bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and antiviral evaluation of some novel [1,2,4]triazolo[4,3‐β][1,2,4]triazole nucleoside analogs
Authors: Jois Y. H. R. , Kwong C. D. , Riordan J. M. , Montgomery J. A. , Secrist J. A.
Published: March 2009

Ribosylation of 3‐amino‐5H‐[1,2,4]triazolo[4,3‐b][1,2,4]triazole (1) with l‐O‐acetyl‐2,3,5‐tri‐O‐benzoyl‐D‐ribofuranose and stannic chloride resulted in the following protected nucleoside analogs: 3‐amino‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)[1,2,4]triazolo[4,3‐β][1,2,4]triazole (4), 3‐amino‐1‐(2,3,5‐tri‐O‐benzoyl‐α‐D‐ribofuranosyl)[1,2,4]triazolo[4,3‐β][1,2,4]triazole (5), 3‐amino‐1‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl)[1,2,4]triazolo[4,3‐β][1,2,4]triazole (5), and 3‐(2,3,5‐tri‐O‐benzoyl‐β‐D‐ribofuranosyl) amino‐5H‐[1,2,4]triazolo[4,3‐b]‐[1,2,4]triazole (7). Compounds 4–6 were deprotected to 3‐amino‐1‐β‐D‐ribofuranosyl[1,2,4]triazolo[4,3‐b][1,2,4]‐triazole (3), 3‐amino‐1‐α‐D‐ribofuranosyl[1,2,4]triazolo[4,5‐b][1,2,4]triazole (8), and 3‐imino‐2H‐2‐β‐D‐ribo‐furanosyl[1,2,4]triazolo[4,3‐b][1,2,4]triazole (9), while 7 could not be deprotected without decomposition. Compounds 1, 4, 6, 7, and 9 were screened and found to have no antiviral activity.
Mesoionic dimethyl derivatives of some 1,2,4‐triazinones. The course of the reaction of 3,5‐dimethoxy, 3‐methoxy‐5‐methylthio, 5‐methoxy‐3‐ methylthio and 3,5‐bis(methylthio)‐1,2,4‐triazine with methyl iodide
Authors: Pískala Alois , Gut Jiří , Fiedler Pavel , Masojídková Milena , Šaman David , Liboska Radek
Published: March 2009

Treatment of 3,5‐dimethoxy‐1,2,4‐triazine (1a) with methyl iodide was found to give depending on the reaction time triazinium iodide 2a, triaziniumolates 4a and 6a as well as methoxytriazinones 7a and 8a. Thermolysis of 2a gave triaziniumolates 4a and 6a. Reaction of 2a, 4a or methoxytriazinone 9a with methyl iodide in acetonitrile yielded as the sole product 6a. Reaction of 3‐methoxy‐5‐methylthio‐1,2,4‐tri‐azine (1b) with methyl iodide gave triazinium iodide 2b and methylthio triazinone 7b. Hydrolysis of 2a,b afforded 4a. Reaction of 5‐methoxy‐3‐methylthio‐1,2,4‐triazine (1c) with methyl iodide gave triazinium iodide 2c, triaziniumolate 4b, triazinium iodide 5b and triazinone 8b. Hydrolysis of 2c yielded 4b and its thermolysis gave a mixture of 4b and 5b. Reaction of 2c, 4b and triazinone 9b with methyl iodide afforded 5b. Treatment of 3,5‐bis(methylthio)‐1,2,4‐triazine (1d) with methyl iodide was found to give a mixture of N1 and N2 methiodides 2d and 3d which gave on hydrolysis 4b and 8b, respectively. Methylation of 6‐methyl derivatives 1c‐g gave analogous results, however the proportions of N1 methylated products were lower and the reaction rates higher in comparison to their respective lower homologues 1a,c,d. The structures of the mesoionic dimethyl derivatives were assigned from uv, ir, 1H nmr and electron impact mass spectra. The structural assignments were eventually confirmed by quantum chemical calculations of net charge distributions, bond lengths and ipso angles of the C5O bonds.
Synthesis of representative 10‐aryl‐, 10‐aralkyl‐ and 10‐heteraryl‐9H‐naphtho[1′,2′:4,5]thiazolo[3,2‐b]‐ [1,2,4]triazin‐9‐ones as potential anti‐HIV agents
Authors: Liu Kang‐Chien , Shih Bi‐Jane , Lee Chuen‐Hsiang
Published: March 2009

To prepare the title compounds, cyclocondensation of 1‐amino‐2‐iminonaphtho[1,2‐d]thiazole (2) with some representative glyoxylic acid derivatives was investigated. Heating 2 with methyl phenylglyoxylate (3a) in methanol afforded only the open chain intermediates 4a,b. However, when this reaction was performed in re‐fluxing glacial acetic acid, the expected compound, 10‐phenyl‐9H‐naphtho[1′,2′:4,5]thiazolo[3,2‐b][1,2,4]‐ triazin‐9‐one (5a) was produced in 27% yield. Similar treatment of 2 with benzyl‐, 2‐furyl‐ and 2‐thienylgly‐oxylic acids 3b‐d gave the corresponding 10‐benzyl‐, 10‐(2‐furyl)‐ and 10‐(2‐thienyl)‐9H‐naphtho[1′,2′:4,5]thi‐azolo[3,2‐b][1,2,4]triazin‐9‐ones 5b‐d in 48–67% yields. As by‐products, 9‐benzoyl‐ and 9‐(2‐thenoyl)naphtho‐[1′,2′:4,5]thiazolo[3,2‐b][1,2,4]triazoles 6a,d were also isolated. Compound 5a was selected for in vitro anti‐HIV evaluation but found to be inactive.
Synthesis of a new series ofN‐substituted‐3‐[l‐alkyl(aryl)‐ 4‐piperidyl]azetidin‐2‐ones as possible muscarinic agents
Authors: Cignarella Giorgio , Villa Stefania , Barlocco Daniela
Published: March 2009

A new series ofN‐substituted‐3‐[1‐alkyl(aryl)‐4‐piperidyl]azetidin‐2‐ones2a‐jstructurally related to the previously reported 2,7‐diazaspiro[3.5]nonan‐1‐ones1have been synthesized and tested for their activity as muscarinic agents, bothin vitroandin vivo. Preliminary pharmacological results showed that compounds2are devoid of significant cholinergic properties.
Conversion of 4‐amino‐4H‐1,2,4‐triazole to 1,3‐bis(1H‐azol‐l‐yl)‐2‐aryl‐2‐propanols and 1‐phenacyl‐4‐[(benzoyl or 4‐toluenesulfonyl)‐imino]‐(1H‐1,2,4‐triazolium) Ylides
Authors: Narayanan Anjana , Chapman David R. , Upadhyaya Subhash P. , Bauer Ludwig
Published: March 2009

