bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of a stereoselective and chemoselective approach to trans‐2,3‐disubstituted‐4‐chromanones
Authors: Chambers R. J. , Marfat A. 
Published: March 2009

AbstractA direct synthesis of chromanones 10 and 11 was achieved in five steps from acetophenone 1 in an overall yield of 37% and 53% respectively. The requisite 2,3‐trans stereochemistry in chromanone 10 and 11 was set by a chemoselective and stereoselective conjugate reduction of chromones 8 and 9.
Synthesis of 2,6‐di‐tert‐butylphenols linked to 1,3,4‐oxadiazoles and 1,3,4‐thiadiazoles
Authors: Kramer James B. , Boschelli Diane H. , Connor David T. 
Published: March 2009

AbstractThe preparation of a series of analogs of 2,6‐di‐tert‐butylphenol linked to a 1,3,4‐oxadiazole or 1,3,4‐thiadiazole via an ethylene or methyleneoxy spacer is discussed.
Synthesis and preliminary cytotoxic activity of dimethoxy‐acridines and dimethoxynitroacridines
Authors: Monge A. , Martínez‐Crespo F. J. , Santamaría L. , Narro S. , De Ceráin A. López , Hamilton E. , Barker A. J. 
Published: March 2009

AbstractThe preparation of a series of dimethoxy and dimethoxynitroacridines and their activity in oxic and hypoxic cells is reported. Anthranilic acids 1,4,14 were prepared according to the Ullmann condensation. 9‐chloroacridines were obtained from anthranilic acids by refluxing in phosphorus oxychloride. The synthesis of two new acridine dimers 9,10 is described. Nitration of 9‐chloro‐2,4‐dimethoxyacridine 15 gave 3‐nitro isomer 19. By phenol‐mediated coupling reaction from all the 9‐chloroacridines, the respective 9‐(alkylamino)acridines were obtained. By nitration of 17 a new 2,4‐dimethoxy‐3,7‐dinitroacridine 21 was prepared
Synthesis of 6‐(pyrrol‐1‐yl)purine and of some of its 9‐glycosides
Authors: Haidoune M'Barek , Mornet René 
Published: March 2009

AbstractAdenine reacts slowly with 2,5‐dimethoxytetrahydrofuran (3) in a dilute acetic acid solution in methanol‐water, to give 6‐(pyrrol‐1‐yl)purine (4). Under more acidic conditions, 4 is partly transformed to 6‐(indol‐1‐yl)purine (5) and other unidentified products. The reaction may be used for the preparation of 9‐glycosides of 4 from the corresponding adenine derivatives provided their 9‐glycosyl linkage is somewhat resistant to acid hydrolysis.
Stereochemical effects in the nitrosation of some α,β‐unsaturated ketoximes. Formation of 1‐hydroxypyrazole 2‐oxides and 4‐oximino‐4,5‐dihydroisoxazoles
Authors: Hansen John F. , Easter John A. 
Published: March 2009

AbstractSeveral α,β‐unsaturated ketoximes R1CH=CHC(=NOH)R2 were nitrosated using butyl nitrite in aqueous ethanol in the presence of copper(II) sulfate and pyridine. The product distribution varied depending on whether the oxime hydroxyl group was syn or anti with respect to the carboncarbon double bond. The anti‐oximes gave the copper complexes of 1‐hydroxypyrazole 2‐oxides in high yields. The isomeric syn‐oximes gave lower yields of the pyrazole complexes along with 4‐oximino‐4,5‐dihydroisoxazole derivatives. For the syn‐oximes where R1 is phenyl and R2 is either methyl or ethyl, conversion of the oximes to the parent ketones was also observed. The results may be explained by processes involving N‐nitrosonitrone intermediates.
1,3‐Dipolar cycloaddition reactions of nitrones with vinylacetic olefins in the racemic series and synthesis of δ‐lactams via isoxazolidines
Authors: Chanet‐Ray Josette , Charmier‐Januario Marie Odile , Vessière Roger , Zuccarelli Marie 
Published: March 2009

