bluuebunny/crossref_metadata_2025_split huggingface dataset:
Acetylenic chemistry: Part15[1]. Reactions of 1,2,3,4‐Tetrahydro‐2,4‐dioxopyrido[2,3‐d]pyrimidine with 3‐bromoprop‐1‐yne
Authors: Reisch J. , Usifoh [2] C. O. , Oluwadiya J. O. 
Published: March 2009

AbstractReaction of 1,2,3,4‐tetrahydro‐2,4‐dioxopyrido[2,3‐d]pyrimidine with 3‐bromoprop‐1‐yne gave 1‐prop‐2′‐ynylpyrido[2,3‐d]pyrimidine‐2,4‐dione (4a), 3‐prop‐2′‐ynylpyrido[2,3‐d]pyrimidine‐2,4‐dione (4b), and 1,3‐diprop‐2′‐ynylpyrido[2,3‐d]pyrimidine‐2,4‐dione (4c). Subsequent boiling of 1,3‐diprop‐2′‐ynylpyrido‐[2,3‐d]pyrimidine‐2,4‐dione (4c) in formic acid afforded 1‐methylimidazo[1,2‐a]pyridyl‐N‐prop‐2′‐ynylamide (5) and 1‐acetonyl‐3‐prop‐2′‐ynylpyrido[2,3‐d]pyrimidine‐2,4‐dione (6).
Functionalized di‐ and tetrathia‐crowns and their use to quantitatively separate and recover gold(III), palladium(II), silver(I) and mercury(II) Ions
Authors: Bradshaw Jerald S. , Krakowiak Krzysztof E. , Izatt Reed M. , Bruening Ronald L. , Tarbet Bryon J. 
Published: March 2009

AbstractTwo new dithia‐crowns containing a hydroxy group and 1,4,7,10‐tetrathia‐18‐crown‐6 containing an allyl‐oxymethyl substituent were prepared in good yields. Two of these crowns were covalently attached to silica gel. The silica gel‐bound thia‐crowns were used to separate gold(III), palladium(II), silver(I) and mercury(II) ions from an aqueous 0.1 M nitric acid solution which also contained 1.0 M ferric chloride.
Michael additions to acrylonitrile, methyl acrylate and methyl vinyl ketone to Nb‐benzylidenetryptophan methyl ester
Authors: Braña Miguel F. , Garrido Mercedes , López Rodríguez María L. , José Morcillo M. 
Published: March 2009

AbstractMichael addition to methyl acrylate and methyl vinyl ketone of Nb‐benzylidene‐L‐tryptophan methyl ester 1 gave 2‐(3‐indolylmethyl)glutamic dimethyl ester 2a and α‐(3‐oxobutyl)tryptophan methyl ester 2b respectively. Addition to acrylonitrile of 1 yielded α,Na‐dicyanoethyltryptophan methyl ester 3.
Pyridazines with heteroatom substituents in positions 3 and 5. 6. SN reactions in position 5 of 2‐aryl‐5‐hydroxypyridazin‐3(2H)‐ones
Authors: Schober Bernt D. , Megyeri Gabor , Kappe Thomas 
Published: March 2009

AbstractThe nucleophilic introduction of chloro‐ (2), azido‐ (4), (substituted) amino (3, 6), mercapto (10) and hydrazino‐groups (13) into 2‐aryl‐5‐hydroxypyridazin‐3(2H)‐ones [3] is described. The 5‐aminopyridazin‐3(2H)‐one (6) also reacts with activated malonates 8 [4] to give pyrido[2,3‐d]pyridazines 9. Hydrazino compounds 13 can be treated with aldehydes to yield compounds 14. Iodine can be introduced into position 4 of 5‐amino‐(15) and 5‐hydroxypyridazin‐3(2H)‐ones (17) by electrophilic substitution to afford compounds 18.
A simple synthesis of novel 2‐pyridones from chalcones
Authors: Al‐Arab Mohammad M. 
Published: March 2009

AbstractSeveral novel 2‐pyridones were synthesized in good yields from a simple one‐pot reaction by the condensation of different substituted chalcones and malonamide using sodium ethoxide in ethanol at room temperature. The structures of these 2‐pyridones were elucidated from their 1H, 13C and infrared spectral data as well as their elemental analysis. Different 2‐pyridones tautomers were obtained as the solvent of crystallization changes.
Sels de N‐alcoxyquinoléinium et de N‐alcoxyisoquinoléinium porteurs d'une fonction ester dans leur chaine alcoxyle: Synthèse et réactivité vis‐a‐vis des ions cyanure
Authors: Sliwa Henri , Randria‐Raharimanana Clarisse , Ouattara Lassina 
Published: March 2009