A series of 1,3‐bis(1H‐azol‐1‐yl)‐2‐aryl‐2‐propanols17were synthesized in an one‐pot procedure by reacting l‐aryl‐2‐(1H‐1,2,4‐triazol‐l‐yl)‐ or l‐aryl‐2‐(1H‐imidazol‐l‐yl)ethanones with dimethylsulfoxonium methide in the presence of either 1,2,4‐triazole or imidazole. The aromatic groups in17were either 4‐bromo‐, 4‐chloro‐, 2,4‐dichloro‐ or 2,4‐difluorophenyl. 4‐Amino‐4H‐1,2,4‐triazole was acylated with either benzoyl or 4‐toluene‐sulfonyl chloride to afford [4‐(benzoyl or 4‐toluenesulfonyl)amino]4H‐1,2,4‐triazole. Subsequent alkylations with 4‐bromo‐ or 4‐chlorophenacyl bromide produced 1‐(4‐bromo‐ or 4‐chlorophenacyl)‐4‐[(benzoyl‐ or 4‐toluenesulfonyl)amino]‐1H‐1,2,4‐triazolium bromides. Neutralizations of these salts provided the corresponding ylides.
Nitrogen bridgehead compounds. Part 85. Synthesis and reactivity of 3,4‐dihydro‐1H,6H[1,4]oxazino[3,4‐b]quinazolin‐6‐ones
Authors: Hermecz István , Szilágyi Ildikó , Orfi László , Kökösi József , Szász György
Published: March 2009

3,4‐Dihydro‐1H,6H‐[1,4]oxazino[3,4‐b]quinazolin‐6‐one 3 and its 1‐methyl and 1‐hydroxy derivatives 8 and 13 were prepared by different routes. The active methylene group of compound 3 was reacted with electro‐hilic reagents (bromine, phenyldiazonium chloride, nitrous acid, a Vielsmeier‐Haack reagent, aromatic aldehydes and diethyl oxalate) to yield 1‐substituted‐3,4‐dihydro[1H,6H)‐1,4‐oxazino[3,4‐b]quinazo‐lin‐6‐ones. The reactivity of 1‐hydroxy and 1‐bromo derivatives 13 and 15 were also investigated in some reactions. The 3,4‐dihydro‐lH,6H‐[1,4]oxazino[3,4‐b]quinazolin‐6‐ones were characterized by means of uv, 1H and 13C nmr spectroscopy.
Stereoselective synthesis of 3‐azido‐2,3‐dideoxy‐D‐ribose derivatives and its utilization for the synthesis of anti‐HIV nucleosides
Authors: Jeong Lak S. , Beach J. Warren , Chu Chung K.
Published: March 2009

Detail account of the synthesis of 3′‐azido nucleosides utilizing 3‐azido‐2,3‐dideoxy‐D‐ribose derivative 7 as the key intermediate was described. The key intermediate 7 was synthesized from D‐mannitol in 8 steps in a preparative scale. The Michael reaction of the azide group with α,β‐unsaturated‐γ‐butyrolactone 4 was affected by the steric bulkiness of the substituent at the 5‐O position. A bulky t‐butyldiphenylsilyl substitution at 5‐O gave almost exclusively the α‐azido adduct 5b, while unsubstitution at 5‐O produced 1:1 mixture of α‐and β‐adducts. The ratio of α to β anomers in the condensation between azido acetate 7a and pyrimidine bases for the preparation of AZT and AZDU was greatly influenced by the solvent and the Lewis acid catalyst used. In the synthesis of 12 (AZDU, CS‐87), the combination of dichloroethane and trimethylsilyl triflate gave an optimal result, while in the case of 14 (AZT), various conditions gave similar ratio of α,β anomers. The azido intermediate 7b was also utilized for the synthesis of several 3′‐azido purine‐like nucleosides 16–27. The glycosylation was also affected by the Lewis acid catalyst. Boron trifluoride etherate gave the desired N1‐glycosylated compounds in which the α‐anomer was major, but other catalysts such as trimethylsilyl triflate or stannic chloride produced N2‐glycosylated compounds as the major products. The newly synthesized purine‐like compounds have been tested against HIV, however, none of them showed any significant activity.
An influence of a basic side chain moiety on the tautomer ratio between the enamine and methylene imine forms in azole condensed quinoxalines
Authors: Kurasawa Yoshihisa , Matsumoto Yuko , Ishikura Aiko , Ikeda Kazue , Hosaka Tomoyoshi , Takada Atsushi , Kim Ho Sik , Okamoto Yoshihisa
Published: March 2009

The reaction of 7‐chloro‐4‐(2‐cyano‐2‐hydroxyvinyl)tetrazolo[1,5‐α]quinoxaline 2a with 4‐aminopyridine, p‐toluidine or p‐aminophenol gave 7‐chloro‐4‐(4‐pyridylcarbamoylmethylene)‐4,5‐dihydrotetrazolo[1,5‐α]‐quinoxaline 7a, 7‐chloro‐4‐(p‐tolylcarbamoylmethylene)4, 5‐dihydrotetrazolo[1,5‐α]quinoxaline 8a or 7‐chloro‐4‐(p‐hydroxyphenylcarbamoylmethylene)‐4,5‐dihydrotetrazolo[1,5‐α]quinoxaline 9a, respectively. The reaction of 7‐chloro‐4‐(2‐cyano‐2‐hydroxyvinyl)‐1,2,4‐triazolo[4,3‐α]quinoxaline 2b with 4‐aminopyridine, p‐toluidine or p‐aminophenol afforded 7‐chloro4‐(4‐pyridylcarbamoylmethylene)‐4,5‐dihydro‐1,2,4‐triazolo‐[4,3‐α]quinoxaline 7b, 7‐chloro‐4‐(p‐tolylcarbamoylmethylene)‐4,5‐dihydro‐1,2,4‐triazolo[4,3‐α]quinoxaline 8b or 7‐chloro‐4‐(p‐hydroxyphenylcarbamoylmethylene)‐4,5‐dihydro‐1,2,4‐triazolo[4,3‐α]quinoxaline 9b, respectively. The reaction of compound 2a with 2‐aminopyridine or 3‐aminopyridine provided 7‐chloro‐4‐(2‐pyridyl‐carbamoylmethylene)‐4,5‐dihydrotetrazolo[1,5‐α]quinoxaline 10 or 7‐chloro‐4‐(3‐pyridyl‐carbamoylmethylene)‐4,5‐dihydrotetrazolo[1,5‐α]quinoxaline 11, respectively. Compounds 7a,b(4‐pyridylcarbamoyl) predominated as the enamine tautomer A in a trifluoroacetic acid solution, while compounds 8a,b (p‐tolylcarbamoyl) and compounds 9a,b (p‐hydroxyphenylcarbamoyl) coexisted as the enamine A and methylene imine B tautomers in a trifluoroacetic acid solution. Moreover, the ratio of the enamine tautomer A elevated in an order of compound 11 (3‐pyridylcarbamoyl), compound 10 (2‐pyridylcarbamoyl) and compound 7a (4‐pyridylcarbamoyl), reflecting an order of the increase in the pKa values of the aminopyridine side chain moieties. In general, the ratio of the enamine tautomer A was higher in the basic carbamoyl derivatives 7–11 than in the neutral ester derivatives 3a,b. From these results, the basic side chain moiety of the tetrazolo[1,5‐α]quinoxalines 7a‐11 or 1,2,4‐triazolo[4,3‐α]quinoxalines 7b‐9b was found to increase the ratio of the enamine tautomer A in trifluoroacetic acid media.
Synthesis of 2H‐pyrano[2,3‐b]quinolines. Part I
Authors: Cziáky Zoltán , Sebők Péter
Published: March 2009

3,4‐Dihydro‐2H‐pyrano[2,3‐b]quinolines 5a‐e and 2H‐pyrano[2,3‐b]quinolines 10a‐c were synthesised starting from the appropriate ω‐chloro‐n‐valeroylanilides 2a‐e. Compounds 10a‐c were transformed to analogs of the novel antihypertensive agent Cromakalim (1).
Some nitro derivatives of 1,4‐benzodioxino[2,3‐b]pyridine. Crystal and molecular structure of 2,7,8‐trinitro‐1,4‐benzodioxino[2,3‐b]pyridine
Authors: Piórko Adam , Christie Sean , Crook Michelle , Sampson Peter
Published: March 2009

