bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies with 3‐functionally substituted 2‐arylhydrazononitriles: A new route to 3‐substituted‐2‐arylhydrazononitriles, 4‐amino‐pyrazole‐5‐carbonitriles, azadienes and cinnolines
Authors: Abdel‐Motaleb Ramadan M. , Makhloof Abdel‐Moneim A. , Ibrahim Hamada M. , Elnagdi Mohamed H. 
Published: March 2009

Abstractmagnified image3‐Amino‐3‐phenyl‐2‐phenylazoacrylonitrile 6 is obtained in good yield via reaction of 5 with phenyl magnesium bromide. The compound 6 is readily converted into 4a. The so formed alkanenitrile reacted with phenylmagnesium bromide to yield 8. Compound 8 could be also obtained from reaction of 9 with phenylmagnesium bromide. The arylhydrazononitriles 8 and 4a reacted with chloroacetonitrile to yield the 4‐aminopyrazoles 12a,b. Compound 12a reacted with acetic anhydride to yield the 15a and with benzoyl chloride to yield the pyrazole 16 which was converted into 15b. Refluxing 10 in acetic acid gave a mixture of the azadiene 21 and the cinnoline 22 is obtained. The azadiene 21 is converted into 22 either thermally or photochemically.
A novel route to tetracyclic fused tetrazines and thiadiazines
Authors: Abbas Ikhlass M. , Riyadh Sayed M. , Abdallah Magda A. , Gomha Sobhy M. 
Published: March 2009

Abstractmagnified imageThe reaction between 3‐amino‐2,3‐dihydro‐7,9‐dimethyl‐2‐thioxo‐pyrido[3′,2′:4,5]thieno[3,2‐d]‐pyrimidin‐4(1H)‐one 4 or its 2‐methylthio derivative 5 with hydrazonoyl halides 6 in dioxane in the presence of triethylamine under reflux has followed heterocyclization reaction to yield pyrido[3″,2″:4′,5′]‐thieno[3′,2′:4,5]pyrimido[2,1‐c][1,2,4,5]tetrazin‐6(4H)‐ones 9. On the other hand, reaction of compound 4 with hydrazonoyl halides 6 in sodium ethoxide at room temperature led to formation of hydrazonothioate compounds 10. The latter on treatment with glacial acetic acid produced tetracyclic compounds, namely 2‐arylhydrazonopyrido[3″,2″:4′,5′]thieno [3′,2′:4,5]pyrimido[2,1‐b][1,3,4]thiadiazinones 11. An alternative method was carried out to prove the structure of product 11. The mechanism of the reaction under study was proposed and the products were screened for their biological activity.
Synthesis of novel 2‐amino‐6,8‐dithioxopurine derivatives
Authors: Ikaunieks Martins , Belyakov Sergey , Madre Marina 
Published: March 2009

Abstractmagnified imageThe synthesis of novel 2‐amino‐9‐alkoxyalkylpurine derivatives with both identical and different sulfur containing substituents at positions 6 and 8 of the purine cycle has been accomplished. The thionation and alkylation of the key intermediate ‐ 2‐[2‐(acetylamino)‐6,8‐dichloro‐9H‐purin‐9‐yl]methoxyethyl acetate or its reactions with thiolates were used. The structures of compounds obtained were confirmed by spectroscopic data and X‐ray diffraction analysis.
Azulene‐substituted pyranylium salts. Syntheses and products characterization
Authors: Razus Alexandru C. , Birzan Liviu , Pavel Claudia , Lehadus Oana , Corbu Andreea Cristina , Enache Cristian 
Published: March 2009

