bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and structure of novel 3,4‐annelated coumarin derivatives
Authors: Dekić Milan S. , Dekić Biljana R. , Dekić Vidoslav S. , Deki Stojadin V. 
Published: March 2009

Abstractmagnified imageCondensation of 4‐chloro‐2‐oxo‐2H‐chromene‐3‐carbonitrile (1) with heteroarylamines 2a‐d in acetonitrile containing a catalytic amount of triethylamine followed by spontaneous intramolecular cyclization gave the novel coumarin derivatives 3a‐d, respectively. These compounds underwent acid hydrolysis giving the corresponding oxoderivatives 4a‐d. The structural assignments of the synthesized compounds were based on elemental, IR, 1H and 13C NMR analyses.
Preparation of 5‐bromo‐6‐phenylimidazo[2,1‐b][1,3,4]thiadiazol‐2‐ylamines
Authors: Safarov Saifidin , Rahmon Rahmonov , Kukaniev Muhamacho Amadovich , Schollmeyer Dieter , Karpuk Elena , Meier Herbert 
Published: March 2009

Abstractmagnified imageThe reaction of primary or secondary amines with 2,5‐dibromo‐6‐phenylimidazo[2,1‐b][1,3,4]‐thiadiazole (5) leads to a chemoselective replacement of the 2‐Br substituent. The process represents a convenient route to the corresponding 2‐ylamines 7a‐d. Hydrazine reacts in an analogous fashion (5 → 7e). The structure determinations are based on an X‐ray crystal structure analysis and on one‐ and two‐dimensional NMR measurements.
Photodegradation of 2‐mercaptobenzothiazole disulfide and related benzothiazoles
Authors: Zajíčková Zuzana , Párkányi Cyril 
Published: March 2009

Abstractmagnified imageThe photodegradation of 2‐mercaptobenzothiazole disulfide, 2‐mercaptobenzothiazole and benzothia‐zole was investigated. Benzothiazole was found to undergo photodimerization into 2,2′‐bibenzothiazole, and in the presence of oxygen to give two additional photoproducts ‐ 2‐hydroxybenzothiazole and 2‐methylbenzothiazole. The major degradation products of 2‐mercaptobenzothiazole are benzothiazole and 2‐benzothiazolesulfonic acid, with 2,2′‐thiobisbenzothiazole and 2‐mercaptobenzothiazole disulfide as the minor degradation products. Direct photolysis of 2‐mercaptobenzothiazole disulfide gave 2‐mercapto‐benzothiazole and in acetonitrile 2‐thiocyanatobenzothiazole was also detected. A mechanism is proposed to rationalize the formation of photodegradation products.
Studies with enaminonitriles: Synthesis and chemical reactivity of 2‐phenyl‐3‐piperidin‐1‐yl acrylonitrile under microwave heating
Authors: Salaheldin Abdellatif M. , Alphy Maryana K. 
Published: March 2009

Abstractmagnified imageBenzyl cyanide reacts with triethylorthoformate and piperidine in DMF solution to yield the title compound 2. This reacted with aromatic amines to yield either aminoacrylonitriles or quinoline depending on reaction conditions and substitution pattern on the aromatic amine. The reaction of compound 2 with hydrazine hydrate could only be effected in the microwave oven and resulted in the formation of aminopyrazole 7. Diazotization of 7 and coupling with an active methylene reagent afforded pyrazolo[5,1‐c]‐[1,2,4]triazine derivatives.
Synthesis of azirines containing aldehyde functionality and their utilization as synthetic tools for five membered oxazoles and isoxazoles
Authors: Brahma Sulagna , Ray Jayanta K. 
Published: March 2009

Abstractmagnified imageA simple and useful procedure for the synthesis of azirines containing aldehyde functionality from open chain bromo/chloro‐aldehydes at room temperature is reported. The scope of the ring expansion reaction of a number of 3‐substituted‐2‐formyl‐azirines has been examined using different oraganometallic catalysts and a variety of Lewis acids.
A facile synthesis of 5(6)‐(chloromethyl)benzimidazoles: Replacement of a sulfonic acid functionality by chlorine
Authors: Pete Béla , Szokol Bálint , Toőke László 
Published: March 2009