The electrophilic nitration of 1,4‐benzodioxino[2,3‐b]pyridine 1 with nitric acid in sulfuric acid has been studied. Some of the products of nitration including 7‐ and 8‐nitro derivatives 2a and 2b, respectively, 7,9‐, 7,8‐ and 6,8‐dinitro derivatives 3a, 3b and 3c, respectively, and 2,7,8‐trinitro derivative 4 have been isolated and characterized. The structure of isomers have been assigned for derivatives 3b and 4 while tentative structures have been proposed for the other products. The cyclopentadienyliron complex of 1 gives the same reaction products under similar conditions while for some other milder nitrating reagents no reaction was observed. 2,7,8‐Trinitro‐1,4‐benzodioxino[2,3‐b]pyridine 4 crystallizes in the monoclinic system, space group P21/c; the dihedral angle between the planes of outer rings was found to be 174.65(8) degrees. The planes of the nitro groups have been found to be rotated with respect to the appropriate pyri‐dine and benzene ring planes by 11.13(11) degrees for the 2‐nitro group and 47.56(9) and 29.80(9) degrees for the 7‐nitro and 8‐nitro groups, respectively.
Studies on isocyanides and related compounds. An unusual synthesis of imidazolyloxazolones
Authors: Bossio Ricardo , Marcaccini Stefano , Pepino Roberto , Paoli Paola
Published: March 2009

The reaction between ethyl (Z)‐3‐dimethylamino‐2‐isocyanoacrylate (1) and arenesulfenyl chlorides 6a‐c afforded the unexpected imidazolyloxazolones 7a‐c. The structure of compounds 7a‐c was in agreement with their 1H nmr, ir and ms data and was confirmed by X‐ray analysis of 7a.
On triazoles. XXXIV. The correct structure of the ethoxycarboxylated 5‐amino‐1H‐1,2,4‐triazole and its product with hydrazine
Authors: Reiter József
Published: March 2009

The structure of the ethoxycarboxylated product of 5‐amino‐1H‐1,2,4‐triazole and its hydrazide was corrected using their ir, pmr, cmr and mass spectra.
Annulation reactions of 3‐aminoisoquinolin‐l(2H)‐one. Synthesis of pyrimido[1,2‐b]isoquinolines, pyrido‐[2,3‐c]isoquinolines and pyrrolo[2,3‐c]isoquinolines
Authors: Deady Leslie W. , Quazi Nurul H.
Published: March 2009

Reactions of the title compound with the malonic acid derivatives diethyl ethoxymethylenemalonate (EMME), ethyl ethoxymethylenecyanoacetate (EMCA) and ethoxymethylenemalononitrile (EMMN) are reported. Condensations occur at the amino group or C‐4, depending on conditions and the former intermediate was successfully cyclized to the pyrimido[1,2‐b]isoquinoline system. Reactions with 2,4‐pentanedione and p‐bromophenacyl bromide gave only the angular systems, pyrido[2,3‐c]isoquinoline and pyrrolo[2,3‐c]isoquin‐oline, respectively.
Synthesis of unsymmetrically substituted 4H‐1,2,4‐triazoles
Authors: Carlsen Per H. J. , Jørgensen Kåre B.
Published: March 2009

A general method was developed for the synthesis of unsymmetrically 3,5‐disubstituted 4H‐1,2,4‐tria‐zoles (Ph, H or Ph, CH3) with allyl or benzyl groups in the 4‐ring position. The reaction of the corresponding 3,5‐disubstituted 1,3,4‐oxadiazoles with allylamine or benzylamine gave the desired compounds. The oxadiazoles were prepared by heating at 100° N,N'‐diacylhydrazines with phosphorus pentoxide.
Mono‐, and dibenzacridine imines. Synthesis of 1a,11b‐ dihydrobenz[c]azirino[α]acridine, 4b,5a‐dihydrodibenz[c,h]‐ azirino[α]acridine and 1a,13b‐dihydrodibenz[c,j]azirino[α]acridine
Authors: Bazanov Nina , Dayan Yael , Blum Jochanan , Harvey Ronald G.
Published: March 2009

The syntheses of the K‐imine derivatives of benz[c]acridine, dibenz[c,h]acridine and dibenz[a,h]acridine are described. The parent hydrocarbons 1, 6 and 11 were oxidized with sodium hypochlorite under phase transfer conditions to the corresponding K‐oxides 4,9 and 14, which in turn were reacted with sodium azide. The resulting azido alcohols were then cyclized with tributylphosphine to the title compounds 5,10 and 15.
Synthetic exploitation of the ring‐opening of 3,4‐dinitrothiophene. Part 4. Synthesis of 1,4‐disubstituted 3‐hydroximino‐2‐nitro‐1‐butenes and their cyclization to 4‐nitroisoxazoles
Authors: Dell'Erba Carlo , Novi Marino , Petrillo Giovanni , Stagnaro Paola
Published: March 2009

The reduction of a single nitrovinyl moiety in 1,4‐dialkyl‐ and 1,4‐diaryl‐2,3‐dinitro‐1,3‐butadienes 1 with stannous chloride dihydrate in ethyl acetate furnishes the corresponding 3‐hydroximino‐2‐nitro‐l‐butenes 4 in satisfactory yields. The oxidative cyclization of the latter compounds gives variable yields of 3,5‐disubsti‐tuted 4‐nitroisoxazoles 5, most likely arising from aromatization of the corresponding 4,5‐dihydroisoxazoles, formed through an intramolecular Michael addition of the hydroximino group in 4 to the nitroalkene functionality. In the case of the l‐naphthyl derivative 4d such oxidative cyclization mainly leads to the competitive formation of 3‐[(l‐naphthyl)methyl]‐2‐nitrobenzo[f]quinoline N‐oxide 7.
Steric interactions in 2‐substituted imidazoles. The molecular structure of 1‐methyl‐2‐phenylimidazole and 1‐methyl‐4‐phenylimidazole
Authors: Hallows Wendy A. , Carpenter Gene B. , Pevear Karen A. , Sweigart D. A.
Published: March 2009

The crystal and molecular structures are reported for two isomeric imidazoles: 1‐methyl‐2‐phenylimida‐zole (1) and 1‐methyl‐4‐phenylimidazole (2). In molecule 2 the phenyl ring is rotated by 7.3° from the het‐erocyclic plane due to steric interactions. The steric congestion is much more severe in 1, with the adjacent methyl and phenyl substituents mininizing nonbonded interactions via a 32.3° rotation of the phenyl ring and a 0.159 Å displacement of the methyl carbon from the heterocyclic plane.
A study of the photochemically induced electron‐transfer reactions between pyridinedicarbonitriles and primary and secondary aliphatic amines
Authors: Bernardi Rosanna , Caronna Tullio , Poggi Gabriella , Vittimberga Bruno M.
Published: March 2009

A study on the photochemically induced electron‐transfer from primary and secondary aliphatic amines as donors to pyridinedicarbonitriles as the acceptor is reported. A comparison between the substitution positions and the spin density distributions, obtained via theoretical calculations using the 6‐31+G basis set, shows some discrepancies, and forms the basis of a hypothesis on the mechanism of the reaction.
Mannich reactions of carbonyl compounds and enamines with benzotriazole as the NH component
Authors: Katritzky Alan R. , Galuszka Barbara , Rachwal Stanislaw , Black Michael
Published: March 2009