Abstractmagnified imageThe synthesis of 4‐azulene‐substituted 2,6‐diphenyl‐ and 2,6‐dimethyl‐pyranylium salts and 2‐azulenesubstituted 4,6‐dimethyl‐pyranylium salts by nucleophilic substitution at pyranylium moiety with various azulenes was studied. The starting materials for 2,6‐diphenyl derivatives were 4 chlorinated pyranylium salts. They were obtained by the halogenation with PCl5 of corresponding pyranones and were used either in situ or after separation. For the synthesis of dimethyl derivatives the corresponding pyranones were treated with POCl3 and the resulted intermediate was reacted in situ with azulene. In the aim to study the influence of dihedral angle between azulene and pyranylium planes on the recorded spectra, both moieties were adequately substituted. The obtained results were in accord with the calculated values.
Synthesis of novel 1‐substituted [1,3]thiazolo[3,2‐a]‐[1,5]benzodiazepine derivatives from 1,5‐benzodiazepine‐2‐thiones and α‐halogen carbonyl compounds
Authors: Janciene Regina , Stumbreviciute Zita , Podeniene Daiva , Puodziunaite Benedikta D. , Black Steve , Husbands Stephen M. 
Published: March 2009

Abstractmagnified imageA number of substituted 4H,5H,6H‐thiazolo[3,2‐a][1,5]benzodiazepinium salts 2a‐h, 5, 9, which are based on the novel thiazolobenzodiazepine system, were prepared by condensation‐cyclization of 1,5‐benzodiazepine‐2‐thiones 1a‐f, h, 4 with α‐haloketones, as well as with α‐bromoacetaldehyde diethyl acetal. The structure and stereochemistry of the ring system obtained were investigated by 1H and 13C nmr spectroscopy: the additional heterocyclic nucleus was found to appreciably influence the conformational mobility of the heptatomic ring. Upon treatment of salt 2d with alkali the presence of the base enamine structure in solution has been postulated.
One‐pot synthesis of hexahydroquinolines Via a four‐component cyclocondensation under microwave irradiation in solvent free conditions: A green chemistry strategy
Authors: Tu Shujiang , Zhang Jinpeng , Zhu Xiaotong , Zhang Yan , Wang Qian , Xu Jianing , Jiang Bo , Jia Runhong , Zhang Junyong , Shi Feng 
Published: March 2009

Abstractmagnified imageFour‐component cyclocondensation of aromatic aldehydes, malononitrile, dimedone and ammonium acetate proceeds under microwave irradiation in solvent free conditions to give highly functionalized hexahydroquinolines in excellent yields.
A clean synthesis of polyhydroacridine and indenoquinoline derivatives catalyzed by triethylbenzylammonium chloride in aqueous media
Authors: Wang Xiang‐Shan , Zhang Mei‐Mei , Zeng Zhao‐Sen , Shi Da‐Qing , Tu Shu‐Jiang , Wei Xian‐Yong , Zong Zhi‐Min 
Published: March 2009

Abstractmagnified imageAn efficient and convenient synthesis of benzo[a]acridines and indeno[1,2‐b]benzo[f]quinolines was achieved in high yields by the reaction of N‐arylidenenaphthalen‐2‐amine with 1,3‐dicarbonyl compounds catalyzed with triethylbenzylammmonium chloride (TEBAC) in aqueous media. The structures were established by spectroscopic data and further confirmed by X‐ray analysis. This method provides several advantages such as neutral conditions, high yields and simple work‐up procedure. In addition, water was chosen as a green and recyclable solvent.
Synthesis, properties and solid state structure of 5‐diphenylphosphino‐2‐hydroxy‐1,3‐xylyl‐18‐crown‐5
Authors: Corbin Rex A. , Crabill Todd W. , Storhoff Bruce N. , Huffman John C. 
Published: March 2009

Abstractmagnified image5‐Diphenylphosphino‐2‐hydroxy‐1,3‐xylyl‐18‐crown‐5 has been synthesized from 5‐bromo‐2‐hydroxy‐18‐crown‐5 by reacting it in sequence at low temperature with n‐butyl lithium and methyl diphenylphosphonite. The phosphorous donor properties of this phenol phosphine (OH derivative) and the corresponding phenoxide (O− derivative) have been studied in the presence and absence of alkali metal ions by determining the frequencies of the A1 ν(CO) bands of Ni(CO)3L complexes. For the OH and O− derivatives, the latter generated by addition of CsOH to the former, the ν(CO) bands are observed at 2067.6 and 2063.4 cm−1, respectively, providing the trend predicted by Hammett parameters for OH and O− substituents. Addition of Na+ or K+ to the OH derivative has little effect on this stretching frequency, but the former ion shifts the O− derivative band to 2067.7 cm−1 A solid state structure has been obtained of the OH derivative, and two independent molecules were found in the unit cell. Both have a single water molecule hydrogen bonded to two across‐ring oxygen atoms and the phenol hydrogen. The crown ether ring has the usual gauche and anti arrangements for the C‐C and CO bonds.
Synthesis, crystal structure of some new 2‐(4‐methylbenzoylimino)‐3‐aryl‐4‐methyl‐1,3‐thiazolines
Authors: Saeed Aamer , Parvez Masood 
Published: March 2009