AbstractA study of the cycloaddition behavior of a series of esters and nitriles α‐chloro‐ and α‐hydroxyvinyl‐acetic dipolarophiles with C‐aryl‐N‐alkylnitrones has been carried out. Regiospecific cycloadditions are observed; the reactions lead to a mixture of 5‐substituted isoxazolidines either erythro or threo, wherever the nitrone is involved. We report the synthesis of some δ‐lactams in which isoxazolidines are used as latent synthons.
The reactions of heterocyclic isothiocyanates bearing an ortho ester group with N‐nucleophiles. The scope and some limitations of the reaction
Authors: Urleb Uroš 
Published: March 2009

AbstractHeterocyclic isothiocyanates bearing an o‐ester group were converted into thiourea derivatives 2, 5, 6, 7, and 9 using sterically large primary amines or aminoacids, and to the fused ring systems, e.g. 12H‐pyrido[3′,2′:4,5]pyrimido[2,1‐b]benzothiazol‐12‐one (3), and 6,7‐dihydro‐9H‐thiazolo[3,2‐a]thieno[3,2‐d]‐pyrimidin‐9‐one (13), respectively, using bifunctional reagents such as 2‐aminothiophenol or cysteamine.
Unexpected behaviour of the oxidizing agent sodium m‐nitrobenzenesulfonate: Synthesis of a new class of 5‐hydroxy benzopyrano‐[4,3‐c]pyridazin‐3(2H)‐ones
Authors: Cignarella Giorgio , Barlocco Daniela 
Published: March 2009

AbstractSodium m‐nitrobenzene sulfonate, widely used in dehydrogenation of 4,5‐dihydro‐3(2H)‐pyridazinones to their corresponding aromatic derivatives, behaves in an unexpected way when 4,4a‐dihydro‐5H[1]benzopyrano[4,3‐c]pyridazin‐3(2H)‐ones are employed as substrate. The synthesis of a new class of 5‐hydroxy[1]benzopyrano[4,3‐c]pyridazin‐3(2H)‐ones is described.
An improved one‐step method to prepare some diaza‐crown ethers and the cation complexation properties of 4,10‐diaza‐18‐crown‐6 with two transition metal ions
Authors: Krakowiak Krzysztof E. , Maas Garren E. , Bradshaw Jerald S. , Hathaway Jon K. , Izatt Reed M. 
Published: March 2009

Abstract4,10‐Diaza‐15‐crown‐5, 4,10‐diaza‐18‐crown‐6, 4,13‐diaza‐21‐crown‐7, and 4,16‐diaza‐24‐crown‐8 were prepared by an improved method from the appropriate oligothylene glycol diiodides and diamines. The thermodynamic values of log K, ΔH and ΔS for the interaction of 4,10‐diaza‐18‐crown‐6 with Pb2+ and Ag+ were determined by a calorimetric titration method and compared with thermodynamic values for interactions of 4,13‐diaza‐18‐crown‐6 with the same cations. The thermodynamic values were found to be different for the two diaza‐crown ligands. 4,10‐Diaza‐18‐crown‐6 and its 4,13‐diaza‐crown analog formed precipitates when treated with Co2+, Cd2+, Cu2+, and Ni2+ so that no thermodynamic data are reported for these interactions.
Synthesis and 13C NMR study of some N‐substituted 4‐iodo‐ and 3,4‐diiodopyrazoles
Authors: Holzer Wolfgang , Pöcher Ingrid 
Published: March 2009

AbstractThe synthesis of some novel N‐1 substituted 4‐iodo‐ and 3,4‐diiodopyrazoles starting from the corresponding NH‐pyrazoles is described. On basis of their 13C nmr data and those of already known related congeners the influence of iodo‐ as well as N‐1 substituents on pyrazole 13C chemical shifts and 13C,1H spin coupling constants is investigated.
Stereoselective reduction of new fused azoninones with a bridgehead nitrogen
Authors: Berkes Dusan , Bar Nathalie , Decroix Bernard 
Published: March 2009

