bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of 3‐(2‐hydroxy‐1‐phenylethyl)‐ and 3‐(2‐hydroxy‐2‐phenylethyl)adenine, DNA adducts derived from styrene
Authors: Krouželka Jan , Linhart Igor , Tobrman Tomáš
Published: March 2009

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3‐(2‐Hydroxy‐2‐phenylethyl)‐ and 3‐(2‐hydroxy‐1‐phenylethyl)adenine, DNA adducts derived from styrene, along with their 9‐substituted analogues were prepared by alkylation of 8‐bromoadenine with corresponding allyl‐protected bromohydrins followed by a new deallylation procedure using tetrakis(triphenylphosphine)palladium catalyzed reductive cleavage by poly(methylhydrosiloxane) in the presence of p‐toluenesulphonic acid. This novel procedure proved to be useful for purine derivatives, which were resistant to other deallylation protocols. Structure of positional isomers was assigned using 2D NMR experiments HMBC and HMQC.
Thermal reactions of N‐alkyl‐2‐benzylaniline and N‐alkyl‐N′‐phenyl‐o‐phenylenediamine: An unusual route to 2‐phenylindole and 2‐phenylbenzimidazole
Authors: Creencia Evelyn Cuevas , Taguchi Kei , Horaguchi Takaaki
Published: March 2009

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Thermal cyclization reactions of N‐alkyl‐2‐benzylaniline 1a‐d and N‐alkyl‐N′‐phenyl‐o‐phenylenediamine 2a‐b were carried out expecting to get seven‐membered heterocyclic compounds. However, the results show that aside from the formation of the normally expected six‐membered ring products of acridine 5, anthracene 6, and phenazine 8, thermal cyclization of N‐alkyl‐2‐benzylaniline and N‐alkyl‐N′‐phenyl‐o‐phenylenediamine also resulted to the unexpected formation of 2‐phenylindole 3 and 2,3‐diphenylindole 4, and 2‐phenylbenzimidazole 7, respectively.
The cycloacylation — 1,3‐Acylrearrangement sequence as tool for highly substituted pyrrolones
Authors: Buehrdel Gunther , Beckert Rainer , Friedrich Birgit , Goerls Helmar
Published: March 2009

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The cyclization reactions between bis‐imidoylchlorides 1 and ketones, which possess different CH‐acidity, were investigated. Diphenylacetone 2 reacts under mild conditions via C,O‐cyclization of the preformed enolate to yield the iminofurane derivative 3. Upon treatment with trifluoroacetic acid, the latter can be rearranged quantitatively into the pyrrolone 5. In contrast, 1,3‐acetonedicarboxylate 9 and cyclohexanone 12 immediately lead to highly substituted pyrrolones 11 and 14. Obviously, the primarily formed cyclization products undergo a very fast 1,3‐acyl rearrangement (Dimroth‐/Mumm‐Rearrangement). The structures of the maleiimide 11 and the indolone 14 were determined by single crystal X‐ray structure analysis. Due to its amino/imino substructure, compound 3 is an efficient ligand for metal complexation reactions, exemplified by the synthesis of two different Zn‐complexes 7 and 8.
Salicylaldehyde based oxazolidines as catalysts for the asymmetric addition of diethylzinc to aldehydes
Authors: Parrott Raleigh W. , Hamaker Christopher G. , Hitchcock Shawn R.
Published: March 2009

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A series of oxazolidines have been prepared by condensation of N‐isopropyl norephedrine with a variety of salicylaldehyde derivatives. Despite the stereochemical relationship of (1R,2S)‐norephedrine with (1R,2S)‐ephedrine, the resultant oxazolidines 12‐14 were determined to have a stronger stereochemical relationship with (1S,2S)‐pseudoephedrine based oxazolidines. The resultant oxazolidines were used as catalytic ligands in the addition of diethylzinc to several aldehydes. It was determined that the oxazolidine derivative 12 gave the highest yield and a moderate enantioselectivity.
New synthetic route towards 2,2‐dimethylchromene and synthesis of substituted 7‐(dimethylpropargyl)chromene
Authors: Alizadeh Babak H. , Foroumadi Alireza , Shafiee Abass
Published: March 2009

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Trifluoromethansufonic acid (TFA) was found a proper reagent for regioselectively ring closure of resorcinol to afford 7‐hydroxy‐2,2‐dimethyl‐2,3‐dihydrochromen‐4‐one 3. The propargylation of 3 gave rise to 2,2‐dimethyl‐7‐(2‐methylbut‐3‐yn‐2‐yloxy)‐2,3‐dihydrochromen‐4‐one 4. Condensation of 4 with substituted phenyl or benzyl Grignard reagents afforded substituted phenyl or benzylidene chromenes 6a‐d and 4‐(substitutedbenzylidene)‐3,4‐dihydro chromenes 8a‐e, respectively.
An efficient preparation of new homoallylamines and α‐aminonitriles bearing furyl and thienyl rings
Authors: Méndez Leonor Y. Vargas , Kouznetsov Vladimir V.
Published: March 2009

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New diverse N‐aryl‐N‐[1‐furyl(thienyl)but‐3‐enyl]amines (homoallylamines) or 2‐(N‐arylmethylamino)‐2‐furyl(thienyl)acetonitriles (α‐aminonitriles) were easily prepared in good to excellent yields by an indium‐mediated Barbier‐type reaction between N‐hetarylaldimines and allyl bromide in MeOH or a direct three component reaction between anilines, hetaryl aldehydes and trimethylsilyl cyanide in the presence of a catalytic amount of molecular iodine at room temperature, respectively. The entire set of amines was characterized by IR, 1H and 13C NMR spectroscopy.
A simple procedure for the synthesis of benzoxanthene derivatives under microwave irradiation conditions
Authors: Chen Yan , Wu Shanshan , Tu Shujiang , Li Chunmei , Shi Feng
Published: March 2009

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A rapid and efficient method is developed to synthesize a series of benzoxanthene derivatives by the reaction of aldehydes and 2‐hydroxynaphthalene‐1,4‐dione in mixed solvent of acetic acid and ethylene glycol under microwave irradiation. The method has the advantages of short synthetic route, operational simplicity and higher yields (70%∼85%).
Dodecyloxy‐substituted 2,4,6‐tris(styryl)pyridines
Authors: Lifka Thorsten , Oehlhof Annette , Meier Herbert
Published: March 2009

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(E,E,E)‐2,4,6‐Tris(styryl)pyridines 2a‐c with 3, 6 or 9 dodecyloxy substituents were prepared by the highly stereoselective condensation reaction of collidine (8) and the corresponding phenyl‐(1‐phenyl‐methylidene)amines 7a‐c (Siegrist reaction). In contrast to the corresponding compounds with a benzene or a 1,3,5‐triazine core, 2a‐c do not show any hints for the formation of thermotropic liquid crystals. The major application of such star‐shaped systems is in the field of nonlinear optics.
Progress in the chemistry of 4‐ thiazolidinones
Authors: Hamama Wafaa S. , Ismail Mohamed A. , Shaaban Saad , Zoorob Hanafi H.
Published: March 2009