Abstractmagnified imageAn efficient, straightforward synthesis of some new 2‐(4‐methylbenzoylimino)‐3‐aryl‐4‐methyl‐1,3‐thiazolines (2a‐i) is described. The methodology involves the cyclization of 1‐(4‐methylbenzoyl)‐3‐arylthioureas with acetone in the presence of bromine and triethylamine. The structures were confirmed by spectroscopic data, elemental analyses and in one case (2i) by the single crystal X‐ray diffraction data.
Condensation of some ketones with methylene active nitriles in varied stoichiometries
Authors: Fondjo Emmanuel Sopbué , Döpp Dietrich 
Published: March 2009

Abstractmagnified imageCondensations of some ketones, such as cyclopentanone, cyclohexanone, indan‐1,3‐dione, 2‐acetyl‐1‐naphthol, 1‐acetyl‐2‐naphthol, with some active methylene compounds, such as malononitrile and cyanoacetate, in the presence of amine bases, diethylamine or triethylamine, were studied. The structures of the Knoevenagel condensation products were determined by spectral analyses.
Isothiazolo[5,4‐d]isoxazole S,S‐dioxides and pyrazolo [3,4‐d]‐isothiazole S,S‐dioxides through cycloaddition reaction on 3‐benzylaminoisothiazole S,S‐dioxides
Authors: Clerici Francesca , Gelmi Maria Luisa , Monzani Cristiano , Pocar Donato , Sala Alessandro 
Published: March 2009

Abstractmagnified imageBy reacting 4,5‐unsubstituted isothiazole dioxides with diazoalkanes and nitrile oxides bicyclic pyrazolo[3,4‐d]isothiazole and isothiazolo[5,4‐d]isoxazole S,S‐dioxides were obtained in good yield through a regioselective cycloaddition reaction. Through cycloaddition reaction of 3‐benzylamino‐4‐bromo‐isothiazole S,S‐dioxide labile cycloadducts were formed that underwent in situ dehydrobromination affording the corresponding aromatized compounds.
Synthesis of imidazole and imidazolium porphyrins
Authors: Seng Virginia , Wang Xiulan , Ali Rukya , Fang Weici , Charles‐Pierre Farah , Bhagan Salome , Hyslop Alison G. 
Published: March 2009

Abstractmagnified imageA new porphyrin compound, where an imidazole group was attached through the 1‐position nitrogen to a phenyl ring located on the porphyrin periphery has been synthesized and characterized. The second nitrogen on the imidazole is available for further chemistry as demonstrated by the attachment of bromopentane forming the imidazolium porphyrin complex. This is the first example of an imidazolium group covalently attached to the porphyrin periphery in which the porphyrin is attached through the nitrogen on the imidazole ring rather than a carbon atom.
Microbial screening of novel synthesized formazans having amide linkagesΦ
Authors: Desai Krunal G. , Desai Kishor R. 
Published: March 2009

Abstractmagnified imageFormazans 5(a‐j) have been prepared by the condensation between schiff base 3 and diazonium salt of substituted 2‐amino benzothiazole 4(a‐j). The intermediate schiff base 3 was synthesized by the condensation of p‐nitrobenzolyhydrazide 1 with thiophene‐2‐aldehyde 2. All the compounds have been screened for their antifungal activity against Candida albicans (ATCC‐64550), Candida krusei (ATCC‐14243) and Candida parapsilosis (ATCC‐22019) and antibacterial activity against Escherchia coli (ATCC‐6538), Staphylococcus aureus (ATCC‐6538), Pseudomonas aeruginosa (ATCC‐1539) and Bacillus substilis (ATCC‐6633). The structures of the synthesised compounds 5(a‐j) have been characterized on the basis of their elemental analysis and spectral data (UV, IR, 1H NMR, 13C NMR and Mass).
Facile synthesis of pyrrolo[2,1‐c][1,4]benzodiazepine‐5,11‐dione dimer
Authors: Al‐Said Naim H. 
Published: March 2009