AbstractThe synthesis of methanothienoazoninones 5a,b is described starting from 2(3)‐halogenomethylthio‐phenes. Their reduction with sodium borohydride led to the corresponding aminoalcohols 6a,b with a complete stereoselectivity.
Heterocyclization of propenethioamides: A direct synthesis of 1,4‐thiazepine ring systems
Authors: Cocco Maria Teresa , Congiu Cenzo , Onnis Valentina 
Published: March 2009

AbstractThe heterocyclization of 3‐aminopropenethioamides 1 and 2 with 2‐bromoacetophenone is reported. The p‐toluenesulphonic acid catalyzed reaction gives a direct route to 1,4‐thiazepines 3 and 5, while in the presence of triethylamine thiophene 4 and 1,4‐thiazepin‐5‐one 6 are obtained.
Synthesis of 3‐nitrophthalonitrile and tetra‐α‐substituted phthalocyanines
Authors: George Robert D. , Snow Arthur W. 
Published: March 2009

AbstractAn efficient synthesis of phthalocyanines prepared from ortho‐substituted phthalonitriles is described. The precursor to these phthalocyanines, 3‐nitrophthalonitrile, is a key reagent for syntheses of phthalonitriles substituted at the 3‐position by means of nucleophilic aromatic substitutions. An example of this type of phthalocyanine, prepared from 3‐(4‐cumylphenoxy)phthalonitrile, is compared with the phthalocyanine derived from 4‐(4‐cumylphenoxy)phthalonitrile. Substitution of the phthalocyanine at this more sterically crowded site causes a 20 nm bathochromic shift of the Q‐band (π‐π* transition).
Synthesis of triflouromethylated pyridinecarbonitriles
Authors: Cocco Maria Teresa , Congiu Cenzo , Onnis Valentina 
Published: March 2009

AbstractEnaminonitriles 1 react in mild conditions with β‐trifluoroacetylvinyl ethers 2 to give the pyridine derivatives 4. The reaction involves the formation of the intermediate 3, that can be isolated when enol ether 2a is used.
Anodic cyanation of 1‐methylpyrazole
Authors: Yoshida Kunihisa , Toyo‐Oka Yoshimasa , Takeda Kazusada 
Published: March 2009

AbstractThe electrooxidation of 1‐methylpyrazole in methanol containing sodium cyanide produced 1‐methyl‐pyrazole‐4‐carbonitrile2and −5‐carbonitrile3in yields of 23 and 8%, respectively (2e‐oxidation products), together with 4‐methoxy‐1‐methylpyrazole‐5‐carbonitrile4(4e‐oxidation product, 4%).
2‐Aminopyridine derivatives as potential chiral auxiliaries
Authors: Parker Julie A. , Stanforth S. P. 
Published: March 2009

Abstract2‐Bromopyridine and 2‐bromo‐6‐methoxymethylpyridine reacted with an excess of 1‐phenylethylamine at reflux giving the aminopyridine derivatives 3a and 3b respectively.
2,4,6‐trichloropyrimidine. Reaction with ethanolamine and diethanolamine
Authors: Delia Thomas J. , Stark Derron , Glenn Steven K. 
Published: March 2009

Abstract2,4,6‐Trichloropyrimidine, 1, reacts with neutral nucleophiles, such as ethanolamine and diethanolamine, to produce both mono‐ and disubstituted derivatives resulting from replacement of either one (2 and 3) or two (4) chlorine atoms. The third chlorine could not be replaced by these nucleophiles. Failure of this final step was attributed to intramolecular hydrogen bonding of the nucleophiles.
The synthesis of 1,2,3,3a,4,5,6,11‐octahydro‐6,11a‐methano‐11aH‐benzo[4,5]cycloocta[1,2‐c]pyrroles. As new heterocyclic ring system
Authors: Ciganek Engelbert , Wright Ann S. , Nemeth Gregory A. 
Published: March 2009

