bluuebunny/crossref_metadata_2025_split huggingface dataset:
The synthesis of new azoniathiahelicenes
Authors: Sato Kiyoshi , Katayama Yuu , Yamagishi Takamichi , Arai Sadao 
Published: March 2009

Abstractmagnified imageSynthesis of new azonia derivatives of thia[6]helicene (1) and thia[7]helicene (2) is described. The Knoevenagel condensation of 2‐methylbenzothieno[3,2‐a]quinolizinium salt (8) with appropriate arylaldehydes yielded 2‐(arylvinyl)benzothieno[3,2‐a]quinolizinium salts (9 and 10), respectively. Photocyclization of 2‐styrylbenzothieno[3,2‐a]quinolizinium salt (8) gave 7a‐azonia‐5‐thia[6]helicene (1) in 63% yield. Similarly, 2‐[2‐(2‐naphthyl)vinyl]benzothieno[3,2‐a]quinolizinium salt (10) afforded 7a‐azonia‐5‐thia[7]helicene (2) in 56% yield. The complete and unambiguous assignment of their 1H‐ and 13C‐nmr spectra was performed by utilizing two‐dimensional nmr spectroscopic methods.
Aromatization of 1,4‐dihydropyridines in the presence of methanesulfonic acid/NaNO2/wet SiO2 under both heterogeneous and solvent free conditions
Authors: Niknam Khodabakhsh , Razavian Seyed Mehdi , Zolfigol Mohammah Ali , Mohammahpoor‐Baltork Iraj 
Published: March 2009

Abstractmagnified imageA combination of methanesulfonic acid and sodium nitrite in the presence of wet SiO2 was used as an effective oxidizing agent for the oxidation of 1,4‐dihydropyridines to the corresponding pyridine derivatives under mild and heterogeneous conditions in excellent yields.
Synthesis of 9‐[1‐benzyl‐5‐(alkylsulfonyl)‐1H‐2‐imidazolyl]perhydro‐1,8‐acridinediones
Authors: Hadizadeh F. , Mehri N. 
Published: March 2009

Abstractmagnified imageTricyclic dihydropyridines like ZM244085 are potential KATP channel openers. In this study 3‐cyanophenyl ring of ZM244085 was replaced with imidazolyl ring. So, 9‐[1‐benzyl‐5‐(alkylsulfonyl)‐1H‐2‐imidazolyl]perhydro‐1,8‐acridinediones (5d‐f) were synthesized from 2‐alkylsulfonyl‐1‐benzyl‐5‐formylimidazole (4d‐f) and cyclohexane‐1,3‐dione according to classical Hantzch synthesis as potential potassium channel modulators.
Novel 3‐benzoyl‐2‐piperazinylquinoxaline derivatives as potential antitumor agents
Authors: Piras Sandra , Loriga Mario , Carta Antonio , Paglietti Giuseppe , Paola Costi M. , Ferrari Stefania 
Published: March 2009

Abstractmagnified imageA series of new benzoylquinoxaline derivatives (7‐26) was synthesized and evaluated for antitumor activity against a panel of 60 human cell lines at the NCI of Bethesda. Among the compounds which have passed the preliminary screening, compound 23 exhibited the best profile and growth inhibition activity at 100 ‐ 10 μM. The compounds were then tested towards a folate‐dependent enzymes bio‐library including Thymidylate synthases enzymes and human Dihydrofolate reductase at 10 μM. The most of compounds exhibited a moderate inhibitory activity towards all or some of the enzymes tested with detectable inhibition constants (Ki) values in the range of 0.6‐70 μM. Compounds 21, 23, 24 showed Ki in the range of 10‐38 μM against both hDHFR and hTS.
Synthesis of oxadiazoloquinoxaline, oxathiadiazoloquinoxaline and oxadiazolobenzothiazine derivatives
Authors: Fylaktakidou Konstantina C. , Litinas Konstantinos E. , Saragliadis Athanasios , Adamopoulos Spyros G. , Nicolaides Demetrios N. 
Published: March 2009

