bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of 10‐(4‐methyl‐1‐piperazinyl)thieno[3,2‐b][1,5]benzothiazepines
Authors: Corral Carlos , Lasso Ana , Lissavetzky Jaime , Valdeolmillos Ana M. 
Published: April 2009

AbstractA series of the title compounds has been synthesized by two alternative methods in order to study their potential neuroleptical activity and to compare it with the pharmacological data already obtained for compounds of other isomeric or related series.
Synthesis of 10‐(4‐methyl‐1‐piperazinyl)thieno[3,2‐b][1,5]benzoxazepines
Authors: Corral Carlos , Lissavetzky Jaime , Valdeolmillos Ana M. 
Published: April 2009

AbstractA series of the title compounds has been synthesized starting from methyl 3‐hydroxythiophene‐2‐carboxylate. Its condensation with 2,4‐dinitrochlorobenzene provides through compound 4e a way to introduce 7‐substituents by means of diazonium salts reactions.
Reaction of 5‐(3,4‐dimethoxyphenyl)pyrazine‐2,3‐dicarbonitrile with alcohol in the presence of base
Authors: Tsuzuki Koichi , Tada Masaru 
Published: April 2009

Abstract5‐(3,4‐Dimethoxyphenyl)pyrazine‐2,3‐dicarbonitrile reacts with methanol to give addition products, 3‐methoxyiminopyrazine‐2‐carbonitrile and 2‐methoxyiminopyrazine‐3‐carbonitrile derivatives, and/or substitution products, 3‐methoxypyrazine‐2‐carbonitrile and 2‐methoxypyrazine‐3‐carbonitrile derivatives. The selectivity between the addition and substitution depends on solvent polarity, base, and reaction time. The experimental results are accounted for by the equilibrium between the starting dinitrile and the addition products, methoxyiminopyrazine.
Nitrogen bridgehead compounds. Part 55 Synthesis of substituted 7,8‐dihydro‐5H,13H‐indolo[2′,3′:3,4]pyrido[2,1‐b]quinazolin‐5‐ones
Authors: Hermecz István , Pod Benjaminányi , Mészáros Zoltán , Szász György , Kökösi József 
Published: April 2009

AbstractFischer indolization of 6‐arylhydrazono‐6,7,8,9‐tetahydro‐11H‐pyrido[2,1‐b]quinazolin‐11‐ones 1 afforded substituted 7,8‐dihydro‐5H,13H‐indolo[2′,3′:3,4]pyrido[2,1‐b]quinazolin‐5‐ones 3‐12 in high yields.
Oxidation of aldehyde semicarbazones with lead dioxide: Application to the syntheses of 2‐amino‐1,3,4‐oxadiazoles and 2,4‐dihydro‐1,2,4‐triazol‐3‐ones
Authors: Nguyen Thu‐Huong , Milcent René , Barbier Geo 
Published: April 2009

AbstractThe oxidation of aldehyde semicarbazones with lead dioxide in acid media was effected. The 4,4‐disubstituted semicarbazones of aromatic aldehydes afford 2‐amino‐1,3,4‐oxadiazole derivatives. The 2,4‐disubstituted semicarbazones give 2,4‐dihydro‐1,2,4‐triazol‐3‐ones, often in higher yields than the known methods. The mechanisms for the formation of these compounds are proposed.
A study of tautomerism in diazonium coupling products of 4‐hydroxycoumarin
Authors: Shawali Ahmad S. , Harb Nagwa M. S. , Badahdah Khadiga O. 
Published: April 2009

AbstractThe spectra (1H nmr, ir and uv) of a series of 3‐arylazo‐4‐hydroxycoumarins 1a‐m indicate that such compounds exist predominantly in the keto hydrazone form 1A both in solid state and in solution. The acid dissociation constants of the series studied were determined spectrophotometrically in 80 vol% ethanol‐water mixture at 27° and ionic strength of 0.1. The results of the correlations of these constants by Hammett and Yukawa‐Tsuno equations exclude the presence of the hydroxyazo form 1B in equilibrium with 1A in agreement with the spectral data. Also, the HMO method has been used to study tautomerism in such compounds. The results are also in full agreement with both the spectral and linear free energy correlations, the hydrazone form 1A being the most stable. It is further shown that both the intermolecular and intramolecular hydrogen bonding favor the hydrazone tautomer.
Derivate von 4,5‐dihydroxypyridonen durch ringerweiterung
Authors: Stachel Hans‐Dietrich , Wiesend Bruno , Kreiner Christine 
Published: April 2009