Boron trifluoride catalyses reactions of 1‐(hydroxymethyl)benzotriazole with ketones to give predominantly monosubstituted Mannich products. In unsymmetrical ketones, a methylene is slightly more reactive than a methyl group. For 1,3‐diketones and diethyl malonate, substitution occurs on the central methylene group. β‐Aminocrotononitrile and β‐aminocrotonate undergo Mannich condensations with benzotri‐azole and formaldehyde without any catalyst. Preliminary investigations of the reactivity of the Mannich bases thus obtained are reported.
Cyclazines and topological resonance energies
Authors: Kurihara Teruo , Kerim Ablikim , Ohta Akihiro
Published: March 2009

The resonance energies and magnetic properties of cyclazines such as pyrido[2,1,6‐cd]quinolizine (1) and pyrido[2,1,5‐de]quinolizine (6) were calculated by means of Aihara's TRE. Consequently, cycl[3.2.2]azines and cycl[3.3.3]azines were predicted to be aromatic, while cycl[4.3.2]azines were predicted to be anti‐aromatic.
Oxidative halogenation of substituted pyrroles with Cu(II). Part IV. Bromination of 2‐(2′‐hydroxybenzoyl)pyrrole. A new synthesis of bioactive analogs of monodeoxypyoluteorin
Authors: Petruso Salvatore , Bonanno Silvana , Caronna Sergio , Ciofalo Maurizio , Maggio Benedetta , Schillaci Domenico
Published: March 2009

The selective bromination with copper(II) bromide of the pyrrole ring in 2‐(2′‐hydroxybenzoyl)pyrrole II in the heterogeneous phase is described giving in almost quantitative yield the 4,5‐dibromo derivative VI. The subsequent introduction of halogen into the phenol moiety was observed when the reaction was performed in the homogeneous phase with an excess of halogenating agent. The pentabromo derivative IX, a compound very active against Staphylococcus aureus (mic = 17 nmoles per dm−3), was obtained by exhaustive bromination of the title compound. Poor yields of chloro derivatives of II were obtained by reaction of the parent compound with copper(II) chloride.
Synthesis of p‐aminobenzamides of aminopiperidazines as potential antiarrhythmic agents
Authors: Kornet M. J. , Ali K. Abdul‐Nabi , Steinberg Mitchell I.
Published: March 2009

1,2‐Dimethyl‐4‐aminopiperidazine (4), 1‐(2‐aminoethyl)2‐methylpiperidazine (11), 2‐(2‐aminoethyl)‐3‐meth‐yl‐2,3‐diazabicyclo[2.2.1]heptane (16), and 1,2‐dimethyl‐3‐aminomethylpiperidazine (21) have been synthesized. Amines 4, 11, and 16 were converted to the corresponding p‐nitrobenzamides 7,12, and 17. Catalytic reduction of the latter nitro derivatives gave the corresponding p‐aminobenzamides 8,13, and 18. For comparative studies, the acyclic analog, 4‐amino‐N[2‐(1,1,2‐trimethylhydrazino)ethyl]benzamide (25) was also synthesized. Compounds 8,13 and 25 which are analogs of procainamide were evaluated in the isolated cardiac Purkinje fiber preparation by measuring their effects on the action potential upstroke velocity.
A possible pathway for the reaction of triethyl (1‐methylindol‐2‐yl)borate with cationic electrophiles in the presence of cuprous cyanide
Authors: Ishikura Minoru , Terashima Masanao
Published: March 2009

On the preferential formation of 3‐substituted indoles from triethyl (1‐methylindol‐2‐yl)borate in the presence of cuprous cyanide and cationic electrophiles, it was supposed that the reaction seems to proceed through a transposition path from boron to copper.
Carbazole synthesis via an in situ trapping strategy with indolyl enol ethers
Authors: Pindur Ulf , Rogge Martina , Rehn Carsten , Massa Werner , Peschel Beate
Published: March 2009

Indolyl enol ethers, generated from the alkoxy(indolyl)carbenium tetrafluoroborates 1 by treatment with sodium hydride, can be trapped with dimethyl acetylenedicarboxylate or N‐phenylmaleimide to furnish the selectively functionalized carbazoles 3,4,5,9,10, and 13. In addition, the biaryl derivatives 6 and 11 are produced by a ring‐opening reaction of the primarily formed Diels‐Alder adduct. In the case of the biaryl derivative 6, an X‐ray crystal structure analysis yields valuable information on constitutions and configurations in the biaryl series. The phenomenon of atropisomerism is discussed for this compound.
On triazoles. XXXIII. The reaction of potassium triazolyldithiocarbonates with dihaloalkanes
Authors: Pongó LÁSzló , Sohár PÁL , Reiter JÓZsef , Dvortsák Péter , Bujtás György
Published: March 2009

The reaction of potassium (5‐amino‐3‐Q‐1,2,4‐triazolyl)dithiocarbonates 2 with 1,ω‐dihaloalkanes 7‐10 to yield ω‐haloalkyldithiocarbonates 11‐12, ω‐alkylene‐bis(dithiocarbonates) 13‐15 and different by‐products as the corresponding 7,8‐dihydro[1,2,4]triazolo[1,5‐c][1,3,5]thiadiazepine‐5(9H)‐thione (16), 7,8,9,10‐tetrahy‐dro[1,2,4]triazolo[1,5‐c][1,3,5]thiadiazocine‐5‐thione (17) and 1,7‐dihydro‐5H‐1,2,4‐triazolo[1,5‐c][1,3,5]thiadi‐azine‐5‐thione (22) derivatives all three representing novel ring systems were obtained. Repeating the reactions with dipotassium salts 3 the corresponding iminodithietans 18, imino‐1,3‐dithiolanes 19 and imino‐1,3‐dithianes 20 were obtained. Unexpectively, the imino‐1,3‐dithiolanes (19) rearranged to the corresponding thiazolidines 24‐27 under rather mild conditions. A possible mechanism is proposed for this rearrangement.
Furo[3,2‐e]pyrrolo[1,2‐α][1,4]diazepine and derivatives
Authors: Chédru Christophe , Decroix Bernard , Morel Jean , Povazanec Frantisek
Published: March 2009

The 5,10‐dihydro‐4H‐furo[3,2‐e]pyrrolo[1,2‐α][1,4]diazepin‐5‐one (7) and furo[3,2‐e]pyrrolo[1,2‐α][1,4]diaze‐pine (10) are synthesized from suitable isocyanates 3a,b in acetic acid. The reactivity of 10 (C‐ and N‐alkyla‐tion) is investigated.
Syntheses of substituted 2‐(1‐methyl‐5‐nitro‐2‐benzimidazolyl)quinolines
Authors: Alimohammadi F. , Abedifard S. , Shafiee A.
Published: March 2009

Reaction of N‐methyl‐2‐amino‐4‐nitroaniline (1) with lactic acid afforded 2‐(1‐hydroxyethyl)‐1‐methyl‐5‐nitrobenzimidazole (2). Oxidation of compound 2 with chromic acid in acetic acid gave 2‐acetyl‐1‐methyl‐5‐nitrobenzimidazole (3). Reaction of compound 3 with substituted 2‐aminobenzaldehyde (4) under basic conditions yielded substituted 2‐(1‐methyl‐5‐nitro‐2‐benzimidazolyl)quinolines (5). Condensation and cyclization of o‐aminoacetophenone (or substituted o‐aminobenzophenones) with compound 3 under acetic condition afforded compound 7. Condensation and cyclization of compound 1 with indole‐3‐carboxaldehyde (11) in ethanol in the presence of excess nitrobenzene gave 3‐(1‐methyl‐5‐nitro‐2‐benzimidazolyl)indole (12).
Reactions on the dimethylphenylbenzacridinones. VI. Hydrogenation of ortho‐nitrophenyl derivatives
Authors: Martínez Roberto , Eduardo Cortée C. , Olivia Salazar E. , Irma Linzaga E.
Published: March 2009