Abstractmagnified imageBis‐amidoxime1reacts with phosgene, thiophosgene and thionylchloride to give the corresponding bisfused oxadiazolo‐ and oxathiadiazoloquinoxalines2, 4, 5along with the unexpected furazano‐derivative3, while monoamidoximes9, 13by treatment with ethyl chloroformate affords the oxadiazoloquinoxaline and the oxadiazolobenzothiazine derivatives14, 15along with the dicarboxylated product16.
A practical approach for spiro‐ and 5‐monoalkylated barbituric acids
Authors: Singh Palwinder , Paul Kamaldeep 
Published: March 2009

Abstractmagnified imageThe single step reactions of N,N′‐ substituted/‐unsubstituted barbituric acids with various alkyl dihalides under phase transfer catalytic conditions using DMF‐K2CO3 (base), TBAHSO4 (catalyst) provide spirobarbituric acids in moderate to high yields. Irrespective of the existence of C5‐monoalkylated compounds in the enolic form (confirmed by the isolation of some of its analogues), the second alkylation predominantly takes place at C5. The underlying mechanism for the reaction is discussed. The 5,7‐dimethyl‐5,7‐diaza‐spiro[2.5]octane‐4,6,8‐trione undergoes ring opening with NaCN, PhSH, HS(CH2)2OH and Br2 to provide 5‐monoalkylated barbiturates which are otherwise difficult to prepare by the usual alkylation of barbituric acids.
Tautomerism, regioisomerism, and cyclization reactions of acridinyl thiosemicarbazides
Authors: Klika Karel D. , Balentová Eva , Pihlaja Kalevi , Bernát Juraj , Imrich Ján , Vavrušová Martina , Kleinpeter Erich , Koch Andreas 
Published: March 2009

Abstractmagnified imageThe regioselectivities of methyl‐ and phenylhydrazine with acridin‐9‐yl isothiocyanate (thus yielding thiosemicarbazides with acridine substituted on the urea‐type side) were examined. Methylhydrazine regioselectivity was high with the α‐nitrogen atom overwhelmingly more nucleophilic than the β‐nitrogen atom; phenylhydrazine regioselectivity was poor but varied with the solvent and only in the case of ethanol was nucleophilic predominance of the α‐nitrogen atom pronounced. Of note, whilst both phenyl thiosemicarbazides were present in solution only as spiro forms, the methyl product was present as an equilibrium mixture of open‐chain and spiro thiosemicarbazides. Reactions on the NH2 blocked analogue of methyl acridin‐9‐ylthiosemicarbazide (1‐isopropylidene‐2‐methylthiosemicarbazide) were also examined. Interestingly, present in the starting material itself was a structural motif of novelty wherein a triazolethione represented the major species of an equilibrium between cyclic and open‐chain forms.
Anodic cyanation of 1‐arylpyrroles
Authors: Liu Wei , Ma Yuan , Zhao Yu‐Fen , Yin Ying‐Wu 
Published: March 2009

Abstractmagnified imageThe electrooxidation of several 1‐arylpyrroles has been carried out in methanol containing sodium cyanide at a platinum anode in a divided cell. In all instances, replacement of a heteroaromatic hydrogen by a cyano group occurred. On the basis of electroanalytical results, the anodic cyanation of the title compounds could be designed an EC process. As a result of two‐electron oxidation, the corresponding pyrrole cyanides were obtained in yields ranging from 76‐85%. The advantages of electrochemistry synthesis of pyrrole cyanides are simple reaction condition, low cost and high purity products.
Synthesis and characterization of a series of 1,x‐bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes
Authors: Hunter Naomi , Vaughan Keith 
Published: March 2009