Abstractmagnified imageValuable new synthetic intermediates, 5(6)‐(chloromethyl)benzimidazoles, were prepared by the facile elimination of sulfur dioxide under the influence of thionyl chloride from benzimidazole‐5(6)‐methane‐sulfonic acids easily obtained from (3,4‐diaminophenyl)methanesulfonic acid with formic‐, or trifluoroacetic acid. Both reaction steps involved only acidic conditions, thus the synthesis of polysubstituted 5(6)‐(chloromethyl)benzimidazoles incorporating base‐sensitive substituents became possible.
Novel piperidine nitroxide derivatives: Synthesis, electrochemical and antioxidative evaluation
Authors: Zhao Hongli , Wu Juhua , Meng Xianjiang , Zuo Shaohua , Wang Wentian , Yuan Huihui , Lan Minbo 
Published: March 2009

Abstractmagnified imageNovel paramagnetic materials (3a, 3b, 4a and 4b) based on heterocyclic dyes (2a and 2b) and one stable nitroxide radical (4‐NH2‐TEMPO) were synthesized. EI‐MS, elemental analysis and FT‐IR spectral data confirmed the structures of the newly synthesized compounds. In addition, the cyclic voltammetry, the antioxidant activity and reactive oxygen species (ROS) scavenging properties of these compounds are discussed in this paper.
Synthesis of 3‐substituted indoles promoted by pulverization‐activation method catalyzed by Bi(NO3)3·5H2O
Authors: Khodaei Mohammad M. , Ghanbary Parvin , Mohammadpoor‐Baltork Iraj , Memarian Hamid R. , Khosropour Ahmad R. , Nikoofar Kobra 
Published: March 2009

Abstractmagnified imageA new, facile, efficient, “green” and chemoselective procedure for the synthesis of indole derivatives has been developed with pulverization‐activation method catalyzed by Bi(NO3)3·5H2O (PAMC‐ Bi(NO3)3·5H2O) through grinding of indoles with aldehydes or Michael acceptors in the presence of catalytic amounts of Bi(NO3)3·5H2O under solvent‐free conditions.
New straightforward route for the synthesis of some 1‐oxa‐2‐silacyclopentane derivatives
Authors: Safa Kazem D. , Shahrivar Mohammad , Tofangdarzadeh Shahin , Hassanpour Akbar 
Published: March 2009

Abstractmagnified imageTris(dimethylsilyl)methyl lithium, (HSiMe2)3CLi, reacts with allyl, phenyl, benzyl, n‐propyl and n‐butyl glycidyl ethers in THF at ‐5 °C to give 1‐oxa‐2‐silacyclopentane derivatives. It seems that ring closure is facilitated by conversion of the SiH bond into an SiO bond. Glycidyl methacrylate (GM) random copolymers with 4‐methyl‐ and 4‐methoxy styrene, synthesized by solution free radical polymerization at 70 (±1) °C with α,α‐azobis(isobutyronitrile) (AIBN) as initiator, contained pendant epoxide functions. Treatment of these with (HSiMe2)3CLi did not lead to intramolecular nucleophilic attack as found for simple epoxides.
Synthesis and molecular design of 4,8‐diaryl‐ and 4,8‐di(arylethynyl)pyrido[4,3‐d]pyrimidines: Potential applications in nonlinear optics. Diazines Part 49
Authors: Busch Alexandrine , Turck Alain , Plé Nelly 
Published: March 2009

Abstractmagnified imageUsing metallation and cross‐coupling reactions, we report the synthesis of a new series of push‐pull compounds with a pyrido[4,3‐d]pyrimidine system as the central core. Two of them were tested and their NLO properties highlighted. Incorporation of triple and double bonds as spacer between the central core and the substituted aryl groups has been performed to allow an extension of conjugation.
Macrocyclic compounds from benzenedithiols and triazine: Modification of tetrathiacalix[4]arene
Authors: Alam Ashraful , Yamaguchi Miharu , Yamamoto Tatsuya , Nakajo Shiduko , Ogawa Satoshi , Sato Ryu 
Published: March 2009