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This review article includes a recent development in the chemistry of 4‐thiazolidinones. Structure, basicity, synthetic aspects, reactions, and applications were also reported.
Regio‐ and stereoselective synthesis of isoxazolidine derivatives by asymmetric 1,3‐dipolar cycloaddition reaction of chiral nitrones with 1‐propene‐1,3‐sultone
Authors: Zhang Hong‐Kui , Chan Wing‐Hong , Leeb Albert W. M. , Wong Wai‐Yeung
Published: March 2009

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Asymmetric 1,3‐dipolar cycloadditions of chiral nitrones to 1‐propene‐1,3‐sultone (1) were investigated. Chiral nitrones 6a‐e reacted with sultone 1 in toluene at 90 °C for 24‐36 h to give the corresponding isoxazolidines in moderate yields with high regioselectivities and stereoselectivities. The diastereoselectivity of this reaction varied with the choice of dipolarophile and the steric demands of nitrones. When sultone 1 was allowed to react chiral nitrone 6e, a much better diastereoselectivity of up to 5.1:1 was observed.
Photocyclisations of some 3‐alkoxy‐2‐thienylchromones
Authors: Yusuf Mohamad , Kumar Rupesh , Gupta S. C.
Published: March 2009

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Photoreorganisations of some 3‐allyloxy‐2‐thienylchromones have been described. The photoreactions are initiated through the intramolecular H‐abstraction to provide angular tetracyclic compounds. These chromones yield good chemical efficiency due to the involvement of highly stabilized allylic 1,4‐biradicals.
N‐[(Diphenoxyphosphoryl)oxy]‐2‐phenyl‐1H‐benzimidazole as a versatile reagent for synthesis O‐alkylhydroxamic acids
Authors: Kokare Nagnnath D. , Shinde Devanand B.
Published: March 2009

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Highly efficient reagent, N‐[(diphenoxyphosphoryl)oxy]‐2‐phenyl‐1H‐benzimidazole was synthesized and its applicability was demonstrated for the synthesis of O‐alkyl hydroxamic acids. The efficiency of the reagent was evaluated through the synthesis of range of O‐alkyl hydroxamic acids from aromatic carboxylic acids as well as N‐protected amino acids. The enatiomeric purity of synthesized compounds was measured using chiral HPLC and the degree of racemization that occurred was found to be negligible.
Preparation of derivatives of 1‐(2‐pyrimidinyl)piperazine as potential antianxiety, antidepressant, and antipsychotic agents
Authors: Becker Irwin
Published: March 2009

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This paper describes the preparation of twenty‐eight derivatives of 1‐(2‐pyrimidinyl)piperazine as potential antianxiety, antidepressant, and antipsychotic agents. In twenty‐six of the preparations a chloro nitrogen heterocycle was caused to react with an excess of 1‐(2‐pyrimidinyl)piperazine in the absence of solvent. A specific example is given above.
Synthesis of some novel pyrazolo[1,5‐a]pyrimidine, 1,2,4‐triazolo[1,5‐a]pyrimidine, pyrido[2,3‐d]pyrimidine, pyrazolo[5,1‐c]‐1,2,4‐triazine and 1,2,4‐triazolo[5,1‐c]‐1,2,4‐triazine derivatives incorporating a thiazolo[3,2‐a]benzimidazole moiety
Authors: Abdel‐Aziz Hatem A. , Hamdy Nehal A. , Fakhr Issa M. I. , Farag Ahmad M.
Published: March 2009

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E‐3‐(N,N‐Dimethylamino)‐1‐(3‐methylthiazolo[3,2‐a]benzimidazol‐2‐yl)prop‐2‐en‐1‐one (2) was synthesized by the reaction of 1‐(3‐methylthiazolo[3,2‐a]benzimidazol‐2‐yl)ethanone (1) with dimethylformamide‐dimethylacetal. The reaction of2with 5‐amino‐3‐phenyl‐1H‐pyrazole (4a) or 3‐amino‐1,2,4‐(1H)‐triazole (4b) furnished pyrazolo[1,5‐a]pyrimidine and 1,2,4‐triazolo[1,5‐a]pyrimidine derivatives6aand6b, while the reaction of enaminone2with 6‐aminopyrimidine derivatives7a,bafforded pyrido[2,3‐d]pyrimidine derivatives9a,b, respectively. The diazonium salts11aor11bcoupled with compound2to yield the pyrazolo[5,1‐c]‐1,2,4‐triazine and 1,2,4‐triazolo[5,1‐c]‐1,2,4‐triazine derivatives13aand13b. Some of the newly synthesized compounds exhibited a moderate effect against some bacterial and fungal species.
Regioselective synthesis of heterocyclic scaffold by aryl radical cyclization
Authors: Majumdar K. C. , Kundu N.
Published: March 2009

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Regioselective synthesis of a number of coumarin‐annulated pentacyclic heterocycles have been achieved by tri‐n‐butyltin hydride‐mediated aryl radical cyclization. The products are formed as a mixture of cis‐ and trans‐ forms which were successfully separated by careful silica gel flash chromatography.
Synthesis of some oxazolyl ‐ pyrazolyl; 1,4‐Dihydropyridinyl‐pyrazolyl and 1,2,3,4‐tetrahydro pyrimidinyl‐pyrazolyl coumarins
Authors: Patel Mehul A. , Brahmbhatt Dinker I.
Published: March 2009

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Various 3‐[1‐phenyl‐4‐(2‐substituted‐5‐oxo‐oxazol‐4‐ylidenemethyl) pyrazol‐3‐yl] coumarins 4a‐f; 3‐[1‐phenyl‐4‐(2,6‐dimethyl‐3,5‐disubstituted‐1,4‐dihydropyridin‐4‐yl) pyrazol‐3‐yl] coumarins 5a‐f and 3‐[1‐phenyl‐4‐(6‐methyl‐5‐substituted‐2‐oxo‐1,2,3,4‐tetrahydropyrimidin‐4‐yl) pyrazol‐3‐yl] coumarins 6a‐f have been synthesized utilizing Erlenmyer‐Plochl reaction, Hantzsch reaction and Biginelli reaction respectively using 3‐(1‐phenyl‐4‐formyl‐pyrazol‐3‐yl) coumarins 3a‐c as a starting material.
Ketene dithioacetals‐source for different heterocycles
Authors: Padmavathi Venkatapuram , Reddy Gali Sudhakar , Deepti Duvvuru , Padmaja Adivireddy
Published: March 2009