Abstractmagnified imageReaction of isatoic anhydride with an alkanediamine in DMF solution under mild conditions affords excellent yields of the 1,x‐bis‐{(2‐aminobenzoyl‐)amino}alkanes (2a‐k), which have been characterized by IR and NMR spectroscopy, high resolution mass spectrometry and elemental analysis. Diazotization of the bis‐{(2‐aminobenzoyl‐)‐amino}alkanes in aqueous solution gives high yields of the 1,x‐bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes (1a‐k), whch have also been characterized by IR and NMR spectroscopy, high resolution mass spectrometry and elemental analysis. The alkanediamines employed are as follows: ethylene diamine, 1,3‐propanediamine, 1,2‐propanediamine, 2‐methyl‐1,2‐propanediamine, 2,2‐dimethyl‐1,3‐propanediamine, 2‐hydroxy‐1,3‐propanediamine, 1,4‐diaminobutane, 1,5‐diaminopentane, 1,3‐diaminopentane (DYTEK® EP diamine), 1,6‐diaminohexane and 1,7‐diaminoheptane. The alternative method of synthesis of the bis‐(4‐oxo‐3,4‐dihydro‐1,2,3‐benzotriazin‐3‐yl)alkanes (1) via the diazonium salt from methyl anthranilate was explored.
Synthesis Of 1,8‐dioxa‐dibenzo[e,h]azulenese
Authors: Pešić Dijana , Landek Ivana Ozimec , Merćaep Mladen , Mesića Milan 
Published: March 2009

Abstractmagnified imageA novel synthetic route to 2‐methyl‐1,8‐dioxa‐dibenzo[e,h]azulenes [1] via cyclisation of the corresponding 1,4‐dicarbonyl compound is described. 1,4‐Dicarbonyl compounds were synthesized by the alkylation reaction of the 11H‐dibenzo[b,f]oxepine‐10‐one while analogous alkylation of 11H‐dibenzo[b,f]thiepine‐10‐one resulted in formation of O‐alkylated products. Selective oxidation of 2‐methyl group afforded 1,8‐dioxa‐dibenzo[e,h]azulenes with formyl and hydroxymethyl functionality at C(2) position.
An efficient synthesis of benzo[b][1,8]naphthyridine‐3‐carboxylic methyl esters
Authors: Nithyadevi V. , Rajendran S. P. 
Published: March 2009

Abstractmagnified imageMethyl‐3‐(2‐chloroquinolin‐3‐yl)acrylates 5a‐i on reaction with methyl amine in acetonitrile yielded methyl‐3‐[2‐(methylamino)quinolin‐3‐yl]acrylates 6a‐i. When, these were followed by the reaction with the Vilsmeier reagent, they afforded methyl benzo[b][1,8]naphthyridin‐3‐carboxylate 7a‐i in good yields.
Cyclocondensation reactions of heterocyclic carbonyl compounds XII. The double course of cyclization of 3‐(2‐aminobenzyl)‐1,2‐dihydro‐quinoxaline‐2‐one
Authors: Fryšová Iveta , Slouka Jan , Hlaváč Jan , Lyčka Antonńan 
Published: March 2009

Abstractmagnified imageThe cyclocondensation reaction of compound 1 in boiling hydrochloric acid had an unexpected course. Instead of supposed 5,11‐dihydro‐quinoxalino[2,3‐b]quinoline 6a, 2‐(indol‐2‐yl)‐benzimidazole 4 was isolated as the major product.
Ruthenium‐catalyzed biginelli condensation: A simple and efficient one‐pot synthesis of 3,4‐dihydropyrimidin‐2(1H)‐ones under mild reaction conditions
Authors: Jain Suman L. , Sharma Vishal B. , Sain Bir 
Published: March 2009

Abstractmagnified imageRuthenium trichloride was found to be an efficient catalyst for the first time for the synthesis of a variety of 3,4‐dihydropyrimidin‐2(1H)‐ones by cyclocondensation of an aldehyde, β‐dicarbonyl compound and urea in excellent yields under mild reaction conditions.
One‐Pot stereoselective synthesis of trans‐4,5‐dialkoxy‐1,3‐bis (2‐pyrimidinyl)imidazolidines through a three‐component reaction
Authors: Ghandi Mehdi , Salimi Farshid , Olyaei Abolfazl 
Published: March 2009