Catalytic hydrogenation of o‐nitrophenylbenz[a], benz[c], dibenz[a,h] and dibenz[a,g]acridinones using Pd/C as catalyst, at 60 psi of pressure, gave the hiterto unknown benzoquinoacridine N‐oxides and benzo‐pyranonaphthyridine N‐oxides. The structure of all products was corroborated by ir, 1H‐ and 13C‐nmr and mass spectra data.
New symmetric and unsymmetric polyfunctionalized 2,2′‐bipyridines
Authors: De Vains J. B. Regnouf , Papet A. L. , Marsura A.
Published: March 2009

Recently, a large number of biheterocycles have been synthesized in order to build macrobicyclic cryp‐tates. To pursue investigations in this field, we prepared new symmetric and unsymmetric functionalized bi‐pyridines and we describe here two synthetic strategies leading to new tetrasubstituted 3 to 15 and trisubsti‐tuted 17 to 29 bipyridines. Modification at the α,α'‐methyl groups and introduction of functionalities in the 4,4′‐positions have been performed after N‐O activation of the starting 6,6′‐dimethyl‐2,2′‐bipyridine unit. In the case of cyano and hydroxymethyl groups, alkylation of the N‐O function followed by a nucleophilic attack with the CN anion or an hydroxymethyl radical allowed us to obtain the dissymmetric species. To understand observed differencies between cyanation and hydroxymethylation processes, the unstable and hygroscopic N‐methoxybipyridinium salt 30 has been isolated and characterized by nmr. Dibromomethyl compounds 8, 15, 29 were finally obtained in good to moderate yields by the Boekelheide rearrangement followed by a pseudohalogen exchange.
Reaction of 2‐trifluoromethyl‐4H‐3,1‐benzoxazin‐4‐one derivatives with carboethoxymethylenetriphenylphosphorane
Authors: Murphy Steven M. , Stanforth Stephen P.
Published: March 2009

Treatment of a series of 2‐trifluoromethyl‐4H‐3,1‐benzoxazin‐4‐one derivatives 1 with carboethoxymethyl‐enetriphenylphosphorane 2 yielded the phosphoranes 3 in boiling toluene solution. Thermolysis of these phosphoranes 3 gave esters 6.
Reactivity of 3,3′‐methylenebis(5‐phenyl)oxazolidine with urea, thiourea and cyanamide. An alternative mechanism for the α‐ureidoalkylation of 2‐amino‐l‐phenylethanol
Authors: Pevarello Paolo , Pinciroli Vittorio , Varasi Mario
Published: March 2009

The title compound 1 reacts with urea, thiourea and cyanamide, yielding the corresponding 1,3,5‐triazine‐2‐one 3a, ‐2‐thione 3b and an N,N‐dicyanobisaminal 4 derivative, respectively. An alternative mechanism for this class of α‐ureidoaikylations is proposed.
Dichloromethylenation of substituted 1H‐isoindole‐1,3‐(2H)‐diones (phthalimides)
Authors: Robinson Denise , Stanley Alan L. , Stanforth Stephen P.
Published: March 2009

A number of substituted 1H‐isoindole‐1,3‐(2H)‐dione derivatives (phthalimides) underwent dichloro‐methylenation when reacted with a mixture of triphenylphosphine and carbon tetrachloride.
Reaction of tetrahydrobenz[a]acridinones with hydroxylamine hydrochloride. VII
Authors: Martínez Roberto , Rubio Manuel F. , Guillermo Ramírez G. , Camacho Tomas , Irma Linzaga E. , Mancera Claudia
Published: March 2009

Oximation of ortho‐substituted phenylbenz[a]acridinones using hydroxylamine hydrochloride, sodium hydroxide and ethanol as the solvent gave always the benzoquinacridine N‐oxide 2. Oximation of para‐substituted phenylbenz[a]acridinones, however, gave only the corresponding oximes. The structure of all products was corroborated by ir, 1H and 13C‐nmr and mass spectral data. Theoretical calculations support the experimental findings.
Abnormal ring closure and oxidation in situ of 2‐hydroxy‐5‐nitrobenzaldehyde in the hantzsch synthesis
Authors: Menconi Italo , Angeles E. , Martínez Luisa , Posada Maria E. , Toscano Rubén A. , Martínez Roberto
Published: March 2009

The Hantzsch condensation of 2‐hydroxy‐5‐nitrobenzaldehyde, ethyl acetoacetate and ammonia gave the hitherto unknown 2‐methyl‐3‐ethoxycarbonyl‐4‐ethoxycarbonylmethyl‐6‐(2‐hydroxy‐5‐nitrophenyl)‐pyridine via an unusual condensation and oxidation in situ.
Preparation of 3‐hydroxyisoindolin‐1‐ones and o‐acylbenzamides. A study of ring‐chain tautomerism
Authors: Nishio Takehiko , Yamamoto Hiroshi
Published: March 2009

3‐Hydroxyisoindolinones (ring form) as well as their chain tautomers, o‐acylbenzamides, were prepared from the reactions of 3‐benzalphthalide 1, 3‐halophthalides 3, and o‐acylbenzoic acids 6 or their esters 7 with amines 2, and those of phthalimides 4 with Grignard reagents 5. The characteristic spectroscopic properties of ring and chain forms are observed in the ir and 13C‐nmr spectra. The significance of the spectroscopic results is discussed, as is the relationship between the structure of the products and the position of the ring‐chain equilibrium.
A new route to the asymmetric cylindrical macrotricyclic ligands
Authors: Krakowiak Krzysztof E. , Bradshaw Jerald S. , Kou Xiaolan , Dalley N. Kent
Published: March 2009

New asymmeric cylindrical macrotricyclic ligands have been prepared containing two diaza‐12‐crown‐4 units connected by diethyleneoxy or triethyleneoxy and meta‐ or para‐xylylene bridges, 2‐4. These materials were prepared in three steps by first treating 6‐tosyl‐6‐aza‐3,9‐dioxa‐1,11‐undecanediyl ditosylate with 3‐oxa‐1,5‐pentanediamine or 3,6‐dioxa‐1,8‐octanediamine to form ditosyl‐substituted bis(diaza‐12‐crown‐4)s connected by a diethyleneoxy or triethylencoxy bridge. These latter compounds were detosylated and treated with either para‐ or meta‐α,α'‐dibromoxylene to give new asymmetric cylindrical macrotricycles 2‐4. The solid state structure of one of these ligands, 3, has been determined by X‐ray diffraction methods.
Reaction of amino substituted heterocycles with one heteroatom in a five‐membered ring as enamines. A revision
Authors: Almerico A. M. , Cirrincione G. , Diana P. , Grimaudo S. , Dattolo G. , Aiello E. , Mingoia F.
Published: March 2009