AbstractThe synthesis of the novel 1,2,3,3a,4,5,6,11‐octahydro‐6,11a‐methano‐11aH‐benzo[4,5]cycloocta[1,2‐c]‐pyrrole system by acid‐catalyzed cyclization of cis‐3a‐benzyl‐3a,4,7,7a‐tetrahydro‐1H‐isoindole‐1,3(2H)‐diones is described.
Preparation and spectroscopic properties of 3‐acyl‐1,3,4‐oxadiazolines
Authors: Hearn Michael J. , Chanyaputhipong Phet‐Yoon 
Published: March 2009

Abstract1,3,4‐Oxadiazolines I, in which substituent groups R1 through R4 may be varied through appropriate choice of precursor reactants, can be prepared in good yields and purity by convenient cyclizations of acyl‐hydrazones with anhydrides. The reactions can be effectively monitored by salient changes in the infrared spectra. The oxadiazolines are stable materials and thus serve as suitable derivatives for the chemical characterization of such tuberculostatic Schiff bases as IIa‐c.
Synthetic studies of two new condensed 1,3,5‐triazinium compounds of expected biological activity
Authors: Okide George B. 
Published: March 2009

AbstractTwo new triazinium perchlorates, 1 and 2, readily lose perchloric acid, especially in the presence of a base to afford the corresponding anhydrobases. These are easily methylated but the product from 1 appears not to retain the original electronic configuration.
Structures and fluorescence of secondary products produced from the cope‐knoevenagel reaction of 2‐phenylpropionaldehyde with methyl cyanoacetate
Authors: Nagai Wakatu , Hirata Yumiko , Kawai Masao , Tanaka Kiyoaki 
Published: March 2009

AbstractThe Cope‐Knoevenagel reaction of 2‐phenylpropionaldehyde (7) with methyl cyanoacetate (8) produced methyl (E)‐2‐cyano‐4‐phenylpent‐2‐enoate (9) and the two highly fluorescent secondary products, 2‐amino‐3‐carbomethoxy‐6‐phenyl‐4‐(1‐phenylethyl)pyridine (10) and 3‐cyano‐6‐phenyl‐4‐(1‐phenylethyl)‐2‐pyridone (11). The structure of 10 was determined by X‐ray crystallography while the structure of 11 was confirmed by the conversion of 9 into 11. The mechanism of their formation is discussed. Fluorescence of 10 and 11 and the related compounds are also described.
Synthesis and characterization of α,α'‐bis(aminomethyl)oligothiophenes and their related compounds
Authors: Muguruma Hitoshi , Saito Takashi , Sasaki Satoshi , Hotta Shu , Karube Isao 
Published: March 2009

AbstractWe have synthesized and characterized a series of novel compounds of α,α'‐bis(arninomethyl)oligothiophenes and their related compounds whose degree of polymerization spans two (dimer) to five (pentamer). The compounds presented in our studies are α,α'‐bis[(2,2,5,5‐tetramethyl‐1‐aza‐2,5‐disilacyclopenthyl)methyl]oligothiophene, α,α'‐bis(aminomethyl)oligothiophene dihydrochloride and α,α'‐bis(aminomethyl)oligothiophene. These compounds exhibit desired chemical activity while maintaining controllable electronic properties. The synthetic processes of the oligothiophenes are as follows: 2‐aminomethylthiophene is first ‘protected’ and the thiophene rings are coupled using standard Grignard methods. The protected groups are removed at the final stage of the reaction. The compounds show unique properties; for example α,α'‐bis(aminomethyl)oligothiophene dihydrochloride is soluble in water. The results of electronic spectra and titration are also presented.
Synthesis of 2H‐labeled alkoxyethyl phosphodiester (AZT) derivatives for solid‐state 2H‐NMR studies
Authors: Koufaki M. , Calogeropoulou T. , Mavromoustakos T. , Theodoropoulou E. , Tsotinis Andrew , Makriyannis Alexandras 
Published: March 2009