Abstractmagnified imageStoichiometric reaction of 2‐aminopyrimidine with formaldehyde in the presence of formic acid catalyst in water gave N,N′‐bis(2‐pyrimidinyl)methanediamine (5). Subsequent cyclocondensation of 5 with glyoxal in alcohol (MeOH, EtOH, PrOH and i‐PrOH) under reflux conditions led to the formation of the corresponding 4,5‐dialkoxy‐1,3‐bis(2‐pyrimidinyl)imidazolidines (6a‐d). 4,5‐Dihydroxy‐1,3‐bis(2‐pyrimidinyl) imidazolidine (6e) was obtained when the reaction was carried out in acetonitrile. Based on 1H NMR analysis, it was found that the trans‐dialkoxyimidazolidines (6) were selectively obtained in these cyclocondensation reactions.
A facile synthesis of 2‐substituted thieno[3′,2′‐5,6]‐pyrido[4,3‐d]pyrimidin‐4(3H)‐ones
Authors: Liu Jian‐Chao , He Hong‐Wu , Ren Qing‐Yun , Ding Ming‐Wu 
Published: March 2009

Abstractmagnified imageThe thienopyridine derivative 2, obtained from reaction of acetoacetic ester with 1 in the presence of tin tetrachloride, was treated with triphenylphosphine in hexachloroethane and Et3N to give iminophosphorane 3. Iminophosphorane 3 reacted with phenyl isocyanate to give carbodiimide 4, which was further treated with phenols or ethenol to produce 2‐substituted 5,8,9‐trimethyl‐3‐phenyl‐thieno[3′,2′‐5,6]pyrido[4,3‐d]pyrimidin‐4(3H)‐ones 5 in presence of catalytic amount of K2CO3 or EtONa. The structures of compounds 5 were confirmed by 1H NMR, IR, MS, and elemental analysis.
Reaction of 4‐substituted thiosemicarbazides with (2,4,7‐trinitro‐9H‐fluoren‐9‐ylidene)propanedinitrile
Authors: Hassan Alaa A. , Ibrahim Yusria R. , Shawky Ahmed M. , Döpp Dietrich 
Published: March 2009

Abstractmagnified image4‐Substituted thiosemicarbazides4a‐creacted with (2,4,7‐trinitro‐9H‐fluoren‐9‐ylidene)‐propanedinitrile (2) in pyridine with admission of air to form spiro[fluorene‐9,3′‐(1,2,4‐triazole)]derivatives5a‐cand (4‐substituted thiosemicarbazono)propanedinitriles6a‐cin modest yields. 2,4,7‐Trinitro‐9‐fluorenone (8) as well as one reduction product thereof and of2, namely compounds9and10, respectively are also found. A rationale for the conversions observed is presented.
Synthesis and biological activity of novel 1‐(2,3,4‐trimethoxyphenyl)‐2‐{[5‐(3,4,5‐trimethoxyphenyl)‐1,3,4‐thiadiazol‐2‐yl]thio}ethanone oxime ester derivatives
Authors: Xue Wei , Song Baoan , He Wei , Wang Hua , Yang Song , Jin Linhong , Hu Deyu , Liu Gang , Lu Ping 
Published: March 2009

Abstractmagnified imageIn a search for new fungicide and anticancer agent with improved biological properties and different bioactivity spectrum, we designed and synthesized a series of novel oxime esters containing 1,3,4‐thiadiazole group in moderate yield starting from gallic acid. The title compounds were identified by IR, 1H NMR, 13C NMR and elemental analysis. The bioassay tests showed that these title compounds exhibit weak to moderate anticancer activity in vitro by MTT method.
Microwave induced synthesis of the thiazolidine‐2,4‐dione motif and the efficient solvent free‐solid phase parallel syntheses of 5‐benzylidene‐thiazolidine‐2,4‐dione and 5‐benzylidene‐2‐thioxo‐thiazolidine‐4‐one compounds
Authors: Kumar B. R. Prashantha , Nanjan M. J. , Suresh B. , Karvekar M. D. , Adhikary L. 
Published: March 2009