2‐Aminoheterocycles (pyrrole, furan, and thiophene) exist in solution in the amino form of type 1 and 5. They undergo protonation at the exocyclic nitrogen in DMSO/TFA and protonation at position 5 in TFA. However when the electrophile is different from proton the 2‐aminoheterocyles do not react as enamines (C‐acylation is never observed), but their behavior is typical of aromatic amines, giving rise to N‐acylated product of type 9.
Retro‐ene reaction. II. Reaction of 4,5‐dichloro‐1‐hydroxy‐methylpyridazin‐6‐one with alkyl halides and carboxylic acid chlorides
Authors: Kim Sung‐Kyu , Cho Su‐Dong , Kweon Deok‐Heon , Lee Sang‐Gyeong , Chung Joo‐Wha , Shin Sung Chul , Yoon Yong‐Jin
Published: March 2009

1‐Alkyl‐4,5‐dichloropyridazin‐6‐oncs and (4,5‐dichloro‐6‐oxopyridazin‐1‐yl)methylcarboxylates were synthesized from 4,5‐dichloro‐1‐hydroxymethylpyridazin‐6‐one and the corresponding alkyl halides or carboxylic acid chlorides. Also the reaction mechanisms via a fragmentation of retro‐ene type are discussed.
Synthesis of phenylpyrrolylpyrroles. Part II
Authors: Dumoulin H. , Rault S. , Robba M.
Published: March 2009

A series of methyl or ethyl 3‐(N‐arylpyrrol‐3‐yl)‐1H‐pyrrole‐2‐carboxylates and 2,4‐dicarboxylates have been synthesized using an alkyl isocyanides addition‐cyclization with N‐arylpyrrole derivatives such as the carboxaldehydes and nitropropenes.
Synthesis of substituted azaoxindoles for the preparation of aza‐tenidap analogs
Authors: Robinson Ralph R. , Donahue Kathleen M. , Son Paul S. , Wagy Steven D.
Published: March 2009

The preparation of a set of eight azaoxindoles bearing substituents on the aromatic nucleus is outlined. These compounds were required for the preparation of aza‐analogs of the anti‐inflammatory oxindole tenidap. Two methods of synthesis were used, the first involving the addition of malonate to 2‐chloro‐3‐nitropyridine derivatives followed by nitro group reduction and one‐pot cyclization/hydrolysis/decarboxylation. The second method, utilizing the vicarious nucleophilic substitution (VNS) reaction of nitropyridine derivatives (followed by nitro group reduction and one‐pot cyclization/hydrolysis), constitutes a novel route to azaoxindoles.
Synthesis of condensed tricyclic pyrazolo[3,4‐b]thieno[2,3‐d]pyridine and related isostere derivatives
Authors: De Carvalho Alcione S. , Fraga Carlos A. M. , Barreiro Eliezer J.
Published: March 2009

In this paper we report the synthesis of an isosteric series of new heterotricyclic derivatives, corresponding to pyrazolo[3,4‐b]thieno[2,3‐d]pyridine (1), pyrazolo[3,4‐b]furano[2,3‐d]pyridine (2) and pyrazolo[3,4‐b]pyrrolo[2,3‐d]pyridine (3). These functionalized compounds were obtained, in high overall yield, by an ‘one‐pot’ reaction of the chloroester intermediate 4, possessing the pyrazolo[3,4‐b]pyridine system, with an adequate α‐hetero‐acetyl ester derivative, in SNAr/Dieckman cyclization type consecutive reactions.
Synthesis of azolylalkylquinolines with cytotoxic activity
Authors: Abel Mark D. , Luu Hiep T. , Micetich Ronald G. , Nguyen Dai Q. , Oreski A. Bernadette , Tempest Mark L. , Daneshtalab Mohsen
Published: March 2009

The syntheses of various azolylalkylquinoline derivatives in which the nature of the linkage between the quinoline and azolylalkyl moieties of the molecule were altered are described. The compounds were tested for cytotoxic activity towards cancer cells and compound 27 was found to exhibit moderate in vivo activity in a murine sarcoma model.
Synthesis and stereochemistry of oxazolo[4′,5′:1,2]benz[5,4,3‐c, d]‐indole derivatives as intermediates on the way to a selective dopamine autoreceptor agonist
Authors: Gmeiner Peter , Bollinger Bernd , Lotter Hermann
Published: March 2009

An expedient and practical variant of the synthesis of the selective dopamine autoreceptor agonist 5 from the benzindolone 1 is described. The reaction sequence includes a two‐fold epimerization at the α‐position of the lactam function. The structure of the intermediate 9a was confirmed by X‐ray structure analysis.
Synthesis and Complexation Properties of Pyrimidine‐Derived Crown Ether Ligands
Authors: Redd J. T. Y. , Bradshaw Jerald S. , Huszthy Peter , Izatt Reed M. , Dalley N. Kent
Published: March 2009

Five new proton‐ionizable macrocyclic ligands containing a pyrimidone‐subcyclic unit, 6–10, were prepared from the previously prepared pyrimidinocrown ethers 1–5 (see Figure 1 and Scheme 1). One of the new proton‐ionizable crown ethers is chiral. The proton‐ionizable pyrimidonocrown ethers were prepared in high yields by treating the appropriate methoxy‐substituted pyrimidinocrown with 5 M sodium hydroxide in a 50% alcohol‐water mixture. Complexation properties of four of the pyrimidine‐derived macrocycles were studied by various nmr techniques. Pyrimidono‐18‐crown‐6 (9) forms a strong complex with benzylammonium perchlorate and also forms a complex with benzylamine. (S, S)‐Dimethyl‐substituted pyrimidino‐ and pyrimidono‐18‐crown‐6 ligands 4 and 9 form stronger complexes with the (R)‐form of α‐(1‐naphthyl)ethylammonium perchlorate than with the (S)‐form. (S, S)‐Dimethyl‐substituted pyrimidono‐18‐crown‐6 (9) also forms a stronger complex with (R)‐α‐(1‐naphthyl)ethylamine than with the (S)‐form. The crystal structure for compound 7 is reported.
Synthesis of 2,3‐dihydro‐3‐hydroxy‐2‐(pyrrol‐1‐ylmethyl)‐1H‐isoindol‐1‐one. An intermediate for the synthesis of tetracyclic systems
Authors: Korenova Anna , Netchitailo Pierre , Decroix Bernard
Published: March 2009

N‐Chloromethylphthalimide 1 and the potassium salt of pyrrole gave N‐(pyrrol‐1‐ylmethyl)pbthalimide 2. Reduction of 2 led to the hydroxyisoindolone 3. This hydroxylactam cyclized under acidic conditions to lead to a pyrroloimidazoloisoindolone 4 via an acyliminium ion. Transformation of 3 with acetic acid derivatives provided 5, 7 and 9 which gave by intramolecular cyclization, tetracyclic compounds 6, 10 and 11.
Synthesis of 4‐(pyrazol‐5‐yl)‐1,2,4‐triazole‐3‐thiones
Authors: Vicentini Chiara B. , Manfrini Maurizio , Veronese Augusto C. , Guarneri Mario
Published: March 2009

Condensation of pyrazolyl isothiocyanates 2 with N‐substituted hydrazines provided the 2‐methyl/phenyl‐4‐(pyrazol‐5‐yl)thiosemicarbazides 3. Cyclization of 3 with formic acid‐acetic anhydride or with triethyl orthoacetate‐acetic anhydride provided 4‐(pyrazol‐5‐yl)‐l,2,4‐triazole‐3‐thiones 4a‐f and 5‐methyl‐4‐(pyrazol‐5‐yl)‐1,2,4‐triazole‐3‐thiones 4g‐I respectively.
A new preparation of substituted 4H‐1‐benzothiopyran‐4‐ones from c(α)N‐benzoylhydrazones or c(α)N‐carboalkoxyhydrazones and methyl thiosalicylate
Authors: French Kristen L. , Angel April J. , Williams Angela R. , Hurst Douglas R. , Beam Charles F.
Published: March 2009

