin II receptor blockers is reported for the first time.
A facile synthesis and heteroannulation of thiazolopyrimidine and related heterocyclic systems
Authors: Aly A. A.
Published: March 2009

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Reaction of pyrimidinylacetic acid 2 with different electrophilic and nucleophilic reagents gave annulated pyrimidine derivatives 3‐11, respectively. Compound 3 was transformed to pyrimidinylacetyl azide 12, which upon heterocyclization with active methylene compounds, acidic and basic reagents furnished functionally substituted heteroaromatic compounds 13‐21, respectively. The antimicrobial activity of some synthesized compounds was investigated. The structures of the synthesized derivatives were elucidated by elemental and spectral analyses.