Abstractmagnified imageNovel microwave induced method for the synthesis of thiazolidine‐2,4‐dione motif under solvent phase conditions is developed. Further we report an efficient, microwave assisted method for the parallel syntheses of biologically important 5‐benzylidene‐thiazolidine‐2,4‐dione and 5‐benzylidene‐2‐thioxothiazolidine‐4‐one compounds under solid‐phase and solvent‐free conditions. A comparative study between the developed microwave methods and the conventional methods is described. We have also illustrated the possible mechanism behind to address the reason why piperidine, acetic acid and silica gel enhanced the Knoevenagel condensation reaction.
Synthesis, structure and biological activities of [α‐(alkylcarbonyl)‐2‐(1,2,4‐triazol‐1‐yl)]ethyl‐N,N‐dialkydithiocarbamate derivatives
Authors: Jian Fangfang , Xiao Hailian , Zhu Chongyi , Xu Liangzhong 
Published: March 2009

Abstractmagnified imageSeven 1,2,4‐triazole compounds containing the N,N‐dialkyldithiocarbamate group were designed and synthesized. Their structures were identified using infrared spectroscopy, element analysis, 1H NMR spectroscopy and mass spectrometry, and in two cases by single crystal X‐ray diffraction. The result of the biological test showed that the seven compounds all have fungicidal and plant growth‐regulating activities.
Behavior of 3‐benzylamino‐5‐aryl‐2(3H)‐furanones towards some nitrogen nucleophiles
Authors: Kandeel Kamal A. , Youssef Ahmed S. A. , Abou‐Elmagd Wael S. I. , Hashem Ahmed I. 
Published: March 2009

Abstractmagnified imageRing closure of 2‐N‐benzylamino‐3‐aroylpropionic acids (3) with acetic anhydride afforded 3‐N‐benzylamino‐5‐aryl‐2(3H)‐furanones (4). The reaction of the furanones (4) with benzylamine in benzene was found to be time dependent. Thus refluxing the reaction mixture for 1 h only afforded the open‐chain amides (5a‐c). When the reaction was conducted for 3 h the 2(3H)‐pyrrolones (6) were obtained. Hydrazine hydrate affected ring opening of the furanones to give the hydrazides (5d‐f). Also, semicarbazide converted (4) into the corresponding semicarbazide derivatives (5g‐i). The hydrazides (5d‐f) were reacted with benzoyl chloride to give the corresponding diaroylhydrazines (5j‐l). The open‐chain derivatives (5) were converted into a variety of heterocycles: isothiazolones (7), dihydropyridazinones (8), 1,3,4‐oxadiazoles (9) and 1,2,4‐triazole derivatives (10) via cyclization reactions.
The reaction of aryl and heteroarylhydrazines with aryl‐trifluoromethyl β‐diketones
Authors: Singh Shiv P. , Kumar Vinod , Aggarwal Ranjana , Elguero Jose 
Published: March 2009

Abstractmagnified imageWe report the results obtained when five aromatic or heteroaromatic hydrazines react with six β‐diketones bearing trifluoromethyl and aryl substituents. Forty‐two compounds have been isolated corresponding to two isomeric trifluoromethyl pyrazoles and the intermediate 5‐CF3, 5‐OH pyrazolines. The results have provided useful information for establishing the mechanism of the synthesis of pyrazoles.
Dibenzo‐fused seven‐membered nitrogen heterocycles by a tandem reduction‐lactamization reaction
Authors: Bunce Richard A. , Schammerhorn James E. 
Published: March 2009