AbstractReaction of ethyal α‐bromoisobutyrate on quinoline 1‐oxide and isoquinoline 2‐oxide in the presence of silver perchlorate leads to the corresponding N‐alkoxyl salts 1 and 2. On treatment with potassium cyanide, these salts are converted into 2‐cyanoquinoline and 1‐cyanoise‐quinoline according to mode B of the Katritzky' s classification concerning the reaction of nucliophiles on N‐alkoxypyridinium salts. When the reaction of cyanide ions were performed on salt 1 at 0° in aqueous solution the dihydro aromatic 4 was isolated. This result confirms the addition‐elimination mechanism of the reaction studied.
2‐Methylpyridinium salts as 1,4‐dinucleophiles. IV. Westphal condensation with 2‐alkyl‐1‐aminoazinium substrates
Authors: Matia M. Paz , Navío J. Luis Garcia , Vaquero J. José , Alvarez‐Builla J. 
Published: March 2009

AbstractCondensation of 2‐alkyl‐1‐aminopyridinium, quinolinium or 1‐alkyl‐2‐aminoisoquinolinium salts with 1,2‐acenaphthenequinone or 9,10‐phenanthrenequinone in the presence of base, gave pyrido[1,2‐b]pyridazinium salts in good yields.
The preparation of 5‐substituted thieno[2,3‐b]furan‐2‐sulfonamides
Authors: Hartman George D. , Halczenko Wasyl , Prugh John D. , Williams Theresa M. 
Published: March 2009

AbstractAn efficient synthetic route is reported for the preparation of thieno[2,3‐e]furan‐2‐sulfonamides bearing oxygenated functionality at C‐5. The method employs conversion of furan‐3‐carboxaldehyde to an intermediate that, in the key step, undergoes facile cyclodehydration to the fused [5,5] heterocycle under mild Knoevenagel conditions.
Synthesis of new derivatives of β‐carboline‐hydantoin
Authors: Braña Miguel F. , Garrido Mercedes , Rodriguez María L. López , Miguel Pilar , Morcillo M. José , Riaño A. 
Published: March 2009

AbstractReaction of tetrahydro‐β‐carboline‐3‐carboxylic acids 4a‐c with alkyl and phenyl isocyanates in acetone provide the corresponding 2,5‐disubstituted 1,3‐dioxo‐6H‐1,2,3,5,11,11a‐hexahydroimidazo[1,5‐b]‐β‐carbolines 2a‐r.
The crystal and molecular structure of 5‐N‐methyl‐β‐d‐arabinofurano[1′,2′:4,5]oxazolo‐S‐triazine‐4,6‐dione: Molecular modeling studies on the pattern of alkylation of β‐D‐arabinofurano[1′,2′:4,5]oxazolo‐s‐triazin‐4‐one‐6‐thione
Authors: Purkayastha Subhasish , Cheer Clair J. , Panzica Raymond P. 
Published: March 2009

AbstractThe involvement of the 5′‐hydroxyl group on β‐D‐arabinofurano[1′,2′:4,5]oxazolo‐s‐triazin‐4‐one‐6‐thione (1b), to form an intramolecular covalent adduct at C6, is postulated to explain the formation of almost equal amounts of 5‐N‐alkyl‐β‐D‐arabinofurano[1′,2′:4,5]oxazolo‐s‐triazin‐4‐one‐6‐thione and 5‐N‐alkyl‐β‐D‐arabinofurano[1′,2′:4,5]oxazolo‐s‐triazine‐4,6‐dione during alkylation of 1b. An X‐ray crystallographic study was conducted on 5‐N‐methyl‐β‐D‐arabinofurano[1′,2′:4,5]oxazolo‐s‐triazine‐4,6‐dione (2a) and its solid state structure was established. This was compared to the energy minimized structure of the same compound that was generated by the molecular modeling program, MACROMODEL. Force field calculations (Allinger's MM2) on this structure and other intermediates lend support to the concept of formation of the intramolecular covalent adduct.
A facile synthesis of certain 4‐ and 4,5‐disubstituted 1‐β‐d‐ribofuranosylpyrazoles
Authors: Bhattacharya Birendra K. , Robins Roland K. , Revankar Ganapathi R. 
Published: March 2009