Abstractmagnified imageSynthesis of macrocyclic compounds having benzenedithionate and triazine moieties was achieved by an efficient fragment coupling approach. In the solid state, they adopted 1,3‐alternate conformations. Combination of two pairs of electron rich and electron poor units, and ortho‐ortho and/or ortho‐meta connections of sulfur atoms with aromatic carbons were novel features of the macrocycles.
Studies on the reaction of N‐(3‐carbethoxy‐4,5,6,7‐tetrahydrobenzo[b]thien‐2‐yl)‐N′‐phenylthiourea with hydrazine hydrate (Part 1)
Authors: El‐Sherief Hassan A. H. , El‐Naggar Galal M. , Hozien Zeinab A. , El‐Sawaisi Suliman M. 
Published: March 2009

Abstractmagnified imageThe reaction of N‐(3‐carbethoxy‐4,5,6,7‐tetrahydrobenzo[b]thien‐2‐yl)‐N′‐phenylthiourea (1) with hydrazine hydrate in 1‐butanol afforded a mixture of compounds 2, 3 and 4. Treatment of 3 and 4 with nitrous acid gave 6 and 8 respectively, while reactions of 3 with acetylacetone gave 7. Synthesis of tetracyclic compounds 9a‐f and 11 from the reactions of 3 with ethyl orthoformate or appropriate acids, acid chloride, carbon disulphide and/or ethyl chloroformate. Also its reaction with isothiocyanate derivatives gave the corresponding thiosemicarbzides 12a,b which on, refluxing in alcoholic KOH gave the unexpected tetracyclic products 14a,b. Similarly the tetracyclic compounds 16a‐e and 19 were obtained by cyclization of 4 and 18 respectively.
Synthesis and stereochemistry of 3‐acetyl‐5‐aminospiro[1,3,4‐thiadiazoline‐2,4′‐thioflavans]
Authors: Somogyi László , Batta Gyula , Gunda Tamás E. , Bényei Attila Cs. 
Published: March 2009

Abstractmagnified imageUnder acetylating conditions racemic thioflavanone thiosemicarbazones cyclize into racemic 3‐acetyl‐spiro[1,3,4‐thiadiazoline‐2,4′‐thioflavans] and a racemic 3‐acetylspiro[1,3,4‐oxadiazoline‐2,4′‐thioflavan] with trans O(1) or S(1) and Ph(2′eq). Hindered rotation of the endocyclic N(3) acetyl group spirothia‐diazolines caused the formation of isomers separable by HPLC. X‐ray diffraction analyses, 1H‐, 13C‐, and 15N NMR measurements as well as MOPAC QM calculations were performed to reveal the structures of these isomers.
New one step synthesis of 3,5‐disubstituted pyrazoles under microwave irradiation and classical heating
Authors: Outirite Moha , Lebrini Mounim , Lagrenée Michel , Bentiss Fouad 
Published: March 2009

Abstractmagnified imageA convenient one pot procedure for the synthesis of 3,5‐disubstituted pyrazoles by condensation of chalcones, hydrazine hydrate and sulfur in ethanol under microwave irradiation and conventional heating method is reported. The hydrogen sulfide is produced during the reaction. The pyrazoles are obtained in good yields and excellent state of purity. The structures of new compounds were confirmed by IR, 1H, and 13C NMR, MS and elemental analysis.
Synthesis of a new class of spiro heterocycles
Authors: Padmavathi Venkatapuram , Sudheer Kaveti , Subbaiah Dandu Rangayapalle Chinna Venkata , Mahesh Konda 
Published: March 2009

Abstractmagnified imageA new class of spiro heterocycles viz., spiropyrazolidinediones, isoxazolidinediones, pyrimidinetriones or thioxopyrimidinediones are developed from methyl 3‐aryl‐2‐(Z‐arylethenenylsulfonyl)acrylate by double Michael addition reaction with dimethyl malonate followed by cyclocondensation with appropriate nucleophiles.
Homolytic alkylation of some 3,4‐quinolinediyl bis‐sulfides under minisci reaction conditions
Authors: Maślankiewicz Andrzej , Michalik Ewa , Ciunik Zbigniew 
Published: March 2009