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Some pyrazoline, isoxazoline and pyrimidine derivatives were synthesized from ketene dithioacetals using appropriate nucleophiles.
A convenient synthesis of novel 1,3,4‐triaryl‐3,4‐dihydropyrimidin‐2(1H)‐ones by cyclization of aromatic isocyanates with β‐arylamino‐1‐phenylpropan‐1‐ones
Authors: Hu Yongzhou , Lu Xiuyang , Xue Na
Published: March 2009

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A simple one‐step method for preparation of novel 1,3,4‐triaryl‐3,4‐dihydropyrimidin‐2(1H)‐ones has been developed by reaction of aromatic isocyanates with β‐arylamino‐1‐phenylpropan‐1‐ones in refluxing toluene in the presence of KHSO4 and HCl.
Microwave‐assisted regioselective one‐pot synthesis of trisubstituted pyridine scaffolds using K5CoW12O40.3H2O under solvent free conditions
Authors: Kantevari Srinivas , Chary Mahankhali Venu , Vuppalapati Srinivasu V. N. , Lingaiah N.
Published: March 2009

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A highly efficient, microwave‐assisted, regioselective synthesis of 2,3‐disubstituted‐6‐arylpyridines and new series of 7,7‐dimethyl‐2‐aryl‐5,6,7,8‐tetrahydroquinoline‐5‐ones from enaminones in the presence of K5CoW12O40.3H2O (1.0 mol %) as heterogeneous catalyst under solvent free conditions is reported.
Unsymmetrical indirect covariance processing of hyphenated and long‐range heteronuclear 2D NMR spectra ‐ Enhanced visualization of 2JCH and 4JCH correlation responses
Authors: Martin Gary E. , Hilton Bruce D. , Blinov Kirill A. , Williams Antony J.
Published: March 2009

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Recent reports have demonstrated the unsymmetrical indirect covariance combination of discretely acquired 2D NMR experiments into spectra that provide an alternative means of accessing the information content of these spectra. The method can be thought of as being analogous to the Fourier transform conversion of time domain data into the more readily interpreted frequency domain. Hyphenated 2D‐NMR spectra such as GHSQC‐TOCSY, when available, provide an investigator with the means of sorting proton‐proton homonuclear connectivity networks as a function of the 13C chemical shift of the carbon directly bound to the proton from which propagation begins. Long‐range heteronuclear chemical shift correlation experiments establish proton‐carbon correlations via heteronuclear coupling pathways, most commonly across three bonds (3JCH), but in more general terms across two (2JCH) to four bonds (4JCH). In many instances 3JCH correlations dominate GHMBC spectra. We demonstrate in this report the improved visualization of 2JCH and 4JCH correlations through the unsymmetrical indirect covariance processing of GHSQC‐TOCSY and GHMBC 2D spectra.
6‐Nitro‐1,2,3,4‐tetrahydroquinolines by a tandem reductive amination‐SNAr reaction
Authors: Bunce Richard A. , Nago Takahiro
Published: March 2009

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A tandem reductive amination‐SNAr reaction has been developed for the synthesis of 6‐nitro‐1,2,3,4‐tetrahydroquinolines. Treatment of 4‐(2‐fluoro‐5‐nitrophenyl)‐2‐butanone or 3‐(2‐fluoro‐5‐nitrophenyl)‐propanal with primary amines and sodium cyanoborohydride in methanol at room temperature provided good to excellent yields of the substituted tetrahydroquinolines. The reaction proceeded best with the ketone substrate using primary amines that were unbranched at the α‐carbon. The aldehyde also produced the target heterocycles, but these were accompanied by 10‐15% of the uncyclized side chain reductive amination products.
First synthesis of selenadiazolo[3,4‐i] Benzazepine derivatives
Authors: Abou Elmaaty Tarek M.
Published: March 2009

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5‐Methyl‐4‐nitro‐2,1,3‐benzoselenadiazole (1) was converted into (E)‐5‐(2‐dimethylamino)vinylbenzo‐[c](1,2,5)selenadiazole‐4‐amine (4) by initial treatment with dimethylformamide dimethyl acetal (DMFDMA) (2) followed by selective reduction using ammonium bromide in methanol. Compound 4 afforded the selenadiazolo[3,4‐i][1]benzazepine derivatives (7, 10, 13, 15) upon treatment with malononitrile (5), ethyl cyanoacetate (8) and cyanoacetamide (11) respectively.
Chemoselective reaction of formalin with 2‐(5‐substituted‐2‐hydroxybenzylamino)phenols: Synthesis of 6‐substituted 3‐(2‐hydroxyphenyl)‐3,4‐dihydro‐2H‐benzo[e][1,3]oxazines
Authors: Manikannan Ramaiyan , Muthusubramanian Shanmugam
Published: March 2009

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Reaction of 2‐(5‐substituted‐2‐hydroxybenzylamino)phenols (2) with formalin in ethanol under reflux has chemoselectively led to 2‐(6‐substituted‐2H—benzo[e][1,3]oxazin‐3(4H)‐yl)phenols (3) in good yield involving the ring closure of the hydroxyl group of the C‐aryl ring and not that of the N‐aryl ring.
Selective modification of bifunctional heterocyclic compounds containing amino and thioamide groups in acetic acid medium
Authors: Kolmakov Kirill A.
Published: March 2009

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In acetic acid medium, 2‐chloro‐4,6‐dimorpholin‐4‐yl‐[1,3,5]triazine undergoes amination by bifunctional heterocyclic compounds containing both amino and thioamide groups. The reactions are high‐yielding and selective; the thioamide functions are unaffected under the requisite conditions. The reactions do not proceed in satisfactory yields in other solvents and, thus, require acetic acid. The resulting thioamides, consisting of multiple biologically relevant residues, are easily alkylated at the sulfur (thiolthione) centers to furnish new thioethers in subsequent steps.
Synthesis of pyrazolo[3,4‐b]pyridines using ammonium acetate as green reagent in multi‐component reactions
Authors: Jachak Madhukar N. , Avhale Appasaheb B. , Ghotekar Bhausaheb K. , Kendre Dhananjay B. , Raghunath B. Toche
Published: March 2009

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Several new pyrazolo[3,4‐b]pyridine derivatives were synthesized by one pot cyclocondensation of the components; 5‐amino‐3‐aryl‐1H‐phenylpyrazoles, p‐substituted benzoylacetonitriles and some aldehydes. The condensations were most effective by using ammonium acetate as the base catalyst; triethylamine was also studied as a catalyst.
Synthesis and characterization of N‐arylsulfonylazetidines
Authors: Tan Songde , Chen Yiwen , Zingaro Ralph A. , Reibenspies Joseph H.
Published: March 2009