AbstractA number of pyrazole ribonucleosides, structurally related to AICA riboside and ribavirin have been prepared and evaluated for their biological activity in vitro. Deisopropylidenation of 5‐amino‐1‐(2,3‐O‐isopropylidene‐β‐D‐ribofuranosyl)pyrazole‐4‐carbonitrile (6) with aqueous trifluoroacetic acid gave 5‐amino‐1‐(β‐D‐ribofuranosyl)pyrazole‐4‐carbonitrile (7). Conventional transformation of the carbonitrile function of 7 gave the AICA riboside congener (2) and related 5‐amino‐1‐(β‐D‐ribofuranosyl)‐pyrazoles (8–10). Acetylation of 7 at low temperature gave the versatile intermediate 5‐amino‐1‐(2,3,5‐tri‐O‐acetyl‐β‐D‐ribofuranosyl)pyrazole‐4‐carbonitrile (15). Non‐aqueous diazotization of 15 with isoamylnitrite in dibromomethane or diiodomethane gave the corresponding C5‐bromo 13 and C5‐iodo 16 derivatives. Compounds 13 and 16 were subsequently transformed into 5‐bromo‐1‐(β‐D‐ribofuranosyl)pyrazole‐4‐carboxamide (11) and the 5‐iodo analog 25. However, a similar nonaqueous diazotization of 15 in dichloromethane afforded the deaminated product 1‐(2,3,5‐tri‐O‐acetyl‐β‐D‐ribofuranosyl)pyrazole‐4‐carbonitrile (22). Treatment of 22 with ammonium hydroxide/hydrogen peroxide gave the ribavirin congener 1‐(β‐D‐ribofuranosyl)pyrazole‐4‐carboxamide (18). Similar treatment of 22 with hydrogen sulfide in pyridine or hydroxylamine in ethanol gave the 4‐thiocarboxamide 19 and 4‐carboxamidoxime 20 derivatives, respectively. Catalytic hydrogenation of 20 afforded 1[β‐D‐ribofuranosyl)pyrazole‐4‐carboxamidine (21). These pyrazole nucleosides are devoid of any significant antiviral or antitumor activity in vitro.
A new synthesis of dl‐5‐vinyloxazolidine‐2‐thione, a natural antithyroid factor
Authors: Gardrat C. , Latxague L. , Picard J. P. 
Published: March 2009

AbstractA new procedure for the preparation of DL‐5‐vinyloxazolidine‐2‐thione (goitrin) 3 via a facile and practical synthesis of the key intermediate DL‐1‐amino‐3‐buten‐2‐ol 2 is described.
Temperature‐dependent reaction of 1,4,6‐triaminopyrimidine‐2(1H)‐thiones with vilsmeier reagent. formation of [1,2,4]triazolo[1,5‐c]pyrimidin‐5(6H)‐ones
Authors: Tsuji Tadakazu , Takenaka Keiko 
Published: March 2009

Abstract5,7‐Diamino[1,3,4]thiadiazolo[3,2‐a]pyrirnidinium chloride 2, 7‐amino[1,2,4]triazolo[1,5‐c]pyrimidine‐5(6H)‐thiones 3 and the 5(6H)‐one derivative 4a were synthesized by the reaction of 1,4,6‐triaminopyrimidine‐2(1H)‐thione 1 with phosphoryl chloride and N,N‐dimethylacylamides. Further, compounds 4 were prepared from 2, 3 or 1,4,6‐triaminopyrimidin‐2(1H)‐one 6 by the treatment with the above reagents. Compounds 3 and 4 were converted to 7‐amino[1,2,4]triazolo[1,5‐c]pyrimidin‐5(6H)‐ones 5.
Heterocyclic photorearrangements. Photoinduced rearrangement of 3‐styryl‐1,2,4‐oxadiazoles
Authors: Buscemi Silvestre , Cusmano Giuseppe , Gruttadauria Michelangelo 
Published: March 2009

AbstractThe photochemical behaviour of 3‐styryl‐5‐phenyl‐(5‐methyl)‐1,2,4‐oxadiazoles in methanol at 254 nm has been investigated. A photoinduced rearrangement to the quinoline system has been pointed out and explained as proceeding through an initial photolysis of the ring ON bond, followed by a six membered ring closure reaction involving the styryl moiety.
An approach towards the synthesis of 4‐phenyl‐5‐arylimino‐δ2‐1,2,3,4‐thiatriazolines
Authors: L'Abbé Gerrit , Franek Walter , Toppet Suzanne , Delbeke Pieter 
Published: March 2009