AbstractTwo specifically 2H‐labeled alkoxyethyl phosphodiester AZT derivatives 9 and 14 were synthesized. Pilot [2H]‐solid‐state nmr experiments on conjugate 14 demonstrated their usefulness in studying interactions with model or biological membranes.
Computational studies, synthesis and biological investigations of N‐[(p‐bromo)carboxyphenyl]dibenz[b,f]azepine
Authors: Martínez Roberto , Espinosa Rubén C. , Toscano Rubén A. , Cogordán J. Antonio , Arellano María Del Rosario , Angeles Enrique , Posada María Eugenia , Maya Beatriz , Martínez Luisa 
Published: March 2009

AbstractWith the aim to find new compounds with superior tranquilizer‐antidepressant activity theoretical studies, synthesis, X‐ray characterization and pharmacological test of the title compound were carried out. Theoretical studies suggested both tranquilizer and antidepressant activity and pharmacological tests proved it.
Synthesis and total 1H‐NMR assignment of [1]benzothieno‐[2,3‐c] [1,10]phenanthroline
Authors: Halverson Aileen Pfleider , Castle Lyle W. 
Published: March 2009

AbstractThe synthesis of [1]benzothieno[2,3‐c][1,10]phenanthroline (5) is described. It was obtained in four steps from known starting materials. The basic skeleton of the molecule and of the phenanthroline ring were formed via photocyclization. The total assignment of 1H‐nmr spectra was accomplished with the aid of two‐dimensional nmr methods.
Synthesis of 2‐(ω‐aminoalkyl)imidazolin‐4‐ones by ring chain transformation of lactam derivatives with α‐aminoamides
Authors: Rottmann Antje , Liebscher Jürgen 
Published: March 2009

AbstractReaction of N‐methylamides of biogenic (S)‐α‐amino acids 3 with lactam acetals 1 or lactim ethers 2 gives three types of products, i.e. N‐methyl‐α‐lactamiminoamides 5 by condensation, 2‐(ω‐aminoalkyl)imidazolin‐5‐ones 7 or 2‐(ω‐lactamimmoalkyl)imidazolin‐4‐ones 8 by ring chain transformation. All products represent novel optically active derivatives of biogenic α‐aminoacids.
Synthesis of flavone‐3‐sulfonylureas
Authors: Löwe Werner , Matzanke Norbert 
Published: March 2009

AbstractThe synthesis of new flavone‐3‐sulfonylurea derivatives is hereby described. The influence of a phenyl group in the 2‐position and an acetate group in the 8‐position at the chromone nucleus on the activity was studied. Only weak cytostatic activity of the new compounds was found.
The cycloaddition of diethyl chlorophosphite with norbornadiene: Synthesis and crystal structure of the cycloadduct.
Authors: Roussis Vassilios , Bænziger Norman C. , Wiemer David F. 
Published: March 2009

AbstractIn the presence of Lewis acids, diethyl phosphorochloridite reacts with norbornadiene to afford the tetracyclic phosphinate ester 3. The reaction is believed to involve formation of phosphenium ions stabilized only by alkoxy substituents. The cycloadduct of the reaction was characterized by its spectral data, by single crystal diffraction analysis of the parent acid, and 31P and 27Al nmr experiments.
Photocyclization of 2‐(naphth‐1‐yl)‐3‐(thien‐2‐yl)propenoic acid and the total assignment of the 1H‐ and 13C‐NMR spectra of the product
Authors: Tominagaxs Yoshinori , Castle Lyle W. , Castle Raymond N. 
Published: March 2009