Abstractmagnified imageEfficient synthesis of biological important pyrrolo[2,1‐c][1,4]benzodiazepine‐5,11‐dione dimer linked through the C‐2 positions by fumarate group is described.
Synthetic approaches to bridgehead nitrogen methanesulfonamide derivatives of 3‐amino‐2‐thioxo‐2,3‐dihydrothieno[2,3‐d]pyrimidin‐4(1H)‐ones, potential cox‐2 selective inhibitors
Authors: Granata Giuseppe , Barbagallo Salvatore , Perdicaro Antonio , Marrazzo Agostino , Santagati Andrea , Lombardo Laura , Cardile Venera 
Published: March 2009

Abstractmagnified imageMethane sulfonamide derivatives of 3‐amino‐2‐thioxo‐2,3‐dihydrothieno[2,3‐d]pyimidin‐4(1H)‐one, potential selective COX‐2 inhibitors, were synthesized and their structural elucidation is here reported. Some derivatives, at 10 μM concentration, showed a significant percentage of inhibition in somein vitroexperiments.
Reaction of malonates with camphoranile synthesis of 4‐hydroxy‐2‐pyridones attached to the bornane ring system
Authors: Kafka Stanislav , Aigner Rudolf , Kappe Thomas 
Published: March 2009

Abstractmagnified imageThe reaction of camphoraniles 3a,b with “magic malonates” (bis‐2,4,6‐trichlorophenylmalonates) 4a,b leads to 4‐hydroxy‐2(1H)‐pyridones attached to bornane ring system 6a‐c in good yields. Less satisfactory yields were obtained with the diethyl malonate 5b. The reaction of an excess of diethyl malonate 5 itself with 3b yields the pyrono derivative 7, which can readily be degraded via the acetyl derivative 8 to the basic structure 9.
One‐pot synthesis of 2‐aminobenzothiazoles using a new reagent of [bmim]br3in [bmim]BF4
Authors: Le Zhang‐Gao , Xu Jian‐Ping , Rao Huo‐Yu , Ying Min 
Published: March 2009

Abstractmagnified imageThe one‐pot direct synthesis of 2‐aminobenzothiazoles from phenyl isothiocyanate and amines using a new reagent of 1‐butyl‐3‐methylimidazolium tribromide ([Bmim]Br3) in ionic liquid 1‐butyl‐3‐methylimidazolium tetraflouoroborate ([Bmim]BF4) is described.
Lithiation of N‐protected‐dihydro‐1,4‐benzoxaziness
Authors: Lu Yansong J. , Hu Bin , Prashad Mahavir , Kabadi Shaum , Repič Oljan , Blacklock Thomas J. 
Published: March 2009

Abstractmagnified imageLithiation of N‐protected‐2,3‐dihydro‐1,4‐benzoxazines is described. Lithiation of N‐(tert‐butoxycarbonyl)‐2,3‐dihydro‐1,4‐benzoxazine (1) with BuLi/TMEDA occurred in the α‐position to nitrogen on the heterocyclic ring, leading to the unexpected ring‐opened product 3. On the other hand, lithiation of N‐methyl‐2,3‐dihydro‐1,4‐benzoxazine (4) took place at the oxygen‐adjacent ortho‐position of the aromatic ring.
Reactions of 2‐amino‐4h‐1‐benzopyran‐4‐one with 4‐oxo‐4h‐1‐benzopyran‐3‐carbaldehydes
Authors: Ghosh Tarun , Bandyopadhyay Chandrakanta 
Published: March 2009