Abstract4‐Phenyl‐5‐arylimino‐δ2‐1,2,3,4‐thiatriazolines are presumably formed by reacting 5‐arylaminothiatriazoles with benzyne at 50°, but decompose in situ to benzothiazole derivatives by way of the two pathways (a) and (b) shown in Scheme 4.
One‐step methods to prepare cryptands and crowns containing reactive functional groups
Authors: Krakowiak Krzysztof E. , Bradshaw Jerald S. , Izatt Reed M. 
Published: March 2009

AbstractA one‐step synthesis of cryptand [2.2.2] containing three methylenyl substituents in a 25% yield from the reaction of triethanolamine and 3‐chloro‐2‐chloromethyl‐1‐propene is described. A similar cryptand was prepared in 56% yield by a two‐step process. One‐step syntheses of N,N‐hydroxyethyl‐diaza‐18‐crown‐6 and crown‐6 compounds containing two alkene functional groups are also described.
Synthesis of 3,4,6‐trisubstituted cinnolines by intramolecular wittig reaction of ortho‐carbonyl substituted arylazomethylenetriphenylphosphoranes
Authors: Licandro Emanuela , Maiorana Stefano , Papagni Antonio , Tarallo Daniele , Slawin Alexandra M. Z. , Williams David J. 
Published: March 2009

AbstractThis paper reports the first example of Wittig reaction on arylazomethylenetriphenylphosphoranes, producing the new cinnolines 6 and 7. A new unexpected rearrangement reaction producing quinoline 8 is also reported. The structure of compound 8 was determined by X‐ray analysis.
A New method for the synthesis of 4‐oxo‐4,5‐dihydrofuro[3,2‐c]quinoline
Authors: Gronowitz Salo , Timari Géza 
Published: March 2009

AbstractA new method for the synthesis of 4‐oxo‐4,5‐dihydrofuro[3,2‐c]quinoline is the Pd(0)‐catalyzed coupling of o‐bromonitrobenzene with 3‐formyl‐2‐tributylstannylfuran, followed by reductive ring closure to furo[3,2‐c]quinoline N‐oxide and rearrangement.
Annelated piperazinyl‐7,8‐dihydro‐6H‐thiopyrano[3,2‐d]pyrimidines
Authors: Wu M. T. , MacCoss M. , Ikeler T. J. , Hirshfield J. , Arison B. H. , Tolman R. L. 
Published: March 2009

AbstractTricyclic analogs of piperazinylthiopyrano[3,2‐d]pyrimidine hypoglycemic agents were prepared. The angular tricyclic systems, 8,9‐dihydro‐7H‐thiopyrano[2,3‐e][1,2,4]triazolo[4,3‐a]pyrimidine and 8,9‐dihydro‐7H‐tetrazolo[1,5‐a]thiopyrano[2,3‐e]pyrimidine derivatives were synthesized from 2,4‐dichloro‐7,8‐dihydro‐6H‐thiopyrano[3,2‐d]pyrimidine in three step sequences. Derivatives of the linear tricyclic system, 5,6‐dihydro‐7H‐thiopyrano[3,2‐d][1,2,4]triazolo[2,3‐a]pyrimidine, were prepared by condensation of 3‐amino‐1,2,4‐triazole with ethyl 3‐oxo‐tetrahydropyran‐2‐carboxylate. The tricyclic heteroaryl‐piperazines lacked significant hypoglycemic activity.
Polycyclic N‐hetero compounds. XXXIII. Syntheses of 4‐substituted 6,7‐dihydro‐5H‐benzo[6,7]‐cyclohepta[1,2‐d]pyrimidines and their inhibitory activities on platelet aggregation and on reserpine‐induced hypothermia
Authors: Sasaki Kenji , Hirota Takashi , Arimoto Yuichi , Satoh Yoshiko , Ohtomo Hiromi , Nakayama Taiji 
Published: March 2009

AbstractVarious 4‐substituted 6,7‐dihydro‐5H‐benzo[6,7]cyclohepta[1,2‐d]pyrimidines were synthesized by the reaction of 4‐chloro‐6,7‐dihydro‐5H‐benzo[6,7]cyclohepta[1,2‐d]pyrimidine with amines. Their inhibitory activities against collagen‐induced platelet aggregation and also against reserpine‐induced hypothermia in mice were investigated.
Heterocyclic X‐azolopyridine intermediates
Authors: Viscardi Guido , Savarino Piero , Barni Ermanno , Carpignano Rosarina 
Published: March 2009