AbstractPhotocyclization of the substituted 2‐(naphth‐1‐yl)‐3‐(thien‐2‐yl)propenoic acid (3) in the presence of iodine and air in a benzene‐cyclohexane mixture afforded a separable mixture of three compounds, phenanthro[2,1‐b]thiophene‐10‐carboxylic acid (4), phenanthro[2,1‐b]thiothene (5), and naphtho[1,8‐cde]‐thieno[3,2‐g][2]benzopyran (6)
Reactions of 2‐amino‐, 2‐alkylamino‐, and 2‐piperidino‐1‐azaazulenes with aryl and chlorosulfonyl isocyanates
Authors: Abe Noritaka , Matsuda Haruhiko , Sugihara Yoshikazu , Kakehi Akikazu 
Published: March 2009

AbstractReaction of 2‐amino‐1‐azaazulene with phenyl isocyanate gave 3‐phenyl‐2H‐3,4‐dihydro‐1,3,4a‐triazabenz[5,4‐a]azulene‐2,4‐dione. Reactions of 2‐alkylamino‐1‐azaazulenes with aryl isocyanates gave 2‐(N‐ethyl‐N′‐arylureido)‐1‐azaazulenes initially, which rearranged to N‐aryl‐2‐alkylamino‐1‐azaazulene‐3‐carboxamides and successive reaction with another molar amount of aryl isocyanate furnished uracil‐fuzed 1‐azaazulenes. Reaction of 2‐piperidino‐1‐azaazulene with aryl isocyanate gave N‐aryl‐2‐piperidino‐1‐azaazulene‐3‐carboxamide. Reaction of 2‐(substituted amino)‐1‐azaazulenes with chlorosulfonyl isocyanate gave 3‐cyano‐ and 3‐chloro‐2‐(substituted amino)‐1‐azaazulenes.
An AM1 and DFT‐AM1 computational study of methyl phenylpropiolate addition to 1‐phenyl‐3,4‐dimethylphosphole
Authors: Jursic Branko S. , Leblanc Blaise 
Published: March 2009

AbstractThe transition state structures for the addition of maleic acid anhydride and methyl phenylpropiolate to 1‐phenyl‐3,4‐dimethylphosphole were generated with the AM1 semiempirical method. The competitive transition state structures for 1,5‐phenyl rearrangement in 1‐phenyl‐3,4‐dimethylphosphole was also optimized with AM1. The energies were evaluated with the SVWN and Becke3LYP DFT methods using a 6‐31G(d) basis set. The reaction outcome based on the evaluated energies were discussed and compared with experimental observations.
Synthesis of an indole analog of magallanesine via the [1,2]‐meisenheimer rearrangement
Authors: Yoneda Ryuji , Kimura Tetsuya , Kinomoto Junko , Harusawa Shinya , Kurihara Takushi 
Published: March 2009

AbstractRing expansion of azetopyridoindole 11 via the [1,2]‐Meisenheimer rearrangement of the corresponding N‐oxide 12 gave azocinoindole 14, which was converted into the N‐benzoylenaminone 18 in 5 steps. Intramolecular cyclization of 18 was accomplished by a modified Heck reaction followed by reductive desulfonylation to provide the indole analog 2, 5H‐isoindolo[2′,1′;1,2]azocino[5,6‐b]indole, of magallanesine 1.
An electron‐impact mass spectral (EIMS) study of N‐1 and C‐6 carboxyalkyl‐ and alkoxycarbonylalkyl‐substituted derivatives of uracil
Authors: Wyrzykiewicz E. , Kazimierczuk Z. 
Published: March 2009

AbstractThe electron impact (EI) induced mass spectral fragmentation of seventeen, including seven newly synthesized, N‐1 and C‐6 carboxyalkyl‐ and alkoxycarbonylalkyl‐substituted derivatives of uracil and thymine was investigated. Fragmentation pathways are proposed on the basis of accurate mass and metastable transition measurements. The correlation between the intensities of the M+* and selected fragment ions of these compounds is discussed. The data obtained provide the basis for distinguishing isomers and metamers.
Synthesis of oxazolyl‐ and furanyl‐substituted imidazole hydrochlorides and methiodides
Authors: Boulos John , Schulman Jerome 
Published: March 2009