Abstractmagnified imageReaction of hydrogen sulfate of 3,4‐quinolinediyl bis‐sulfides 1a, 2a, 3a, and 4a with isopropyl and cyclohexyl radicals formed from alkyl iodide/hydrogen peroxide/DMSO/Fe++ salt system took place at α‐quinolinyl position and led to the respective mono‐ and dialkyl derivatives 1b‐e, 2b‐e, 3b,c, and 4b,c. Action of sodium methoxide towards isopropyl derivatives 1b,c and 2b,c caused the 1,4‐dithiin ring opening to form (after S‐methylation) derivatives of 3,4′‐ and 3,3′‐diquinolinyl sulfides 6a,b and 7a,b.
An efficient, “green” approach to aryl amination of cyanuric chloride using acetic acid as solvent
Authors: Kolmakov Kirill A. 
Published: March 2009

Abstractmagnified imageAcetic acid is an inexpensive and environmentally friendly solvent for facile, clean and high‐yielding aryl amination of cyanuric chloride with aromatic amines, including nitroanilines. Aryl amination in acetic acid medium and isolation protocol are greatly simplified as compared to previously reported procedures. Under proper conditions, it is possible to attach the same or different aniline residues in a controlled way to obtain in excellent yields symmetrical and unsymmetrical 1,3,5‐triazine derivatives, respectively.
4H‐1‐Benzopyrans by a tandem SN2‐SNAr reaction
Authors: Bunce Richard A. , Rogers David , Nago Takahiro , Bryant Scott A. 
Published: March 2009

Abstractmagnified imageTreatment of 2‐fluoro‐5‐nitrobenzyl bromide with active methylene compounds in the presence of excess potassium carbonate in acetone leads to the formation of highly functionalized 4H‐1‐benzopyrans by a tandem SN2‐SNAr reaction sequence. The reaction works well with β‐keto esters, β‐keto sulfones, β‐keto phosphine oxides, β‐keto phosphonates and β‐keto nitriles. The reaction is simple to perform and affords products in 50‐92% yields.
Benzo‐fused heterocycles and carbocycles by intramolecular SNAr and tandem SN2‐SNAr reactions
Authors: Bunce Richard A. , Nago Takahiro , Sonobe Nathan , Slaughter Legrande M. 
Published: March 2009

Abstractmagnified imageBenzo‐fused heterocyclic and carbocyclic systems have been synthesized by intramolecular SNAr and tandem SN2‐SNAr reactions. Treatment of 3‐(2‐fluoro‐5‐nitrophenyl)‐1‐propanol with sodium hydride in N,N‐dimethylformamide gave 6‐nitrochroman in 80% yield by an intramolecular SNAr reaction. Treatment of 2‐(3‐bromopropyl)‐1‐fluoro‐4‐nitrobenzene with benzylamine in N,N‐dimethylformamide gave 1‐benzyl‐6‐nitrotetrahydroquinoline in 98% yield by a tandem SN2‐SNAr reaction. Finally, in a similar process, reaction of this same bromide with dimethyl malonate under basic conditions gave 1,1‐bis(methoxycarbonyl)‐6‐nitro‐1,2,3,4‐tetrahydronaphthalene in 80% yield. Further studies exploring ring size effects are also presented.
Three possible products from the reactions of gewald's amide with aromatic aldehydes
Authors: Dzhavakhishvili Sergey G. , Gorobets Nikolay Yu. , Musatov Vladimir I. , Desenko Sergey M. , Paponov Boris V. 
Published: March 2009