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A convenient method for the synthesis of N‐arylsulfonyl azetidines using N‐(3‐bromopropyl)‐arylsulfonamide with cesium carbonate and potassium iodide in DMF is reported. The reaction conditions are optimized and seven N‐arylsulfonyl azetidines have been synthesized in good yield using this method. The structures of compounds 2a and 2e were determined by X‐ray crystallography.
Synthesis of new imidazole derivatives
Authors: Nowak Krystyna , Szpakiewicz Barbara
Published: March 2009

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The derivatives of 1‐propyl‐ and 1‐butyl‐ of 2‐methyl‐5‐nitroimidazole containing phenylpiperazine, m‐chloro‐ and o‐methoxyphenylpiperazine attached at the end of alkyl chain were synthesed. For the obtained new compounds, the biological activity was predicted using the computer program PASS.
Convenient preparations of 2‐alkyl‐5‐oxopyrrolidine‐3‐carboxylic acids
Authors: Photiadou Anna D. , Stathakis Christos I. , Gallos John K.
Published: March 2009

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Reduction of the Michael addition products of anions of nitro compounds to dimethyl maleate led to the spontaneous formation of the respective 2‐alkyl‐5‐oxopyrrolidine‐3‐carboxylic acid methyl esters. Conventional hydrolysis of the later gave the desired compounds.
Regioselective photocyclization of (e)‐2‐(2,3,6‐trichlorostyryl)‐benzothiazole and synthesis of 3,4‐dichloro‐ and 4‐chlorobenzothiazolo[3,2‐α]quinolinium chlorides: A synthetic and theoretical study
Authors: Cox Osvaldo , Garcia Carmelo , Cordero Marisol
Published: March 2009

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A high degree of regioselectivity is observed in the photochemically induced cyclization of (E)‐2‐(2,3,6‐trichlorostyryl)benzothiazole (1a). According to the proposed mechanism, this compound was expected to afford two products, 3,4‐dichloro‐ and 1,4‐dichlorobenzothiazolo[3,2‐α]quinolinium chlorides (4aand4a', respectively). However, this reaction produced 3,4‐dichlorobenzazolo[3,2‐α]quinolinium chloride (4a) as the sole product. On the other hand, irradiation of (E)‐2‐(2,3,5‐trichlorostyryl)benzothiazole (1b) failed to produce the expected 1,3‐dichlorobenzothiazolo[3,2‐α]quinolinium chloride (4b). Furthermore, (E)‐2,3‐difluorostrylbenzothiazole (1c) also failed to give the corresponding 1‐fluorobenzothiazolo[3,2‐α]quinolinium fluoride (4c). Interestingly, the irradiation of 2,6‐dichlorostyrylbenzothialole (1d) produced 4‐chlorobenzothiazolo[3,2‐α]quinolinium chloride (4d) in excellent yield. This paper presents the results of these investigations and a mechanistic rationale for the outcome of this reaction based on steric arguments and theoretical studies using a combination of molecular mechanics (MM+) and semiempirical quantum mechanical calculations (PM3/RHF/CI). Two‐dimensional high field nmr methods were employed to make complete assignments of the proton and carbon spectra of all new compounds.
Synthesis, asymmetric aldol reactions, and x‐ray crystallography of some oxadiazinanone derivatives
Authors: Hitchcock Shawn R. , Davis Ryan A. , Richmond Daniel M. , Dore Delvis D. , Kuschel Stephanie L. , Vaughn Jeremy F. , Wolfe Jesse A. , Hamaker Christopher G. , Casper David M. , Dingle Jarvis
Published: March 2009

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A series of N4‐substituted oxadiazinanones have been synthesized from (1R,2S)‐norephedrine by a process of either reductive alkylation or arylation, N‐nitrosation, reduction and cyclization. These derivatives (R = ‐CH2Ph, ‐CH2C(CH3)3, ‐cyclo‐C6H11, ‐C6H5) have been acylated with propanoyl chloride and employed in the asymmetric Aldol reaction. The observed diastereoselectivities for the formation of the “non‐Evans” syn‐adduct ranged from 88:12 to 99:1. The hydrolysis of the Aldol adducts varied with the nature of the nitrogen substituent.
Pot, atom and step economic synthesis of fused three heterocyclic ring compounds under microwave irradiation in water
Authors: Shi Feng , Zhou Dianxiang , Tu Shujiang , Li Chunmei , Cao Longji , Shao Qingqing
Published: March 2009

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A new series of fused three heterocyclic ring compounds, consisting of a pyrazolo (ring A), a pyridine (ring B), and a pyrimidine (ring C) core, pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine derivatives were successfully synthesized by pot, atom and step economic (PASE) method under microwave irradiation in the presence of p‐toluene sulphonic acid in water.
Multicomponent reactions in chiral ionic liquids: A stereocontrolled route to mercaptopyranothiazoles
Authors: Yadav Lal Dhar S. , Yadav Beerendra S. , Rai Vijai K.
Published: March 2009

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A low hazardous, one‐pot, expeditious annulation involving tandem Knoevenagel, Michael and ring transformation reactions of 3‐arylrhodanines, aromatic aldehydes and a mercaptoacetyl transfer agent, 2‐methyl‐2‐phenyl‐1,3‐oxathiolan‐5‐one, diastereoselectively yields 6‐mercaptopyranothiazoles. The annulation is performed using a chiral ionic liquid (Pro2SO4) as the reaction medium and catalyst, and proceeds via an isolable intermediate.
Anion recognition properties of the neutral receptors bearing amide macrocycle
Authors: Shang X.‐F. , Cai Z.‐S. , Lin H.‐K. , Lin H.
Published: March 2009

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Neutral classes of amide‐based macrocycle have been synthesized and the anion binding abilities are assessed by UV‐vis titration and 1H nmr experiments. Results indicate that higher anion binding abilities are observed for H2PO4−, F− and AcO−, but almost no affinity for Cl−, Br−, I− and OH−. The 1H nmr spectra shows that the interactions between the receptors and fluoride anion depend on two factors, respectively: one is depend on hydrogen bonding, the other on deprotonation.
Synthesis and bio‐activity of novel iminophosphoranes
Authors: Mohan Ch. , Babu B. Hari , Raju C. Naga , Reddy C. Suresh , Reddy V. Janardhan
Published: March 2009

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The title compounds (5a‐j) were synthesized by a two step process. 4‐Chlorophenyl and bis(2‐chloroethyl) amino‐dibromophosphites (1a and 1b) were reacted with 1,8‐diaminonaphthalene (2) to form the diazaphosphinines (3a and 3b). They were further reacted with different alkyl azides (4a‐e) in THF at 50‐55 °C under N2 atmosphere to afford the corresponding iminophosphoranes (5a‐j). Their structures were established by elemental analysis, IR, 1H, 13C, 31P NMR and Mass spectral data. All of them exhibited moderate antibacterial activity.
Oxidation of bisnaphthols to spironaphthalenones, revisited
Authors: Khoramabadi‐Zad Ahmad , Yavari Isaa , Shiri Azam , Bani Azad
Published: March 2009