Abstractmagnified imageEfficient syntheses of dibenz[b,f][1,4]oxazepin‐11(10H)‐one, 5,10‐dihydro‐11H‐dibenzo[b,e][1,4]‐diazepin‐11‐one and 5,11‐dihydro‐6H‐dibenz[b,e]azepin‐6‐one are described using a tandem reductionlactamization sequence. Precursors for these ring systems are available in 1‐3 steps using nucleophilic aromatic substitution and Ullmann coupling methodology. Direct reduction‐lactamization of these compounds using iron powder in acetic acid at 115° affords the target heterocycles in ≥90% yield.
Synthesis of new heteroaromatic nitrogen ligands: Pyrimido‐[4″,5″:4′,5′]‐thieno[3′,2′:4,5]thieno[3,2‐d]pyrimidines and 1,2,3‐triazine[4″,5″:4′,5′]thieno[3′,2′:4,5]thieno[3,2‐d]‐1,2,3‐triazines
Authors: Blanco Gerardo , Quintela José M. , Peinador Carlos 
Published: March 2009

Abstractmagnified imageAn efficient one‐pot access for the synthesis of the previously unreported tetracyclic fused pyrimido‐[4″,5″:4′,5′]thieno[3′,2′:4,5]thieno[3,2‐d]pyrimidine (3) and 1,2,3‐triazine[4″,5″:4′,5′]thieno‐[3′,2′:4,5]thieno‐[3,2‐d]‐1,2,3‐triazine (5) heteroaromatic nitrogen ligands is described. The title compounds 3 and 5 were obtained from 3,4‐diaminothieno[2,3‐b]thiophene‐2,5‐dicarbonitrile and phosgeniminium chloride and sodium nitrite/HCl, respectively. Substituted condensed thieno[2,3‐b]thiophene derivatives 4 and 6 were synthesized by nucleophilic displacement of the chloroderivatives 3 and 5.
Synthesis of N‐amino‐3‐hydroxy‐2‐phenyl‐4(1H)‐quinolinone
Authors: Spáčilová Lucie , Hlaváč Jan , Hradil Pavel , Fryšová Iveta , Soural Miroslav , Krejčí Petr , Maloň Michal 
Published: March 2009

Abstractmagnified image2‐[(Disubstituted‐methylene)‐hydrazino] benzoic acid phenacylesters 2a‐2d, prepared from anthranilic acid phenacylester 1, were unsuccesfully tried as starting materials for the synthesis of N‐amino‐3‐hydroxy‐2‐phenyl‐4(1H)‐quinolinone 8. The desired compound 8 was prepared by cyclization of N‐acetyl as well as N‐benzoyl‐hydrazinobenzoic acid phenacylester 6a or 6b in polyphosphoric acid to afford N‐acylamino‐3‐hydroxy‐2‐phenyl‐4(1H)‐quinolinone 7a or 7b, respectively. Surprisingly, the acyl group was resistant to attack by both hydrochloric acid as well as sodium hydroxide solution. It could be removed by boiling the compounds 7a or 7b respectively in 50% sulphuric acid to afford the the target compound 8.
Study of the pyrimidine nucleobase C5C6 bond reactivity under thio‐michael/aldol tandem reaction conditions
Authors: Velez Edna Vázquez , Desnous Céline , Clivio Pascale 
Published: March 2009

Abstractmagnified imagePyrimidine nucleobases can undergo a Michael/aldol tandem reaction triggered by a thiolate. In an intramolecular context, 5′‐deoxy‐2′,3′‐isopropylidene‐5′‐thiouridine affords the reminiscent Baylis‐Hillman adduct after retro‐Michael addition whereas its thymine counterpart is unreactive. In an intermolecular context, the conjugate addition‐aldol reaction occurs only if the C5C6 double bond is activated.
Synthesis of new peptide nucleic acid monomer with glycylglycine backbone
Authors: Yamasaki Tetsuo , Watanabe Akiko , Sakamoto Masanori , Otsuka Masami , Abdel‐Aziz Mohamed , Iwashita Takashi 
Published: March 2009

Abstractmagnified imageNew thymine peptide nucleic acid (PNA) monomer with glycylglycine backbone was prepared. This involved a key step of the coupling between iodinated serine (3) and 3‐benzoylthymine.
Formation of pyridazino[4,5‐c]pyridazine derivatives upon [4+2]cycloaddition of 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione to cross‐conjugated monoferrocenyltrienes
Authors: Martínezmendoza Juan M. , Vázquez López Eduardo A. , Esparza Rafael Moreno , Alamo Marcos Flores , Klimova Elena I. 
Published: March 2009