AbstractA series of heterocyclic coupling agents having tuned hydrophobic chains, has been prepared by reaction of diamino or hydroxy‐aminopyridines and p‐aminosalicylic acid. The acetylation of amino group and hydroxyl in oxazole derivatives showed a selectivity depending on wheter acetic anhydride or acetyl chloride was used. Correlations between structure and spectroscopic data, including related compounds previously described, are reported.
Synthesis of tetra‐substituted furan derivatives from 1‐arylpropane‐2,3‐diones
Authors: Jones A. M. , Simpson A. J. , Stanforth S. P. 
Published: March 2009

Abstract1‐Arylpropane‐2,3‐diones 4 gave 2‐dimethylamino‐3‐formyl‐4‐chloro‐5‐arylfuran derivatives 7 in the Vilsmeier reaction.
Synthesis and proton NMR stereochemical study of 7,8,9‐substituted‐7,8‐dihydro‐4H,9H‐furo[2′,3′,4′:4,4a,5]‐naphth[2,1‐e][1,3]oxazin‐4‐ones
Authors: Sabie Rafa , Fillion Houda , Pinatel Henri , Fenet Bernard 
Published: March 2009

Abstract7,8,9‐Substituted‐7,8‐dihydro‐4H,9H‐furo[2′,3′,4′:4,4a,5]naphth[2,1‐e][1,3]oxazin‐4‐ones were stereospecifically obtained as a single pair of enantiomers. Their relative trans configuration and the conformation of the dihydro oxazine ring were established by 1H nmr 2D NOESY experiments.
Synthesis of pyrrolo[2,3‐d]pyrimidine ribosides and their potential in chemotherapeutics
Authors: Eger Kurt , Grieb Gerlinde , Spätling Sabine 
Published: March 2009

AbstractThe synthesis of a number of 5,6‐dimethylpyrrolo[2,3‐d)pyrimidines substituted in position7with ribose, deoxyribose, respectively and their acyclic analogues is described and their potential in chemotherapeutics was tested. None of the compounds showed remarkable biological effects.
Synthesis of novel acyclonucleosides. Reactions of 1‐(2‐oxopropyl)pyridazin‐6‐ones
Authors: Choi Sam‐Yong , Shin Sung Chul , Yoon Yong‐Jin 
Published: March 2009

AbstractMulti‐substituted‐1‐(1‐bromo‐2‐oxopropyl)pyridazin‐6‐ones 3, 4, multi‐substituted‐1‐(1,1‐dibromo‐2‐oxopropyl)pyridazin‐6‐ones 7, 8, and multi‐substituted‐1‐(3‐bromo‐2‐oxopropyl)pyridazin‐6‐ones 5, 6 were synthesized from the corresponding 1‐(2‐oxopropyl)pyridazin‐6‐ones 1, 2 by the selective bromination in acidic or neutral medium. And treatment of 1,1‐dibromo‐2‐oxopropyl derivatives 7, 8 with aqueous potassium carbonate gave the corresponding pyridazin‐6‐ones 9, 10 by the dealkylation. Reaction of 1 with methanolic potassium cyanide afforded only the corresponding 4‐methoxy derivative 11, whereas reaction of 2 with methanolic potassium cyanide gave 4‐methoxy derivative 12 and 2‐cyano‐2‐hydroxypropyl derivative 13. Reaction of 1 and 2 with hydroxylamine in methanol afforded the corresponding syn‐2‐hydroxyiminopropyl derivatives 14 and 15.
Cycloaddition‐elimination reactions of 4‐methyl‐5‐(substituted)‐imino‐Δ2‐1,2,3,4‐thiatriazolines with isocyanates
Authors: L'abbé Gerrit , Weyns Nancy , Sannen Ingrid , Delbeke Pieter , Toppet Suzanne 
Published: March 2009