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Bis(2‐hydroxy‐1‐naphthyl)methane derivatives have been efficiently converted to their corresponding spirans through three methods, i.e. oxidation by TCCA under mild reaction conditions, Ph3Bi catalyzed air oxidation, and by electrochemical reaction. The first two methods are diastereoselective and give either of the two possible diastereomers, while the electrochemical method produces equal amounts of these diastereomers.
Syntheses of potassium 1,1‐dioxopyrido[4,3‐e]‐1,4,2‐dithiazine‐3‐thiolate and its application to the synthesis of novel sulfonamides with potential biological activity
Authors: Brzozowski Zdzislaw , Sâczewski Franciszek , Slawiński Jaroslaw
Published: March 2009

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Potassium 1,1‐dioxopyrido[4,3‐e]‐1,4,2‐dithiazine‐3‐thiolate 2 has been synthesized and applied to the syntheses of 7H‐1,1‐dioxopyrido[4,3‐e]‐1,4,2‐dithiazolium‐3‐thiolate 3 and 3‐methylthiopyrido[4,3‐e]‐1,4,2‐dithiazine 1,1‐dioxide 4 which provided easy access to a variety of its 3‐amino derivatives 5‐10. Hydrazinolysis of 7, 8 and 10 afforded the corresponding 3‐amino‐2‐(1,4‐dihydro‐4‐thioxopyrid‐3‐ylsulfonyl)guanidines 11‐13. Subsequent reaction of 12 with 4‐chlorobenzaldehyde gave condensation product 14. 1,4‐Dihydro‐2‐thioxopyridine‐3‐sulfonamide 15 was also prepared from the potassium salt 2 upon alkaline hydrolysis, whereas alkylation of 15 gave the appropriate S‐substituted derivatives 16‐19 or S,N‐disubstituted compounds 20‐21.
Phenacyl esters of acetic acid derivatives and their application for the synthesis of 2‐oxo‐4‐phenyl‐5‐(phenylhydrazono)‐2,5‐dihydro‐furan‐3‐derivatives
Authors: Hlaváč Jan , Hradil Pavel , Mělnický Radek , Kvapil Lubomír , Šlézar Petr , Grepl—— Martin , Hradil Pavel , Lyčka Antonín , Grepl Martin
Published: March 2009

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Coupling of various substituted phenacyl acetates 1 and diazonium salts 3 was studied. If the phenacyl acetates were substituted by an electronaceptor group such as CN or COOEt 3‐substituted phenyl‐5‐(phenyl‐hydrazono)‐5H‐furan‐2‐ones 4 were formed. Also synthesis of aza and diaza analogs is described. The compounds were characterized using MS and NMR spectroscopy.
Synthesis of novel symmetrical bis‐schiff bases of 5,5′‐methylenebis(2‐aminothiazole)
Authors: Shockravi Abbas , Sadeghpour Mahdieh , Olyaei Abolfazl
Published: March 2009

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Novel symmetrical bis‐Schiff bases have been prepared cleanly and efficiently in the presence of formic acid catalyst in methanol from the reaction of symmetrical primary bis‐amine of 5,5′‐methylenebis(2‐aminothiazole) (1) and a series of aromatic aldehyde derivatives under mild conditions. The advantages of this reaction are simplicity of the reaction procedure, simple work‐up and pure products with high yields. The structures of all the new synthesized symmetrical bis‐Schiff bases were confirmed by elemental analyses, IR, 1H‐NMR, 13C‐NMR and mass spectra.
Synthesis and biological activity of 3‐[(6‐chloropyridin‐3‐yl)methyl]‐6‐substituted‐6,7‐dihydro‐3H‐1,2,3‐triazolo[4,5‐d]‐pyrimidin‐7‐imines
Authors: Chen Xiao‐Bao , Shi De‐Qing
Published: March 2009

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A series of 3‐[(6‐chloropyridin‐3‐yl)methyl]‐6‐substituted‐6,7‐dihydro‐3H‐1,2,3‐triazolo[4,5‐d]pyrimidin‐7‐imines were designed and synthesized via a multi‐step sequence using 2‐chloro‐5‐(chloromethyl)‐pyridine as the starting material. Various primary aliphatic amines, hydrazine and hydrazide reacted with 3 to obtain the cyclization products 4. Their structures were confirmed by 1H NMR and elemental analyses, some of them were also confirmed by IR, 13C NMR, MS and single crystal X‐ray diffraction. The preliminary bioassay indicated that some of the target compounds 4 displayed moderate to weak fungicidal activity and insecticidal activity.
Synthesis and reactions of n‐methyl‐4‐(methylthio)thieno[2,3‐d]‐pyrimidinium salts
Authors: Maruoka Hiroshi , Okabe Fumi , Yamagata Kenji
Published: March 2009

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Two methods for the preparation of N‐methyl‐4‐(methylthio)thieno[2,3‐d]pyrimidinium salts 6a,b and 13a,b are described. Treatment of 6a,b and/or 13a,b with active methylene compounds such as malononitrile and ethyl cyanoacetate in the presence of sodium methoxide caused nucleophilic addition followed by elimination of methanethiol, giving the corresponding N‐methyl‐4‐ylidenethieno[2,3‐d]‐pyrimidines 7a,b, 8a,b, 14a,b and 15a,b.
The reaction of cyclohexanone azine with cyanoacetic acid‐acetic anhydride
Authors: Nakhai Azadeh , Bergman Jan , Raftery Jim , Joule John A.
Published: March 2009

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The reaction of cyclohexanone azine with a reagent produced by brief heating of cyanoacetic acid with acetic anhydride produced a highly substituted dihydropyrazolone.
Chemistry and application of 4‐oxo‐4H‐1‐benzopyran‐3‐carboxaldehyde
Authors: Ghosh Chandra Kanta , Patra Amarendra
Published: March 2009

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The Chemistry and application of the title aldehyde and some simple derivatives thereof are reviewed.
Diverse reactivity of α‐carbanions derived from alkylidenephosphoranes toward 2‐(1λ5‐diazynylidene)‐1H‐indene‐1,3‐(2H)dione. General approach to conjugated oxadiazines, pyridazines and spiro[3]pyrazoles
Authors: Abdou Wafaa M. , Khidre Maha D. , Khidre Rizk E.
Published: March 2009