Abstractmagnified imageTransformations of 2‐amino‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxamide (Gewald's amide) in the reactions with aromatic aldehydes were studied. Efficient methods for synthesis of three possible types of products: 2‐aryl‐5,6,7,8‐tetrahydro[1]benzothieno[2,3‐d]pyrimidin‐4(3H)‐one, 2‐(1‐arylmethylidene‐amino)‐4,5,6,7‐tetrahydrobenzo[b]thiophene‐3‐carboxamide and 2‐aryl‐2,3,5,6,7,8‐hexahydro[1]benzo‐thieno[2,3‐d]pyrimidin‐4(1H)‐one derivatives were developed. All the products were easily isolated by filtration in very good overall yields. Mutual transformations of these compounds were also studied.
Iodine catalyzed synthesis of α,α'‐bis(substituted benzylidene)‐1‐carbethoxy‐4‐piperidone
Authors: Ameen Mohame D. A. , Ahmed Essam, Kh. 
Published: March 2009

Abstractmagnified imageA facile and efficient method for the preparation of α,α′‐bis(substituted benzylidene)‐1‐carbethoxy‐4‐piperidone is described using iodine as a catalyst in acetonitrile. The reaction proceeds rapidly at room temperature, giving high yields of products.
A ‘one pot’ synthesis of 2‐aryl‐4H‐1‐benzopyran‐4‐ones under coupled microwave phase transfer catalysis (PTC) and ultrasonic irradiation PTC
Authors: Pathak Vijai N. , Varshney Bindu , Gupta Ragini 
Published: March 2009

Abstractmagnified imageA ‘one pot’ synthesis of 2‐aryl‐4H‐1‐benzopyran‐4‐ones(3a‐3f)is being reported. A mixture ofo‐hydroxyacetophenone, aroyl chloride, powderedn‐tetrabutylammonium hydrogensulphate (n‐TBAHSO4) and potassium hydroxide (KOH) were either irradiated by microwaves or sonicated in an ultrasonic cleaning bath to afford flavones directly. On the contrary, conventional liquid‐liquid Phase Transfer Catalysis (PTC) using benzene as organic phase and aqueous KOH as the second phase afforded first β‐diketones in accordance with Baker‐Venkataraman synthesis which upon cyclization byp‐toluenesulphonic acid (p‐TSA) gave desired flavones in the next step. PTC coupled with microwaves or ultrasound show enhanced yields, the clean reaction conditions require less time, and have easier workup protocol. All synthesized compounds were characterized by their Proton Magnetic Resonance (PMR), IR, FAB Mass and elemental analyses.
Synthesis of 8‐hydroxyquinolines with amino and thioalkyl functionalities at position 4
Authors: Omar Walaa A. E. , Heiskanen Juha P. , Hormi Osmo E. O. 
Published: March 2009

Abstractmagnified imageSix 8‐hydroxyquinolines with amino and thioalkyl functionalities at position 4 have been prepared. The synthesis starts with chlorination of the readily available 4‐hydroxy‐8‐tosyloxyquinoline to give 4‐chloro‐8‐tosyloxyquinoline in 94% yield. Treatment of the 4‐chloro‐8‐tosyloxyquinoline with sulphur and nitrogen nucleophiles produces the target 4‐amino and 4‐thioalkyl‐8‐hydroxyquinolines in more than 70% yield. In case of sulphur nucleophiles and pyrrolidine, the removal of the protecting tosyl group at position 8 occurs simultaneously with the substitution of chlorine at position 4.
A novel one‐pot oxidative deformylation of N‐formyldihydroquinolines employing ferric chloride hexahydrate. Synthesis of 4‐chloro‐2‐phenylquinolines and 4‐chloro‐2‐(1,3‐diphenyl‐1H‐pyrazol‐4‐yl)quinolines
Authors: Kumar Kalvi. Hemanth , Perumal Paramasivan. T. 
Published: March 2009

Abstractmagnified imageA novel versatile one‐pot oxidative deformylation approach has been developed to synthesize 4‐chloro‐2‐phenylquinolines and 4‐chloro‐2‐(1,3‐diphenyl‐1H‐pyrazol‐4‐yl)quinolines from the corresponding N‐formyldihydroquinolines.
Regioselective synthesis of N(3)‐ and O‐acylmethyl derivatives of 2‐methylthio‐4(3H)‐quinazolinone
Authors: Burbuliene Milda M. , Mazeikaite Rita , Vainilavicius Povilas 
Published: March 2009