AbstractDie epimeren Bromhydrine 13/14 sowie deren Ether 5/6 lagern in Gegenwart von Silberionen zu den 5‐Hydroxypyridonen 15 bzw. deren Ketalen 9 um. Bei den Bromhydrinethern 5/6a und b tritt diese Umsetzung auch mit Methylat ein. Unter diesen Reaktionsbedingungen verläuft die Ringerweiterung vermutlich über bicyclische Aziridine, von denen 7 isoliert werden konnte. Die N‐methylierten Verbindungen 5c/6c, die nicht in gleicher Weise reagieren können, bilden mit Methylat das 6‐Methoxypyridon 12.
Synthesis of 4‐alkyl‐3‐pyridinols from 3‐benzyloxypyridine
Authors: Comins Daniel L. , Stroud Eric D. 
Published: April 2009

AbstractThe addition of Grignard reagents to the 1‐phenoxycarbonyl salt of 3‐benzyloxypyridine and a catalytic amount of cuprous iodide afforded 4‐alkyl‐3‐benzyloxy‐1‐phenoxycarbonyl‐1,4‐dihydropyridines in good yield. The crude dihydropyridines were aromatized with o‐chloranil to give 4‐alkyl‐3‐benzyloxypyridines, which were debenzylated with hydrogen and 10% palladium on carbon to provide 4‐alkyl‐3‐pyridinols.
Chemoselective reductions of 2‐acyl‐1H‐indole‐3‐carboxaldehydes
Authors: Djurić Stevan W. , Herbert Richard B. , Holliman Frederick G. 
Published: April 2009

AbstractA novel procedure for the chemoselective reduction of 2‐acyl‐1H‐indole‐3‐carboxaldehydes has been developed. Low temperature lithium triethylborohydride reduction affords the indol‐2‐yl carbinol whilst sodium cyanoborohydride reduction in acetic acid affords the 3‐hydroxymethyl analogs. Both processes are high yield, and provide access to intermediates of potential utility for indole alkaloid synthesis.
About the synthesis of [1,2]diazepinoindole derivatives from ethyl 2‐(1‐methylindole)acetate, 2‐indole and 3‐indoleacetohydrazones
Authors: Monge A. , Palop J. A. , Goñí T. , Martínez A. , Fernández‐Alvarez E. 
Published: April 2009

AbstractThe Vilsmeier‐Haack reaction with ethyl 2‐(1‐methylindole)acetate and N,N‐Dimethylamides/phosphorus oxychloride gave (65–85%) of ethyl 2‐(3‐acyl‐1‐methylindole)acetates 2, which when boiled with hydrazine yielded about 90% of 4,5‐dihydro‐6‐methyl‐4‐oxo‐3H[1,2]diazepino[5,6‐b]indoles 3. The attempted cyclization of 2‐(1‐methylindole)acetohydrazones 6 with acyl (acetyl and benzoyl) chlorides/triethylamine, to [1,2]diazepino[5,6‐b]indole derivatives was fruitless and the bis(acyl)hydrazones 9 were obtained. Several transformations of 9 are reported. Similarly, the attempted cyclization of 3‐indoleacetohydrazones 14 with acetyl chloride/triethylamine to [1,2]diazepino[4,5‐b]indole derivatives was also fruitless and the bis(acyl)hydrazones 16 were again obtained.
Long range optimized two‐dimensional proton‐carbon chemical shift correlation. Application in the total assignment of the 1H‐ and 13C‐NMR spectra of 9‐methylphenanthro[4,3‐a]dibenzothiophene
Authors: Quast Michael J. , Ezell† Edward L. , Martin Gary E. , Lee Milton L. , Tedjamulia Marvin L. , Stuart John G. , Castle Raymond N. 
Published: April 2009