Abstractmagnified imageThe title aldehyde 1 reacts smoothly with the enamine moiety of 2‐aminochromone 2 to produce hitherto unreported 3‐(2‐hydroxybenzoyl)‐5H‐1‐benzopyrano[2,3‐b]pyridin‐5‐one (azaxanthone) 5. This reaction has been extended for the synthesis of bisazaxanthone 9.
Synthesis of novel quinazoline non‐nucleosides analogues of the HIV drug emivirine
Authors: El‐Brollosy Nasser R. 
Published: March 2009

Abstractmagnified imageNovel quinazoline non‐nucleosides analogues of Emivirine were described. Compounds 1a‐c were silylated and reacted with the appropriate chloroethers (2a‐c) in the presence of CsI to give the corresponding non‐nucleosides 3a‐h and 4a‐h. Silylation of 1a‐c and treatment with bis(allyloxy)methanes (5a,b) afforded the corresponding 1‐(allyloxymethyl)quinazolines 6a‐f. 1‐(Propargyloxymethyl)‐quinazolines 8a,b were obtained by treatment of the silylated 1a,b with bis(propargyloxy)methane (7) in the presence of TMS triflate.
Synthesis of 7‐azabicyclo[2.2.1]heptane derivatives by transformation of tropinone
Authors: Gómez‐Sénchez Elena , Marco‐Contelles José 
Published: March 2009

Abstractmagnified imageThe bromination (CuBr2, AcOEt/CHCI3) plus Favorskii rearrangement (EtONa, EtOH) of N‐carbethoxytropinone (4), readily available from tropinone (3), affords mixtures of exo‐ and endo‐isomers of 2,7‐dicarbethoxy‐7‐azabicyclo[2.2.1]heptane (1b) in variable and moderate chemical yield (maximum 37%). The bromination (Br2, HBr/AcOH) reaction of compound 4 gives ethyl trans‐2,4‐dibromo‐3‐oxo‐8‐azabicyclo[3.2.1]octane‐8‐carboxylate (5) in 99% yield, a product that on Favorskii rearrangement (EtONa/EtOH) affords ethyl 2,2‐diethoxy‐3‐oxo‐8‐azabicyclo[3.2.1]octane‐8‐carboxylate in moderate yield (6) (52%).
Catalyst and pressure dependent reductive cyclizations for the diastereo‐selective synthesis of hexahydropyrrolo[1,2‐a]quinoline‐5‐carboxylic esters
Authors: Bunce Richard A. , Schammerhorn James E. , Slaughter Legrande M. 
Published: March 2009

Abstractmagnified imageA diastereoselective synthesis of 1,2,3,3a,4,5‐hexahydropyrrolo[1,2‐a]quinoline‐5‐carboxylic esters has been developed using a tandem reduction‐double reductive amination reaction. The nitro dicarbonyl cyclization substrates were synthesized by alkylation of methyl (2‐nitrophenyl)acetate with 2‐bromomethyl‐1,5‐hexadiene derivatives, followed by ozonolysis. Catalytic hydrogenation of each substrate gave the target heterocycle, along with a deacylated product and an adduct resulting from capture of the intermediate hydroxylamine by the side chain carbonyls. The product ratio varied dramatically with the catalyst and the hydrogen pressure. Cyclization to the title compounds was highly diastereoselective, producing each hexahydropyrrolo[1,2‐a]‐quinoline as a single stereoisomer with the all‐cis geometry. The competing processes have not been observed in previous heterocyclization studies but can be attributed to greater strain in the system, which slows the final ring closure.
Synthesis of ethyl 6‐aryl‐4‐oxo‐4,6‐dihydro‐1(12)(13)h‐pyrimido‐[2′,1′:4,5][1,3,5]triazino[1,2‐a]benzimidazole‐3‐carboxylates
Authors: Dolzhenko Anton V. , Chui Wai‐Keung , Dolzhenko Anna V. 
Published: March 2009