Abstractmagnified imageReaction of 2‐methylthio‐4(3H)‐quinazolinone with chloroacetone, ω‐bromoacetophenone or ethyl bromoacetate in different solvents (methanol, acetonitrile, dimethylformamide and toluene) using sodium methoxide or potassium carbonate as a base were studied. Regioselective N(3)‐alkylation took place in toluene using potassium carbonate, whereas in dimethylformamide O‐acylmethyl derivatives were obtained. However chloroacetone reacted with 2‐methylthio‐4(3H)‐quinazolinone under various conditions to give a mixture of N(3)/O‐isomers.
Synthesis of two potential heterocyclic amine food mutagens
Authors: Tanga Mary J. , Kozocas Joseph A. , Tochimoto Todd K. 
Published: March 2009

Abstractmagnified imageThe syntheses of two potential food mutagens formed during cooking, 2‐amino‐3,6,7‐trimethyl‐3H‐imidazo[4,5‐b]pyridine (1) and 2‐amino‐3,6,7‐trimethyl‐3H‐imidazo[4,5‐c]pyridine (2), are described.
Synthesis of some 3‐aryl‐1H‐isochromene‐1‐thiones
Authors: Saeed Aamer , Ashraf Zaman 
Published: March 2009

Abstractmagnified imageA rapid microwave‐accelerated thionation of some 3‐substitued isocoumarins to corresponding 1‐thio‐isocoumarins was achieved employing Lawesson's reagent under solventless conditions.
A new, efficient and chemoselective one‐pot protocol for synthesis of 4‐arylidene‐2‐phenyl‐5(4H)‐oxazolones from aryl aldehyde bisulfite adducts promoted by POCL3
Authors: Khosropour Ahmad R. , Khodaei Mohammad M. , Jomor Seyed J. Hoseini 
Published: March 2009

Abstractmagnified imageA one‐pot procedure for the synthesis of 4‐arylidene‐2‐phenyl‐5(4H)oxazolones directly from aryl aldehyde bisulfite adducts in the absence of Ac2O in good to excellent yields using phosphoryl chloride is reported. In addition, the observed chemoselectivity can be considered as a noteworthy advantage of this method.
Cyclization of dialkylpropyn‐1‐yl(allyl)(3‐isopropenylpropyn‐2‐yl)ammonium bromides and water‐base cleavage of 2,2‐dialkyl‐5‐methyl‐2,6,7,7a‐tetrahydro‐1h‐isoindolium and 2,2‐dialkyl‐5‐methylisoindolinium bromides
Authors: Chukhajian Emma H. , Nalbandyan Martiros K. , Gevorkyan Hasmik R. , Chukhajian Eliza H. , Panosyan Henrik A. , Ayvazyan Armen G. , Tamazyan Rafael A. 
Published: March 2009

Abstractmagnified imageDialkylpropyn‐1‐yl(or allyl)(3‐isopropenylpropyn‐2‐yl)ammonium bromides under base‐catalyzed condition instantly undergo intramolecular cyclization. The cyclization of dialkylpropyn‐1‐yl(3‐isopropenylpropyn‐2‐yl)ammonium bromides leads to the formation of 2,2‐dialkyl‐5‐methylisoindolinium salts. In case of allyl analogs, instead of the expected 2,2‐dialkyl‐6‐methyl‐3a,4‐dihydroisoindolinium salts their isomeric forms ‐ 2,2‐dialkyl‐5‐methyl‐2,6,7,7a‐tetrahydro‐1H‐isoindolium bromides are obtained. In alkaline medium they are transform into the dihydroisoindolinium salts, the cleavage of which in two directions ‐ 1,2 and 1,6 leads to the mixture of isomeric dialkyl‐1,4‐dimethyl‐ and 2,4‐dimethylbenzyl‐amines.Study of the behavior of 2,2‐dialkyl‐5‐methylisoindolinium salts under conditions of water‐base cleavage showed, that only spiro[5‐methylisoindolyn]morpholinium bromide undergoes 1,2‐elimination, forming 5‐methylisoindoline 2‐vinyl ethyl ester.
Synthesis and bioactivity of 6‐bromo‐2‐(substituted)‐3‐(1‐phenyl‐ethyl)‐ 3,4‐dihydro‐1H‐ isophosphinoline 2‐chalcogenides
Authors: Srinivasulu K. , Babu B. Hari , Kumar K. Suresh , Reddy C. Bhupendra , Raju C. Naga , Rooba D. 
Published: March 2009