AbstractOxazolyl‐5‐ and furanyl‐2‐substituted imidazoles have been synthesized by coupling the two ring systems via the dipolar cycloaddition of tosyl methyl isocyanide to the corresponding oxazolyl and furanyl aldimines in basic media. These substituted oxazolyl and furanylimidazole bases obtained in this manner were then subjected to hydrogen chloride gas and to methyl iodide to form the corresponding hydrochlorides and methyliodides, respectively. All compounds were purified, characterized and then tested for muscarinic binding affinity. Biological test results revealed low muscarinic receptor affinity and selectivity.
Retro‐ene reactions in heterocyclic synthesis. IV. A new synthetic method for 6‐hydroxypyrimidin‐4(3H)‐ones and 1,3,5‐triazine‐2,4(1H,3H)‐diones
Authors: Ito Kunio , Miyajima Shingo 
Published: March 2009

AbstractN‐t‐Butylbenzamidines 1 reacted with diphenyl phenylmalonate or diphenyl methylmalonate to give 6‐hydroxypyrimidin‐4(3H)‐ones 4 or 5. Amidines 1 on reaction with diphenyl imidodicarboxylate afforded 1,3,5‐triazine‐2,4(1H, 3H)‐diones 8.
New syntheses of 7‐substituted‐2‐aminothieno‐ and furo[3,2‐d]pyrimidines
Authors: Morris Philip E. , Elliott Arthur J. , Montgomery John A. 
Published: March 2009

AbstractIn a recent publication, we have the described the synthesis of 7‐substituted‐2‐amino‐1,5‐dihydro‐4H‐pyrrolo[3,2‐d]pyrimidin‐4‐ones which are potent inhibitors of the enzyme Purine Nucleoside Phosphorylase from the corresponding 3‐aminopyrroIe‐2‐carboxylate esters. A key step in the synthesis is condensation of the amino group with the highly reactive guanylating reagents 3 or 4 followed by annulation. The furo[3,2‐d]pyrimidin‐4‐one and thieno[3,2‐d]pyridin‐4‐one are closely related rings systems. However, these rings have not been reported in the literature with a 2‐amino, substituent which would arise from such guanylation reactions. In this report, the syntheses of the novel furans 5 are described based on our improved pyrrole synthesis (Scheme 1). The syntheses of the novel thiophenes 6 are described. The guanylation of 5 and 6 were studied and compared to 2. The 3‐amino group of 5 and 6 failed to react with 3 or 4 under mild acid catalysis; conditions under which 2 easily condensed. Guanylation was finally achieved by generating the carbodiimide intermediate of 3 under mercury catalysis affording the guanylated adducts which were converted to the novel 2‐aminothieno‐ and furo[3,2‐d]pyrimidin‐4‐ones 16.
Synthesis and biological activity of 1‐, 2‐ or 3‐Substituted benzothieno‐[2,3‐d]triazole derivatives structurally related to trazodone
Authors: Guerrera Francesco , Salerno Loredana , Sarvà Maria Concetta , Siracusa Maria Angela , Corsaro Antonino , Pistarà Venerando , Capasso Raffaele , Raso Giuseppina Mattace 
Published: March 2009

AbstractA series of new 1‐, 2‐ and 3‐piperazinylbenzothieno[2,3‐d]triazole derivatives structurally related to Trazodone were prepared and tested for their antiserotonergic, antiadrenergic and antihistaminergic in vitro activities together with their analgesic in vivo activity by using Trazodone as the reference compound.
Regiospecific synthesis of 2‐substituted furanonaphthoquinones
Authors: Ohta Yasuo , Doe Matsumi , Morimoto Yoshiki , Kinoshita Takamasa 
Published: March 2009

AbstractThe naturally‐occurring furanonaphthoquinones 1a‐d have been synthesized from 3‐furancarboxylic acid and 2,3‐dimethoxybenzaldehyde via the Birch reduction‐elimination.