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Different types of phosphonium carbanions were applied to 2‐diazonio‐1,3‐dioxo‐2,3‐dihydro‐1H‐inden‐2‐ide (1) in order to synthesize a number of condensed and fused N‐heterocycles. When 1 was treated with cyanomethyltriphenylphosphonium chloride oxadiazine‐, and pyridazine derivatives were obtained whereas bis‐indanylidene derivatives resulted from the reaction of 1 with methyl_ and ethyltriphenylphosphonium bromides. On the other hand, a series of substituted and unsubstituted spiro[3′]pyrazoles were obtained from the di azo substrate when reacted with vinyl_and allyltriphenylphosphonium bromides.
1‐Arylsulfonyl‐2‐styrylsulfonylthenes — source for a new class of bis heterocycles
Authors: Padmavathi Venkatapuram , Radhalakshmi Thunga , Reddy Gali Sudhakar , Padmaja Adivireddy
Published: March 2009

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New and novel sulfone linked bis heterocycles_ bis pyrroles and pyrrolyl pyrazolines are prepared from 1‐arylsulfonyl‐2‐styrylsulfonylethenes by 1,3‐dipolar cycloaddition methodology.
Synthesis and characterization of some substituted chromones as an anti‐infective and antioxidant agents
Authors: Rode Milind , Gupta R. C. , Karale B. K. , Rindhe S. S.
Published: March 2009

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A series of substituted chromones were synthesized and characterized by spectral data. Some of the synthesized compounds were tested for in‐vitro antibacterial, antifungal and antioxidant activity. Two compounds have shown very good antioxidant activity and some of the chromone derivatives have exhibited moderate antibacterial and antifungal activity.
Synthesis of a novel class of 3‐(2′‐benzothiazolyl)‐2,3‐dihydroquinazolin‐4(1H)‐ones under solvent‐free and catalyst‐free conditions
Authors: Shaabani Ahmad , Rahmati Abbas , Moghimirad Jafar
Published: March 2009

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A solvent‐ and catalyst‐free one‐pot three‐component condensation reaction approach was developed for the synthesis of a new class of 3‐(2′‐benzothiazolyl)‐2,3‐dihydroquinazolin‐4(1H)‐ones in relatively good yields.
Synthesis and mutagenic potency of structural isomers of 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine
Authors: Chrisman W. , Tanga M. J. , Knize M. G.
Published: March 2009

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Synthesis of 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), three structural isomers, and two desphenyl PhIP congeners has been carried out. Mutagenic potency was evaluated using S. typhimurium strain TA98 in the Ames test. Mutagenic potency increased in relation to structural features in these heterocyclic amines that allow extended resonance between the phenyl and imidazo[4,5‐b]pyridine N2‐amino substituents. By contrast, PhIP isomers, whose substitution disallows involvement of the phenyl group in their aminoimidazo resonance hybrids, and desphenyl congeners were from 86‐ to 234‐fold less mutagenic than PhIP.
Synthesis of new fused isoquinolines via reissert compounds
Authors: Fuchs Christian , Bender Christoph , Ziemer Burkhard , Liebscher Jürgen
Published: March 2009

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Reissert compounds 2 derived from isoquinoline, chloroformates and TMS‐cyanide were alkylated in position 1. The resulting alkylation products 3 as well as the precursors 2 reacted with Grignard reagents affording imidazoisoquinolines 4, 5, 7 and 8 by addition to the cyano group and Grignard reduction or by twofold addition to the cyano group, respectively. In both cases the alcohol of the 2‐alkoxycarbonyl moiety was eliminated by attack of the N‐atom at the carbonyl carbon atom. Under acid conditions, 1‐benzylated Reissert compound 3h cyclised by attack of the resulting N‐acyliminium C‐atom at the o‐position of the benzyl ring to form tetracyclic 1,3‐bridged tetrahydroisoquinolines 10 and 11. Bromocyclisation of 1‐allyl‐2‐menthyloxycarbonyl‐substituted Reissert compounds 3b, c led to tricyclic dibromo products 12, in which the menthol moiety was split off and addition to the enamine double bond occurred. A 2‐menthyloxycarbonyl group in Reissert compounds 2a and 3 failed to exert an asymmetric induction in all cases.
Preparation of new 2‐amino‐ and 2,3‐diamino‐pyridine trifluoroacetyl enamine derivatives and their application to the synthesis of trifluoromethyl‐containing 3H‐pyrido[2,3‐b][1,4] diazepinols
Authors: Bonacorso Helio G. , Lourega Rogério V. , Righi Fernando J. , Deon Everton D. , Zanatta Nilo , Martins Marcos A. P.
Published: March 2009

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The synthesis of a novel series of the intermediates N2(N3)‐[1‐alkyl(aryl/heteroaryl)‐3‐oxo‐4,4,4‐trifluoroalk‐1‐en‐1‐yl]‐2‐aminopyridines [F3CC(O)CHCR1(2NHC5H3N)] and 2,3‐diaminopyridines [F3CC(O)CHCR1(2‐NH2‐3‐NHC5H3N)], where R1 = H, Me, C6H5, 4‐FC6H4, 4‐CIC6H4, 4‐BrC6H4, 4‐CH3C6H4, 4‐OCH3C6H4, 4,4′‐biphenyl, 1‐naphthyl, 2‐thienyl, 2‐furyl, is reported. The corresponding series of 2‐aryl(heteroaryl)‐4‐trifluoromethyl‐3H‐pyrido[2,3‐b][1,4]diazepin‐4‐ols obtained from intramolecular cyclization reaction of the respective trifluoroacetyl enamines or from the direct cyclocondensation reaction of 4‐methoxy‐1,1,1‐trifluoroalk‐3‐en‐2‐ones with 2,3‐diaminopyridine, under mild conditions, is also reported.
Enantioselective 1,3‐dipolar cycloaddition reactions using chiral lanthanide catalysts
Authors: Gołȩbiewski W. Marek , Gucma Mirosław
Published: March 2009

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Regio‐ and stereoselective 1,3‐dipolar cycloaddition of nitrile oxides to internal 2‐pentenols, α,β‐unsaturated esters and amides catalyzed by R‐(+) BINOL‐lanthanide complexes affords corresponding 3‐aryl‐2‐isoxazolines with enantioselectivities up to 89% ee.
An efficient synthesis of pyrazolo[3,4‐b]pyrrolo[2,3‐d]pyridines from 5‐aminopyrazoles and cyclic β‐keto ester
Authors: Toche Raghunath B. , Ghotekar Bhausaheb K. , Kendre Dhananjay B. , Kazi Muddassar A. , Jachak Madhukar N.
Published: March 2009