Abstractmagnified imageSynthesis of 6‐bromo‐2‐(substituted)‐3‐(1‐phenyl‐ethyl)‐3,4‐dihydro‐1H‐isophosphinoline 2‐chalco‐genides derivatives (6) were synthesized from 2‐[(1‐phenylethylamino)methyl]‐4‐bromophenol (1) by reaction with aryl/alkyl phosphoro dichloridates (2) in the presence of triethylamine at 55°C to 60°C to obtained the title compounds (6a‐g). The title compounds (6h‐j), were prepared via intermediate route. Few other title compounds (8a‐c) were accomplished through a two step synthetic route involving 1 with dichlorophenyl phosphine (2a) and dichloroethyl phosphine (2a,b) in the presence of triethylamine in dry toluene under N2 atmosphere to form the corresponding trivalent phosphorus intermediate (7). In the second step they were further converted to the corresponding chalcogenides 8a‐c by reaction with hydrogen peroxide, sulfur and selenium respectively. They exhibited significant antibacterial, fungal and insecticidal activity.
Studies towards the synthesis of bicyclomycin precursors: Synthesis of N,N′‐disubstituted 2,5‐diketopiperazines in solution and on solid phase
Authors: Fryszkowska Anna , Ostaszewski Ryszard 
Published: March 2009

Abstractmagnified imageThe synthesis of 3‐(hydroxyalkyl)‐N,N′‐disubstituted 2,5‐diketopiperazine derivatives ‐ compounds required for the bicyclomycin analogues preparation ‐ has been studied. The use of various oxo components in the Ugi multicomponent reaction (U‐MCR) has been evaluated. The first example of an semicyclic O,O‐acetal employed as an aldehyde equivalent in the U‐MCR has been reported. The preparation and the synthetic application of Wang resin‐bound aliphatic aldehydes in the synthesis of 2,5‐diketopiperazine skeleton has also been described.
Efficient synthesis of 5,10,15‐triarylcorroles using amberlyst 15 under solvent‐free conditions
Authors: Kumari Pratibha , Chauhan Shive M. S. 
Published: March 2009

Abstractmagnified imageAn efficient and convenient synthesis of 5,10,15‐triarylcorroles by the condensation of aryl aldehydes with pyrrole catalyzed by Amberlyst 15 followed by oxidative cyclization with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) at room temperature has been reported. Amberlyst 15 is more efficient catalyst under solvent free conditions and DDQ is more suitable oxidant in dichloromethane than those of other catalysts and oxidants, respectively, for the synthesis of corroles at room temperature.
An interesting cyclization of N‐methyl‐3‐phenyl‐N‐(2‐(Z)‐phenylethenyl)‐cis‐oxiranecarboxamide
Authors: Ma Nianchun , Wu Kemei , Huang Liang 
Published: March 2009

Abstractmagnified imageUnder Lewis acid condition, N‐methyl‐3‐phenyl‐N‐(2‐(Z)‐phenylethenyl)‐cis‐oxiranecarboxamide undergoes elegant double cyclizations to give interesting products.
Synthesis of multi‐substituted dibenzo[b,d]furan
Authors: Gajera Jitendra M. , Gopalan Balasubramanian , Yadav Pravin S. , Patil Sandip D. , Gharat Laxmikant A. 
Published: March 2009

Abstractmagnified imageThe synthesis of multi‐substituted dibenzo[b,d]furan derivatives 7a‐b and 11a‐b from readily available starting materials is described. These compounds are important intermediates for synthesis of molecules having wide therapeutic applications.