Abstract4‐Methyl‐5‐(substituted)imino‐1,2,3,4‐thiatriazolines 1 (R2 ≠ Me) undergo cycloaddition‐elimination reactions with isocyanates to yield 4‐methyl‐5‐(substituted)imino‐1,2,4‐thiadiazolidine‐3‐ones 5 via the thermodynamically less stable isomers 4. The latter have not been isolated, except for 4q which was shown to iso‐merize rapidly into 5q with phenylsulfonyl isocyanate. The reactions of 1 are accelerated by using less bulky R2 substituents and more electrophilic isocyanates, in accordance with the viewpoint that 1 reacts as a masked 1,3‐dipole. The products 4i‐n (= 5i‐n), derived from 1b, add isocyanates reversibly to give 2,3,4,5‐tetrahydro‐6aλ4‐thia‐1,3,4,6‐tetraazapentalene‐2,5‐diones 9i‐n, which have been isolated and characterized spectroscopically. Such compounds with a hypervalent sulfur atom thus occur as intermediates during the isomerization of 4 to 5 under the influence of isocyanates.
Syntheses of dibenzo[c,e][1,2]diselenin and related novel chalcogenide heterocyclic compounds
Authors: Murata Shizuaki , Suzuki Toshiyasu , Yanagisawa Akira , Suga Seiji 
Published: March 2009

AbstractReaction of 2,2′‐dilithio‐1,1′‐binaphthyl with selenium followed by air oxidation gives a mixture of dinaph‐thoselenophene and dimer and oligomers of 2,2′‐diseleno‐1,1′‐binaphthyl. 2,2′‐Dilithio‐1,1′‐biphenyl reacts with selenium to afford dibenzo[c,e][1,2]diselenin. Structures of the dimeric 2,2′‐diseleno‐1,1′‐binaphthyl and dibenzo[c,e][1,2]diselenin have been confirmed by X‐ray crystallographic analyses. Similar reaction of 2,2′‐dilithio‐1,1′‐binaphthyl with sulfur or tellurium gives a mixture of dinaphthothiophene and dinaphtho[2,1‐c:‐1′,2′‐e][1,2]dithiin or a mixture of dinaphthotellurophene and oligomer of 2,2′‐ditelluro‐1,1′‐binaphthyl, respectively. Dibenzotellurophene and oligomer of 2,2′‐ditelluro‐1,1′‐biphenyl are obtained from reaction of 2,2′‐dilithio‐1,1′‐biphenyl with tellurium.
Study of the transformation products of the oxime of 2,7‐dioxo‐3‐methyl‐5‐phenyl‐2,3,5,6‐tetrahydrocyclopenta[f]benzoxazole
Authors: Barbry Didier , Couturier Daniel , Abdellatifi Noureddine , Lesieur Daniel , Lespagnol Charles 
Published: March 2009

AbstractBeckmann rearrangement of the title compound gave only a derivative of an isoquinoline structure and its catalytic hydrogenation afforded the cis isomer of 1‐amino‐3‐phenyl‐1,2‐dihydroindenes.
Synthesis of a phenylazo‐derivative of a 1,2,3‐thiadiazolium methylide. C‐13/N‐15 NMR characterization and crystal structure analysis
Authors: L'abbé Gerrit , Frederix Ann , Toppet Suzanne , Declercq Jean‐Paul 
Published: March 2009

AbstractThe N‐phenylhydrazone derived from 4‐methoxycarbonyl‐1,2,3‐thiadiazole‐5‐carbaldehyde 6 is methylated at the N‐3 position, yielding the mesoionic compound 8. The C‐13 and N‐15 nmr data, as well as the results from a crystal structure analysis, indicate that the molecule is best represented by the resonance forms 8A and 8B. Comparison is made with the previously synthesized thiadiazole derivative 2 which possesses thiapentalene characteristics.
Synthesis of 2‐aza analog of rosoxacin
Authors: Singh Baldev 
Published: March 2009

AbstractDiazotization of 2‐nitro‐4‐(4‐pyridinyl)aniline (4) in hydrobromic acid gave the corresponding bromo derivative 5 which was treated with cuprous cyanide to give the benzonitrile derivative 6 which in turn was converted to 2‐nitroacetophenone derivative 9. Reduction of 9 followed by diazotization of the resulting amine 10 gave 7‐(4‐pyridinyl)cinnolin‐4(1H)‐one (11) which was subsequently converted to 1‐ethyl‐1,4‐dihydro‐4‐oxo‐7‐(4‐pyridinyl)cinnoline‐3‐carboxylic acid (14) in three steps.
2‐Aryloxazolo[4,5‐b]‐ et [5,4‐b]pyridines: Synthèse et acylation par substitution radicalaire
Authors: Flouzat C. , Guillaumet G. 
Published: March 2009