Abstractmagnified imageThe synthesis of ethyl 6‐aryl‐4‐oxo‐4,6‐dihdro‐1(12)(13)H‐pyrimido[2′,1′:4,5][1,3,5]triazino[1,2‐a]‐benzimidazole‐3‐carboxylates (4a‐p) was described via pyrimidine ring annulation to 4‐aryl‐3,4‐dihydro[1,3,5]triazino[1,2‐a]benzimidazole‐2‐amines (2a‐p) which were obtained from 2‐guanidinobenzimidazole (1). Tautomerism in the prepared compounds was investigated using nmr spectroscopy. Compounds 2a‐p were found to be present in dimethyl sulfoxide solution predominantly as 3,4‐dihyhydro tautomeric form. Compounds 4a‐p existed in dynamic equilibrium of 1‐, 12‐ and 13H‐forms. It was found that methylation of 4a‐d led to 13‐methyl substituted derivatives 9a‐d exclusively.
Synthesis of 2,6‐diamino‐5‐[(2‐substituted phenylamino)ethyl]pyrimidin‐4(3h)‐one as inhibitors of folate metabolizing enzymes
Authors: Gangjee Aleem , Wang Ying , Queener Sherry F. , Kisliuk Roy L. 
Published: March 2009

Abstractmagnified imageA series of eleven novel 2,6‐diamino‐5‐[(2‐substituted phenylamino)ethyl]pyrimidin‐4(3H)‐one derivatives were synthesized as potential inhibitors of dihydrofolate reductase (DHFR) and thymidylate synthase (TS). The synthesis of analogues 2a‐f, 3a and 3e was achieved via an improved method. Commercially available anilines 12a‐f were used as starting materials which on reaction with chloroacetaldehyde followed by cyanoacetate and cyclocondensation with guanidine afforded 2,6‐diamino‐5‐[(2‐substituted phenylamino)ethyl]pyrimidin‐4(3H)‐one 2a‐f in three steps. The N‐methyl analogues 3a‐3e were prepared by reductive methylation. These compounds were evaluated against dihydrofolate reductase from Escherichia coli, Toxoplasma gondii, Pneumocystis carinii, human, and rat liver. Few compounds were marginally active against dihydrofolate reductase. The most potent inhibitor, (2c) which has a 1‐naphthyl substituent on the side chain, has an IC50 = 150 μM and 9.1 μM against Escherichia coli and Toxoplasma gondii DHFR, respectively.
Synthesis of 8,9‐dialkoxybenzodiazepines and 7,8‐dialkoxyisoquinolines
Authors: Pongó Lészló , Reiter Józef , Simig Gyula , ágai Béla , Faigl Ferenc 
Published: March 2009

Abstractmagnified imageo‐Aroylarylacetone type 1,5‐diketone derivatives (5, 6) were synthesised from arylacetones (1) protected as 1,3‐dioxolanes (4) through directed ortho lithiation followed by acylation with aroyl chlorides. 8,9‐Dialkoxy‐2,3‐benzodiazepines 9 were obtained by cyclisation of diketones 6 with hydrazine. The reaction of diketones 6 with ammonia gave 7,8‐dialkoxyisoquinolines 11. Reaction of ketals 5 with hydrazine hydrochloride and hydroxylamine hydrochloride afforded N‐amino‐7,8‐dialkoxyisoquinolinium chlorides (10) and 7,8‐dialkoxyisoquinolinium oxides (12), respectively.
Regio‐ and stereoselective synthesis of spiro[1‐benzothiepine‐4(5h), 3′(3h)‐pyrazol]‐5‐ones
Authors: Mishriky Nawal , Girgis Adel S. , Hosni Hanaa M. , Farag Hanaa 
Published: March 2009

Abstractmagnified imageReaction of (4E)‐4‐arylmethylene‐3,4‐dihydro‐1‐benzothiepin‐5(2H)‐ones 3a‐e with nitrilimines (generated in situ via triethylamine dehydrohalogenation of the corresponding hydrazonoyl chlorides 4a, b) in refluxing benzene, afforded 2′,4′,5′‐triaryl‐2,2′,3,4′‐tetrahydro‐spiro[1‐benzothiepine‐4(5H),3′(3H)‐pyrazol]‐5‐ones 5a‐i and not the isomeric forms spiro[1‐benzothiepine‐4(5H),4′(4H)‐pyrazol]‐5‐ones 6 in high regioselective manner. Single crystal X‐ray diffraction studies of 5a, f, g indicated that the isolated products are 3′R, 4′ S.
Reactivity of (2‐methylsulfanyl‐4‐oxo‐6‐phenyl‐4h‐pyrimidin‐3‐yl)‐acetic acid methyl ester towards hydrazine hydrate and benzylamine
Authors: Burbuliene Milda M. , Dobrovolskaite Rita , Vainilavicius Povilas 
Published: March 2009