C(α)N‐Benzoylhydrazones or C(α),N‐carboalkoxyhydrazones were dilithiated with excess lithium diisopropylamide, and the dianion‐type intermediates were condensed with lithiated methyl thiosalicylate, followed by cyclization/hydrolysis to substituted 4H‐1‐benzothiopyran‐4‐ones (thioflavones/thiochromones).
Synthesis of purinobenzothiazine and pyridothiazinopurine derivatives. Two new heterocyclic ring systems
Authors: Settimo Antonio Da , Marini Anna Maria , Primofiore Giampaolo , Settimo Federico Da , Bertini Daniele
Published: March 2009

The synthesis of derivatives of two new heterocyclic systems, purino[8,7‐b][1,3]benzothiazine and pyrido[3′,2′:5,6][1,3]thiazino[3,2‐f]purine, was effected by the Ullmann reaction between 8‐mercaptotheophylline or 8‐bromotheophylline with the appriopriately substituted benzoic or nicotinic acid, respectively. The 8,8′‐dithiobistheophylline is also reported.
Synthesis of aryl ω‐(1‐methyl‐5‐imidazolyl and 1H‐5‐tetrazolyl)alkyl ketones
Authors: Lee Jae Jeong , Huang Liang‐Fu , Zaw Kyaw , Bauer Ludwig
Published: March 2009

Successful syntheses of 2,4‐dichlorophenyl 2‐(1‐methyl‐5‐imidazolyl)ethyl and 2,4‐dichlorophenyl 3‐(1‐methyl‐5‐imidazolyl)propyl ketones are described. In addition, syntheses of 2,4‐dichlorophenyl and 4‐chlorophenyl 3‐(1‐methyl‐1H‐5‐tetrazolyl)propyl ketones are reported.
Formation and structure of 1‐Amino‐4‐methyl‐4‐(4‐methyl‐5‐phenyl‐1H‐pyrazol‐3‐ylamino)‐3‐phenyl‐4,5‐dihydro‐1H‐pyrazol‐5‐one
Authors: Donati Donato , Fusi Stefania , Ponticelli Fabio
Published: March 2009

The title compound 3 was obtained during the rearrangement of isoxazol‐5‐yl hydrazine 1 to 1‐aminopyrazolone 2 at 115°. X‐ray analysis of the corresponding benzylidene derivative allowed us to achieve the structure assignment.
Syntheses of 4 and 5‐alkylsulfonylimidazoles
Authors: Shafiee A. , Akbarzadeh T. , Foroumadi A. , Hadizadeh F.
Published: March 2009

A series of isomeric 4 and 5‐alkylsulfonyl, alkylsulfinylimidazoles 9,10 were prepared by two general methods. Chlorosulfonation of imidazole afforded 4(5)‐chlorosulfonylimidazoles 2, 4, 5. The chlorosulfonyl derivatives were reduced, alkylated and oxidized to give 9 and 10. In the second method 2, 4, 5 were converted to sodium sulfinate 8 and reacted with alkyl halides to afford the title compound 9.
Synthesis of 5‐dialkylaminothiocarbonylthiobarbituric acids and 5‐diethyiaminothiocarbonylthio‐6‐aminouracil
Authors: Neilands Ojars Y A. , Sudmale Ineta , Schnell Barbara , Georgieva Krassimira , Kappe Thomas
Published: March 2009

The title compounds are obtained by three different methods. The aminothiocarbonylthiolation of barbituric acids 1 and aminouracil (5) can be accomplished in one step by reaction with thiuram disulfides in the presence of potassium carbonate. On the other hand, compounds 4 can be obtained via the salt of chloro derivative 2 or the corresponding iodonium ylides 3. The aminouracil derivative 7 was obtained in a similar fashion from 5 directly or via iodonium betaine 6.
An efficient stereospecific preparation of (Z)‐3‐methylidene‐selenophthalides and (z)‐3‐methylidenetellurophthalides
Authors: Sashida Haruki , Kawamukai Atsusbi
Published: March 2009

(Z)‐3‐Methylideneselenophthalides 5A and (Z)‐3‐methylidenetellurophthalides 5B were easily prepared by the regioselective and stereoselective reaction of 2‐ethynylbenzoyl chlorides 3 with sodium hydroselenide and sodium hydrotelluride in good yields, respectively.
Synthesis of hexaazacryptands containing furan and benzene groups in the bridging arms
Authors: Krakowiak Krzysztof E. , Bordunov Andrei V. , Bradshaw Jerald S.
Published: March 2009

Two new hexaazacryptands were prepared. One contains two propylene groups and a 2,5‐furandimethylene unit between the nitrogen atoms of each bridge. The other has two propylene groups and a p‐phenylene unit between the nitrogen atoms of each bridge.
(E)‐1‐benzotriazolyl‐3‐(phenylsulphonyl)‐1‐propene and its alkylation reactions
Authors: Katritzky Alan R. , Nichols Daniel A. , Qi Ming
Published: March 2009

(E)‐1‐Benzotriazolyl‐3‐(phenylsulphonyl)‐1‐propene (6) has been synthesized and its alkylation was studied. The results showed that the phenylsulphonyl group is a more powerful α‐directing group than the benzotriazolyl group in the corresponding 1,3‐dihetero‐stabilized allyl anion.
Saturated heterocycles. 254. synthesis and stereochemistry of saturated or partially saturated pyridazino‐[6,1‐b]‐ and phthalazino[1,2‐b]quinazolinones
Authors: Bernáth GÁBor , Miklós Ferenc , Stájer GÉZa , Sohár PÁL , Böcskei Zsolt , Menyhárd DÓRa
Published: March 2009

By the reaction of anthranilic hydrazide 1 with cis‐2‐(p‐methylbenzoyl)‐1‐cyclohexanecarboxylic acid 2a or diendo‐3‐(p‐methylbenzoyl)bicyclo[2.2.1]heptane‐2‐carboxylic acid 2b, fused tetra‐ and pentacyclic ring systems 3a, b were prepared, trans‐2‐Amino‐1‐cyclohexanecar‐bohydrazide 4b was reacted with 3‐(p‐chlorobenzoyl)propionic acid 5 to yield the pyridazino[6,1‐b]quinazolinone 6. From the reaction of cis‐2‐amino‐1‐cyclohexanecarbohydrazide 4a with 2a, three isomeric partially saturated 8H‐phthalazino[1,2‐b]quinazolin‐8‐ones 7a‐c were formed. The reaction of diexo‐2‐aminobicyclo[2.2.1]heptane‐3‐carbohydrazide 4c and 2a furnished the pentacyclic derivatives 8 and 9 containing a 3‐aryl‐4,5‐dihydropyridazine or 3‐arylhexahydropyridazine ring C with cis annelated C/D rings. The formation of 8 and 9 involving different ring systems can be rationalized by two reaction pathways: (i) in the bislactam 9 the carboxyl group acylates the hydrazide, while (ii) in 8 it forms a pyridazine ring with the cyclic amino group by cyclocondensation. The structures of the products were elucidated by 1H and 13C nmr methods, including DEPT, DNOE and 2D‐HSC measurements.
Synthesis of 4‐Aryl‐3‐(2‐chromonyl)‐2‐pyrazolines by the 1,3‐dipolar cycloaddition of 2‐styrylchromones with diazomethane
Authors: Pinto Diana C. G. A. , Silva Artur M. S. , Almeida Lúcia M. P. M. , Cavaleiro José A. S. , Lévai Albert , Patonay Tamás
Published: March 2009