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5‐Chloroethylpyrazolo[3,4‐b]pyridines were synthesized by condensation of 5‐aminopyrazoles with α‐acetyl γ‐butyrolactone followed by cyclization treating with phosphorous oxychloride. 5‐Chloroethyl‐pyrazolo[3,4‐b]pyridines, thus obtained, were then converted to the corresponded tricyclic pyrazolo[3,4‐b]‐pyrrolo[2,3‐d]pyridines by treating with some primary amines.
Synthesis, structures of some unsymmetrical 3,6‐disubstituted‐1,2,4,5‐tetrazines
Authors: Hu Wei‐Xiao , Xu Feng
Published: March 2009

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A series of new unsymmetrical 3‐phenyl‐6‐benzyl‐1,2,4,5‐tetrazine derivatives 10a‐i were synthesized and characterized by IR, NMR, MS, and element analysis. The structures of 4a, 10c, 10d and 10h were analyzed by X‐ray crystallography, which had intermolecular C‐H‐N, C‐H‐Cl, C‐H‐II and II‐II interactions.
Synthesis and characterization of soluble tetra(2‐methoxyethoxy)metallophthalocyanines
Authors: Gao Junshan , Cong Fangdi , Du Xiguang , Duan Wenjuan , Li Jianxin
Published: March 2009

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Four soluble tetra(2‐methoxyethoxy)metallophthalocyanines 4a‐4d were, in two steps, synthesized from phthalonitrile 1 and 2‐methoxyethanol 2, and characterized by MS, 1H NMR, UV‐vis, IR and elemental analysis, as well as Cyclic voltammetry.
An efficient synthesis of 5‐benzoyloxazolines by regio‐ and stereo‐controlled reaction of N‐substituted 2‐benzoylaziridines under microwave irradiation
Authors: Samimi Heshmat A. , Mamaghani Manouchehr , Tabatabaeian Khalil
Published: March 2009

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Several N‐acyl‐2‐benzoylaziridines were prepared conveniently in good to high yields (71‐93%) and used in the preparation of 5‐benzoyloxazolines (76‐91%) by a regio‐ and stereo‐controlled reaction in the presence of Nal as an efficient catalyst under microwave irradiation in short reaction times (5‐10 mins). The structure of the regioisomeric product was confirmed by X‐ray analysis.
Synthesis of some indole based spiro and condensed heterocycles as potential biologically active agents
Authors: Sharma R. L. , Kour Daljeet , Singh Jasbir , Kumar Surinder , Gupta Poonam , Gupta Shallu , Kour Bhavneet , Sachar Anand
Published: March 2009

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The reactions of isatin with cyclic ketones, viz camphor (dl, Mp 174–181°C, specific rotation −1.5° to +1.5°) available from s. d. fine‐ CHEM LTD and menthone (I, Bp 207°–210° C, density 0.893 g/mL) isolated from peppermint oil, in refluxing ethanol in the presence of t‐BuOK afforded the corresponding indolylidene compounds (3a) and (3b) (a mixture of stereochemical isomers E and Z in both the cases) respectively, all obtained as racemates. Cyclocondensation of (3a) and (3b) with thiourea, urea, ethylenediamine and o‐phenylenediamine afforded new spiro (4a,b‐7a,b) and condensed systems (4a',b'‐7a',b') respectively, whereas with 2‐aminopyridine spiro compounds exclusively were obtained (8a,8b). All the new spiro and condensed systems generated have been isolated as racemates and evaluated for their antimicrobial activity.
β‐Oxoanilides in heterocyclic synthesis: An expeditious synthesis of new polyfunctionally substituted pyridine and pyrazole derivatives
Authors: Hussein A. M. , Harb A. A. , Mousa I. A.
Published: March 2009

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3‐Oxo‐N‐{4‐[(pyrimidin‐2‐ylamino)sulfonyl]phenyl}butanamide 3 was condensed with (DMF‐DMA) in refluxing dry dioxane to yield branched structure 4 not its linear isomeric 5. Compound 4 readily reacted with active methylene to yield compounds 8a‐c, 14, 17 and 20 respectively. Also enaminone 4 reacted with phenyl hydrazine giving 24 and 25. In contrast, when compound 4 reacted with hydrazine hydrate in the same experimental conditions pyrazole derivative 27 was obtained. Furthermore, condensation of anilide 3 with triethylorthoformate in refluxing acetic anhydride afforded the ethoxy methylene derivative 28. On the other hand, compound 28 was reacted with active methylene reagents, and hydrazines to afford the products identical in all respects (mp., mixed mp., and spectral data) with those corresponding to compounds 6‐27 respectively. Similarly, compound 3 was reacted with hydrazine hydrate to afford the reaction product 29. Also, compound 3 reacted with cyanoacetamide in refluxing ethanolic pipridine solution to yield the pyridine derivative 30. Finally, 3 reacted with hydroxylamine hydrochloride in refluxing ethanol/sodium acetate solution to yield the acyclic oxime derivative 31.
A new convenient synthesis of 2,4‐disubstituted‐1,2,4‐triazolo[1,5‐a] quinazolin‐5(4H)‐ones
Authors: Shawali Ahmad S. , Hassaneen Hamdi M. , Shurrab Nabil Kh.
Published: March 2009

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A novel series of 2,4‐disubstituted‐1,2,4‐triazolo[1,5‐a]quinazolin‐5(4H)‐ones were prepared by Dimroth rearrangement of their respective isomers namely 1,4‐disubstituted‐[1,2,4]triazolo[4,3‐a]‐quinazolin‐5(4H)‐ones. The latter were prepared via new synthetic strategy based on 1,5‐elecrocyclization of the respective N‐(4‐oxo‐3‐phenylquinazolin‐2‐yl)nitrilimines.
Syntheses and fluorescence of salicylaldimine schiff base derivatives of 1,1′‐di(aminoethylaminocarbonylalkyl)‐2,2′‐biimidazole
Authors: Barnett William M. , Carr Peris J. , Counsil Joseph A. , Collier Harvest L.
Published: March 2009

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The amide‐amine, 1,1′‐di(aminoethylaminocarbonylethyl)‐2,2′‐biimidazole (DAEPB) (1), and subsequent Schiff base imine product, 1,1′‐di(salicylaldiminoethylaminocarbonylethyl)‐2,2′‐biimidazole (DSEB) (2a), have been synthesized from the ester, 1,1′‐di(ethoxycarbonylethyl)‐2,2′‐biimidazole (DEPB). Additionally, 1,1′‐di(salicylaldiminoethylaminocarbonylmethyl)‐2,2′‐biimidazole (DSMB) (2b), was prepared from its corresponding amide‐amine. All compounds were characterized with FTIR, NMR and elemental analyses. The salicylaldimines, compounds (2a) and (2b), exhibit fluorescence at 540 and 520 nm, respectively, over a broad range of excitation wavelengths.
Efficient synthesis of 6‐aryl‐2‐chloronicotinic acids via pd catalyzed regioselective suzuki coupling of 2,6‐dichloronicotinic acid
Authors: Ma Mingliang , Li Chengwei , Li Xiaoyan , Wen Ke , Liu Yahu A.
Published: March 2009