Abstractmagnified imageThe title ester 1 reacted with hydrazine hydrate to give hydrazide 2, which underwent intramolecular cyclization to yield 1‐amino‐7‐phenyl‐1H‐imidazo[1,2‐a]pyrimidine‐2,5‐dione (3) or took place in a substitution reaction with benzylamine to form N‐benzyl‐2‐(2‐benzylamino‐4‐oxo‐6‐phenyl‐4H‐pyrimidin‐3‐yl)‐acetamide (4). The reaction of ester 1 with benzylamine gave corresponding amide 7, disubstituted derivative 4 or 1‐benzyl‐7‐phenyl‐1H‐imidazo[1,2‐a]pyrimidine‐2,5‐dione (8) depending on the reaction conditions.
Synthesis and tautomerization of 6,7‐dihydro‐(1,2,3)‐triazolo[1,5‐a]pyrimidines
Authors: Desenko Sergey M. , Gladkov Evgeny S. , Shishkina Svetlana V. , Shishkin Oleg V. , Komykhov Sergey A. , Orlov Valery D. , Meier Herbert 
Published: March 2009

Abstractmagnified imageThe condensation of 5‐amino‐4‐phenyl‐1,2,3‐triazole (1) with chalcones 2a‐e or 3‐dimethylamino‐propiophenone (4f) leads to the 6,7‐dihydro‐(1,2,3)‐triazolo[1,5‐a]pyrimidines 3a‐f. The equilibrium of 3 and the tautomeric 4,7‐dihydro‐(1,2,3)‐triazolo[1,5‐a]pyrimidines 3′ is described.
Synthesis and e/z determination of substituted 2‐phenylimidazoles
Authors: Szotkowski ToméŠ , Bureš Filip , Pytela Oldǐich , Kulhének Jiǐí , Trévníček Zdeněk 
Published: March 2009

Abstractmagnified imageNine new 4‐substituted 2‐phenylimidazole derivatives have been synthesized by aldol condensation of 2‐phenylimidazole‐4‐carbaldehyde with various active methylene compounds. In case of non‐symmetric active methylene compound used, the stereospecific formation of only one cis‐trans isomer has been observed. The predominant formation of products with bulkier substituents standing opposite on double bond formed by aldol condensation has been proved. cis‐trans Isomerism of three unsymmetrically substituted products has been determined by 1H coupled 13C NMR experiments. 3‐[(2‐Phenylimidazol‐4‐yl)methylene]pentane‐2,4‐dione has been characterized by single crystal X‐ray structural analysis as well. Selected bond lengths and angles have proved the expected large mesomerical stabilisation in the molecule. The hydrogen bond in crystal phase has been observed.
The synthesis of 3,3‐dimethyl‐2‐(1‐aryl‐1h‐pyrazol‐4‐yl)‐3h‐indoles
Authors: Baradarani Mehdi M. , Afghan Arash , Zebarjadi Farideh , Hasanzadeh Kamal , Joule John A. 
Published: March 2009

Abstractmagnified image2,3,3‐Trimethylindolenine and 5‐chloro‐2,3,3‐trimethylindolenine were converted into β‐diformyl compounds by the action of the Vilsmeier reagent at 50°C. The dialdehydes reacted with various arylhydrazines and 2‐pyridylhydrazine to produce mono‐hydrazones as mixtures of cis and trans isomers. Heating the hydrazones in refluxing ethanol produced 3,3‐dimethyl‐2‐(1‐aryl‐1H‐pyrazol‐4‐yl)‐3H‐indoles in excellent yields. Reaction of the β‐diformyl compounds with hydrazine itself led directly to 3,3‐dimethyl‐2‐(pyrazol‐4‐yl)‐3H‐indoles.