The first reported 1,3‐dipolar cycloaddition of 2‐styrylchromones with diazomethane afforded 4‐aryl‐3‐(2‐chromonyl)‐2‐pyrazolines. However, 3‐aryl‐4‐(2‐chromonyl)‐1‐pyrazolines have been also found as minor products of this reaction. These two series of pyrazolines have been fully characterized.
Substituted N‐cyanomethyl‐2‐halo‐N‐methylarenecarboxamides as precursors of 1,4‐benzothiazepines
Authors: Dölling Wolfgang , Perjéssy Alexander , Schaller Ingrid , Kolbe Alfred
Published: March 2009

2‐Halogeno substituted N‐cyanomethyl‐N‐methylbenzamides 1a‐1i were investigated in a correlation analysis by ir spectroscopy to determine the conformational behavior. Compound 1h gives 4‐methyl‐2‐methylthio‐8‐nitro‐5‐oxo‐4,5‐dihydro‐1,4‐benzothiazepine‐3‐carbonitrile 3 by dithiocarboxylation procedure whereas 1b was not able to react to heterocyclic seven‐membered ring system.
Synthesis of 3‐alkenylisoindolin‐1‐ones via palladium(0)‐catalyzed coupling and cyclization between 2‐iodobenzoyl chloride and aldimines
Authors: Cho Chan Sik , Wu Xue , Jiang Li Hong , Shim Sang Chul , Choi Heung‐Jin , Kim Tae Jeong
Published: March 2009

2‐Iodobenzoyl chloride reacts with aldimines in acetonitrile at 100° under carbon monoxide in the presence of a catalytic amount of bis(triphenylphosphine)palladium(II) chloride together with triethylamine to give the corresponding 3‐alkenylisoindolin‐1‐ones in good yields.
Alkylation and arylation of pyrazoles under solvent‐free conditions: Conventional heating versus microwave irradiation
Authors: Almena Inés , Díz‐Barra Enrique , De La Hoz Antonio , Ruiz Juliana , Sínchez‐Migallón Ana , Elguero José
Published: March 2009

The use of sodium hydrogen carbonate under solvent‐free conditions and microwave irradiation is by far the best method for N‐alkylating pyrazoles. The yields are good and the method is devoid of side reactions (quaternization, isomerization, hydrogen halide elimination). Solvent‐free conditions are the only ones that allow us to prepare 1‐substituted pyrazoles from secondary halides. The procedure using quaternary salts in one‐pot provides an interesting alternative for the preparation of 1‐heteroarylpyrazoles.
Definitive structural assignment of condensation products from anthranilamide and 3‐amino‐2‐carbamoylthiophene with ketones. Formation of tetrahydroquinazolinones and their thiophene isosteres
Authors: Klemm Leroy H. , Weakley Timothy J. R. , Gilbertson Robert D. , Song Yang‐Heon
Published: March 2009

Products formed from dehydrative cyclization of cyclopentanone, cyclohexanone, and cycloheptanone with anthranilamide (2) under neutral or acidic conditions are established as the spiro compounds 2,2‐polymethylene‐1,2,3,4‐tetrahydroquinazolin‐4‐ones 6 by means of (a) the presence of a 13C nmr signal at 66–79 ppm for atom C‐2 and (b) X‐ray crystallography on the tetramethylene compound 6a. Analogously, products from reactions of these cycloalkanones with 3‐amino‐2‐carbamoylthiophene are now shown by 13C nmr spectra to have structures isosteric to 6, i.e. 5,5‐polymethylene‐4,5,6,7‐tetrahydrothieno[2,3‐e]pyrimidin‐7‐ones 5, rather than the chelate ring structures previously proposed. Additionally, conflicting literature reports on product 3 from reaction of acetone with 2 are partially clarified. Correlation of 13C chemical shifts in systems 3, 5, and 6 is presented.
Synthesis of 7H‐tetrazolo[1,5‐c]pyrrolo[3,2‐e]pyrimidines and their reductive ring cleavage to 4‐aminopyrrolo[2,3‐d]pyrimidines
Authors: Dave Chaitanya G. , Shah Rina D.
Published: March 2009

Some new 7,9‐disubstituted 7H‐1,2,3,4‐tetrazolo[1,5‐c]pyrrolo[3,2‐e]pyrimidines5have been synthesized either by diazotization of 4‐hydrazino‐5,7‐disubstituted‐7H‐pyrrolo[2,3‐d]pyrimidines4obtained by hydrazinolysis of 4‐chloro‐5,7‐disubstituted‐7H‐pyrrolo[2,3‐d]pyrimidines3orviaa substitution reaction between3and sodium azide. 5,7‐Disubstituted‐7H‐pyrrolo[2,3‐d]pyrimidin‐4(3H)‐ones2were obtained by cyclocondensation of 2‐amino‐3‐cyano‐1,4‐disubstituted pyrroles1with formic acid which on chlorination using phosphorus oxychloride afforded3. A novel route for the synthesis of 4‐amino‐5,7‐disubstituted‐7H‐pyrrolo[2,3‐d]pyrimidines6by the reductive ring cleavage of5has been reported.
Synthesis of 7‐benzoxazol‐2‐yl and 7‐benzothiazol‐2‐yl‐6‐fluoroquinolones
Authors: Richardson Thomas O. , Shanbhag Vinayak P. , Adair Kimberly , Smith Shantel
Published: March 2009

The fluoroquinolones, 7‐benzoxazol‐2‐yl‐1‐ethyl‐6‐fluoro‐1,4‐dihydro‐4‐oxoquinoline‐3‐carboxylic acid and 7‐benzothiazol‐2‐yl‐1‐ethyl‐6‐fluoro‐1,4‐dihydro‐4‐oxoquinoline‐3‐carboxylic acid, were synthesized. The compounds were obtained by use of the Gould‐Jacobs route to the quinoline ring system. The required anilines, 3‐benzoxazol‐2‐yl‐4‐fluorophenylamine and 3‐benzothiazol‐2‐yl‐4‐fluorophenylamine were obtained by the cyclodehydration reaction of 5‐amino‐2‐fluorobenzoic acid with 2‐aminophenol or 2‐aminothiophenol respectively using polyphosphoric acid.
First synthesis of 5,6‐dihydro‐4H‐furo[3,2‐f]pyrrolo‐ [1,2‐a][1,4]diazepines
Authors: Feng Xiao , Lancelot Jean‐Charles , Gillard Alain‐Claude , Landelle Henriette , Rault Sylvain
Published: March 2009

The synthetic pathway leading to 5,6‐dihydro‐4H‐furo[3,2‐f]pyrrolo[1,2‐a][1,4]diazepines is described in four steps starting from α‐bromophenones via 2‐amino‐3‐furonitriles.
Synthesis and spectroscopic properties of 4‐(4‐carboxyphenyl)‐3,3′,5′‐trimethyl‐2,2′‐pyrromethen‐1,1′‐BF2 complex and its methyl ester
Authors: Cheng Lingjiang , Lightner David A.
Published: March 2009

A new, strongly absorbing red dipyrrole chromophore 1 suitable for exciton coupling studies has been synthesized and shown to exhibit an intense absorption (ϵ˜ 57,000) at λ (max) ˜520 nm and a strong fluorescence at λ (em) ˜555 nm.