Abstractmagnified imageCross‐conjugated monoferrocenyltrienes react with 4‐phenyl‐1,2,4‐triazoline‐3,5‐dione to give mono‐ and bis‐[4+2]‐cycloaddition products. Nonsubstituted and 2,4‐disubstituted 3‐ferrocenylmethylidenepenta‐1,4‐dienes afford respective pyridazine and pyridazino[4,5‐c]pyridazine derivatives. Their structures were established based on1H and13C NMR data and X‐ray diffraction analysis.
A facile synthesis of some substituted furopyrimidine derivatives
Authors: Pyo Jung In , Lee So Ha , Cheong Chan Seong 
Published: March 2009

AbstractSome substituted furopyrimidine derivatives are prepared in high yield in 4 steps, starting from the reaction of furoin (1,2‐di(furan‐2‐yl)‐2‐hydroxyethanone) and malonitrile.
Synthesis and alkylation of 5‐(3‐chlorobenzo[b]thien‐2‐yl)‐4H‐1,2,4‐triazole‐3‐thiol under classical and microwave conditions. AM1 semiemperical calculations for investigating the regioselectivity of alkylation
Authors: Ashry E. S. H. El , Kassem A. A. , Abdel‐Hamid H. , Louis F. F. , Khattab S. H. A. N. , Aouad M. R. 
Published: March 2009

Abstractmagnified imageUnder microwave irradiation (MWI), 5‐(3‐chlorobenzo[b]thien‐2‐yl)‐4H‐1,2,4‐triazole‐3‐thiol (3) was synthesized in a good yield by intramolecular cyclization of the carbonyl thiosemicarbazide 2. A regioselective S‐alkylation of 3 with benzyl chloride or allyl bromide has been achieved by using triethylamine as a base, while other different basic conditions led to a mixture of bis(alkylated) derivatives N4, S‐ and S, N2‐, under both of classical and MWI conditions. The relative stabilities, charge densities, dipole moments and electronic energies of reactants, transition states and intermediates were calculated by the AM1 method and used for investigating the regioselectivity.
Thermal decomposition reactions of n‐alkylated 2‐aminobiphenyls to carbazole and phenanthridine
Authors: Creencia Evelyn Cuevas , Horaguchi Takaaki 
Published: March 2009

Abstractmagnified imageThermal cyclization reactions were examined by passing vapors of N‐alkylated 2‐aminobiphenyls 1a‐c and 2 over calcium oxide at 450‐600°C under nitrogen carrier gas. The reactions yielded 9‐methylcarbazole 3, carbazole 4, phenanthridine 5 and phenanthrene 6. The major product for the reactions of 1a, 1b and 2 was phenanthridine 5 while that of 1c was carbazole 4.
Synthetic studies connected with the preparation of h+/k+‐ATPase inhibitors rabeprazole and lansoprazole
Authors: Rédl Stanislav , Klecén Ondřej , Havlíček Jaroslav 
Published: March 2009

Abstractmagnified imageSynthesis of lansoprazole and rabeprazole using common intermediates is devised. The common intermediates, 2‐[(4‐nitro‐3‐methylpyridin‐2‐yl)methanesulfanyl]‐1H‐benzoimidazole and 2‐[(4‐chloro‐3‐methyl‐pyridin‐2‐yl)methanesulfanyl]‐1H‐benzoimidazole, were prepared in several ways.
One‐pot synthesis of 2‐acylimino‐3‐aryl‐1,3‐thiazoline derivatives in aqueous media
Authors: Wang Xi Cun , Wang Fang , Quan Zheng Jun , Zhang Zhang , Wang Man Gang 
Published: March 2009

Abstractmagnified imageThe one‐pot two‐step synthesis for acyliminothiazolines by treatment of N,N'‐substituted thioureas with α‐bromocarbonyl compounds under aqueous media was described. Compared to classical reaction in organic solvents, this method consistently has the advantages of short reaction time and being environmentally friendly.