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A regioselective Suzuki coupling of 2,6‐dichloronicotinic acid with aryl boronic acids to synthesize 6‐aryl‐2‐chloronicotinic acids is described. Regioselectivity was achieved in aqueous dioxane using the routinely used catalyst Pd(PPh3)4.
Synthesis and reactions of some new benzopyranone derivatives with potential biological activities
Authors: El‐Desoky El‐Sayed I. , Al‐Shihry Shar S.
Published: March 2009

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Reaction of visnaginone which derived from the naturally occurring compound “visnagine”, with allyl bromide gave O‐allyl visnaginone 1, which underwent Claisen rearrangement to yield 7‐allylbenzofuran 2 derivative. Vilsmeier Haack formylation of 2 afforded our versatile starting compound furochromene‐6‐carboxaldehyde (3) which was condensed with cyclohexane‐1,3‐dione, indandione, malononitrile or ethyl cyanoacetate to yield the ylidene nicotinonitrile and pyridone derivatives 4,7,10a‐b. Reaction of 3 with aniline or aniline acting on multiple function X‐H (X = NH, O, S) at its ortho position afforded the corresponding anils, imidazolylfurochromene and azepines compounds 11‐17. On the other hand, oxidation of visnagin afforded chromene‐6‐carboxaldehyde derivative 18 which was condensed with different aryl or (heteroaryl) acetonitrile followed by hydrolysis to give pyrano[3,2‐g]chromen‐4,8‐dione derivatives 20a‐d and 22.
N‐donor ligand as catalyst: A simple aza‐michael addition reaction in aqueous media
Authors: Pawar Shivaji S. , Dekhane Deepak V. , Thore Shivaji N. , Shingare Murlidhar S.
Published: March 2009

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A novel approach for the Aza‐Michael addition reactions between various amines and α,β‐unsaturated esters, nitriles and ketones using N‐donor Ligand catalyst (3 mol %) is described. The reactions are carried out in aqueous media at an ambient temperature to afford the products in excellent yields.
Synthesis, structure and investigations of tuberculosis inhibition activities of new 4‐methyl‐1‐substituted‐1H‐1,2,4‐triazole‐5(4H)‐thione
Authors: Wujec Monika , Siwek Agata , Swatko‐Ossor Marta , Mazur Liliana , Rzaczynska Zofia
Published: March 2009

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By the reaction aminomethylation, chloromethylation and acylation of 4‐methyl‐4H‐1,2,4‐triazole‐3‐thiol, 4‐methyl‐1‐substituted‐1H‐1,2,4‐triazole‐5(4H)‐thione 1‐8 were obtained. Molecular structure of the obtained compounds was confirmed by an elemental analysis, IR, 1H NMR and 13C NMR spectra and additionally by X‐ray analysis for 2. Six new compounds 1,2,4‐7 were tested for antibacterial activity against Mycobacterium smegmatis, Mycobacterium phlei and avirulent strain Mycobacterium H37Ra.
Morphological changes during postembryonic development in two species of neotropical harvestmen (Opiliones, Laniatores, Cranaidae)
Authors: Townsend Victor R. , Rana Nouman J. , Proud Daniel N. , Moore Michael K. , Rock Philip , Felgenhauer Bruce E.
Published: March 2009

Morphological changes during postembryonic development in the Cranaidae are described on the basis of the examination of an incomplete series of larvae, nymphs, and adults ofPhareicranaus calcariferusandSantinezia serratotibialis. The life histories of these species are hypothesized to consist of six nymphal stages, featuring the appearance of secondary male sexual characteristics in the antepenultimate nymph (N5). Color and body shape change dramatically during development. Growth rates for nymphs based upon leg measurements were similar for both species. InS. serratotibialis, the greatest increase in leg size occurred from larva to 1st nymph. The tarsomeres of legs I–IV varied by 1–2 segments per leg for each nymph stage, with the number of tarsal segments increased by 1–2 segments at each stage. Adults had nearly twice as many tarsomeres on leg II than other legs. Ontogenetic changes were observed in the armature of the proximal cheliceral segment, ocularium, pedipalp, opisthosoma, distitarsus III and IV, and leg IV. Morphological changes in postembryonic development in cranaid harvestmen are similar to those reported for other Laniatores. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.
A mass spectrometric study on meloxicam metabolism in horses and the fungusCunninghamella elegans,and the relevance of this microbial system as a model of drug metabolism in the horse
Authors: Tevell Åberg Annica , Olsson Charlotte , Bondesson Ulf , Hedeland Mikael
Published: March 2009

This paper describes a study where the metabolism of the non‐steroidal anti‐inflammatory drug meloxicam was investigated in six horses and in the filamentous fungusCunninghamella elegans. The metabolites identified were compared between the species, and then the fungus was used to produce larger amounts of the metabolites for future use as reference material.C. elegansproved to be a good model of phase I meloxicam metabolism in horses since all four metabolites found were the same in both species. Apart from the two main metabolites, 5′‐hydroxymethylmeloxicam and 5′‐carboxymeloxicam, a second isomer of hydroxymeloxicam and dihydroxylated meloxicam were detected for the first time in horse urine and the microbial incubations. Phase II metabolites were not discovered in theC. eleganssamples but hydroxymeloxicam glucuronide was detected intact in horse urine for the first time in this study. Urine from six horses was further analyzed in a semi‐quantitative sense and 5′‐hydroxymethylmeloxicam gave peaks with much higher intensity compared to the parent drug and the other metabolites, and was detected for at least 14 days after the last given dose in some of the horses. From the results presented in this article, we suggest that analytical methods developed for the detection of meloxicam in horse urine after prohibited use should focus on the 5′‐hydroxymethyl metabolite and thatC. eleganscan be used to produce large amounts of this metabolite for potential future use as a reference compound. Copyright © 2009 John Wiley & Sons, Ltd.
Ion‐ Beam Modification of Peo Based Polymer Electrolytes
Authors: Singh Divya , Saxena Amit , Pandey Shri Prakash , Tomar Sandeep Kumar , Asokan K. , Kanjilal D. , Kumar Ranvir , Bhattacharya Bhaskar
Published: March 2009

In this paper, we report the ion beam interaction with a well explored ion conducting polymer electrolyte, viz., polyethylene oxide complexed with sodium iodide (PEO:NaI). Li3+ ions at 50 MeV were bombarded on the film at different flux. The conductivity modulation of the films has been reported due to interaction at different fluence. The increase in the total conductivity is explained in terms of the change in the number of charge carriers and the dielectric constant of the polymer electrolyte films.