AbstractLa synthèse de diverses 2‐aryloxazolo[4,5‐b]‐ et [5,4‐b]pyridines 2 et 4 est décrite, respectivement à partir du 2‐amino‐3‐pyridinol et de la 2‐chloro‐3‐aminopyridine. L'acylation par substitution radicalaire des composés ainsi formés est ensuite étudiée et permet d'accéder à différentes 5‐acyl ou 7‐acyl‐2‐aryloxazolo[4,5‐b]‐et [5,4‐b]pyridines, avec des rendements satisfaisants.
Synthesis and properties of a maleimide fluorescent thiol reagent derived from a naphthopyranone
Authors: Yang Jun‐Rui , Langmuir Margaret E. 
Published: March 2009

AbstractN‐(2‐Carbomethoxy‐9‐methoxy‐3‐oxo‐3H‐naphtho[2,1‐b]pyran‐10‐yl)maleimide 2 was designed and synthesized as a new maleimide fluorescent thiol reagent. The optical properties of 2 were investigated with and without the addition of glutathione, GSH. We have found 2 is twice as sensitive as DACM and is of comparable sensitivity to CPM for detection of thiols. The emission maximum for the GSH adduct of 2 is 513 nm which is at longer wavelength than the GSH adducts of both DACM and CPM.
Synthesis of 3,5‐disubstituted 1,2,4‐triazoles containing trimethoxyphenyl groups: Potential antagonists of platelet activating factor
Authors: Ares Jeffrey J. , Messier Renee J. , Kornecki Elizabeth 
Published: March 2009

AbstractIn an effort to develop a new class of Platelet Activating Factor antagonists, 3,5‐disubstituted 1,2,4‐triazoles containing trimethoxyphenyl groups have been synthesized. The synthesis of symmetrical triazoles5and6, as well as two methods of synthesizing unsymmetrical triazole7, are reported.
The stereochemical investigation of 8‐membered 1,3,6‐dioxazocines viaNMR
Authors: Nishiyama Tomihiro , Iwasaki Yoshiaki , Nishikawa Takeshi , Miyatake Shinji , Yamada Fukiko 
Published: March 2009

AbstractThe stereochemical properties of 2‐, 4‐, 7‐, and 8‐methyl substituted 5,6,7,8‐tetrahydro‐1,3,6‐dioxazocines have been investigated by their pmr and cmr spectroscopy. On the basis of the coupling constant and γ‐effects, the stereochemical structures are discussed.
Reaction of 4,5‐diamino, 5‐amino‐4‐glucosylamino and 4‐amino‐5‐glucosylaminopyrimidines with nitrous acid. synthesis, anticancer and anti‐aids activities of 8‐azapurines
Authors: Nogueras M. , Melguizo M. , Quijano M. L. , Sánchez A. 
Published: March 2009

AbstractThe reaction of the 4,5‐diamino, 5‐amino‐4‐glucosylamino and 4‐amino‐5‐glucosylaminopyrimidines 3a, 3b, 3c and 4 with nitrous acid is described. The 8‐azapurines 7a, 7c, 8 and the N‐nitrosoamino derivative 5 have been obtained. Some of these products were tested for anticancer and anti‐AIDS activity.
Synthesis and fluorescent properties of some heterobifunctional and rigidized 7‐aminocoumarins
Authors: Besson T. , Coudert G. , Guillaumet G. 
Published: March 2009

AbstractHeterobifunctional fluorescent reagents of coumarin type are synthesized. They possess, in position 7, a rigidized or un‐rigidized amino group and, in position 3 or 4, a carboxylic function. The fluorescence characteristics of these compounds are described and compared with the 7‐amino‐4‐methylcoumarin. The influence of the relative freedom of rotation of the amino group or the position of the acid function on the fluorescence properties are also studied.
Synthesis of 1,3‐benzodioxoles, 1,3‐benzoxathioles and 1,3‐benzodithioles from allenic derivatives
Authors: Cabiddu Salvatore , Cadoni Enzo , Ciuffarin Ennio , Fattuoni Claudia , Floris Costantino 
Published: March 2009

AbstractBenzo‐condensed five‐membered heterocyclic rings containing two heteroatoms have been synthesized starting from disubstituted benzenes and allenic derivatives. The structure of all products was corroborated by elemental analysis and ir and 1H nmr spectroscopy.