AbstractThe utilization of the long range optimized proton‐carbon chemical shift correlation experiment in the total assignment of the proton and carbon nmr spectra of 9‐methylphenanthro[4,3‐a]dibenzothiophene is described. The experiment was employed in concert with conventional proton‐carbon chemical shift correlation, heteronuclear relayed coherence transfer and broad band homonuclearly decoupled proton‐carbon chemical shift correlation experiments. The experiments in combination offer a useful alternative to the 13C‐13C double quantum coherence experiments, providing significantly better sensitivity and nearly the same capabilities.
Formation of 3‐phenylhydrazono‐3‐aroylpropionamides from the reaction of 5‐aroyl‐3(2H)‐isothiazolones with phenylhydrazine
Authors: Tsolomitis A. , Sandris C. 
Published: April 2009

AbstractReaction of 2‐substituted‐5‐aroyl‐3(2H)‐isothiazolones 1 with phenylhydrazine in refluxing ethanol was found to give sulfur‐free products, which were characterized as 3‐phenylhydrazono‐3‐aroyl‐N‐substituted‐pro‐pionamides 4. Acid hydrolysis of the 3‐benzoyl compounds 4 was shown to yield 1‐phenyl‐3‐benzoyl‐2‐pyrazolin‐5‐one (7), whose structure was confirmed by an independent synthesis starting with the chloride of 1‐phenyl‐5‐methoxypyrazole‐3‐carboxylic acid (10).
Facile dibenzoylation of picoline
Authors: Suzuki Toshinobu , Mitsuhashi Keiryo 
Published: April 2009

AbstractIn the presence of triethylamine, 2‐ and 4‐picolines reacted with an excess of benzoyl chloride in refluxing acetonitrile to give the corresponding 1‐benzoyl‐phenacylidenedihydropyridines. The difference in reactivity between 2‐ and 4‐picoline toward such a dibenzoylation was studied from the conversion rates under various conditions with hplc. It was also clarified that the dibenzoylation proceeded via the intermediate phenacylpyridine and a plausible reaction scheme has been proposed, considering the significant role of triethylamine.
Mechanism of the condensation reaction between 1‐aryl‐ and heteroaryl‐1,4‐dihydro‐3(2H)‐isoquinolinones and aldehydes
Authors: Hazai László , Deák Gyula , Tamás József , Doleschall Gábor , Tóth Gabor 
Published: April 2009

Abstract4‐Benzylidene‐1‐phenyl‐1,4‐dihydro‐3(2H)‐isoquinolinone, the intermediary product of the carbonyl condensation reaction between 1‐phenyl‐1,4‐dihydro‐3(2H)‐isoquinolinone and benzaldehyde, rearranges in the presence of an equivalent quantity of sodium hydride into 4‐benzyl‐1‐phenyl‐3(2H)‐isoquinolinone. As the possibility of the migration of the hydrogen at C‐1 in the form of a proton or a hydrogen atom (radical reaction) was excluded, the mechanism of the rearrangement could be depicted as an intermolecular hydride anion migration. In case of the 1‐(4‐pyridyl)‐ and 1‐(3‐pyridyl)‐1,4‐dihydro‐3(2H)‐isoquinolinones, however, the rearrangement can be carried out also in polyphosphoric acid and in this case a proton loss‐proton gain mechanism was proved.
Pyridazino[3,4‐b]quinoxalines and their reduced derivatives. Preparation and structure
Authors: Armand Joseph , Armand Yvette , Boulares Line , Bellec Christian , Pinson Jean 
Published: April 2009

AbstractThe reaction of o‐phenylenediamine with a β‐ketoacid, leads in most cases to quinoxalinones. Their structure has been determined as well as that of their corresponding hydrazones. The reaction of hydrazine with these quinoxalinones gives dihydropyridazino[3,4‐b]quinoxalines, the structure of which has been ascertained. It has been shown that among the six possible formulas, the only 1,2‐dihydro structure fits with the spectroscopic data. On the contrary, N‐substituted o‐phenylenediamines lead to 2,10‐dihydro derivatives. The electrochemical behavior of the 2,10‐dihydro‐10‐methyl‐3‐phenylpyridazino[3,4‐b]quinoxaline has been investigated. It has also been shown that the 3,4,6‐trichloropyridazine reacts with o‐phenylenediamines to give 5,10‐dihydropyridazino[3,4‐b]quinoxalines. These compounds can be oxidized to give the new heterocycle pyridazino[3,4‐b]quinoxaline.
Chemistry of quinazolines: Reinvestigation of the action of hydrazine on thioxo derivatives
Authors: Badawy Mohamed A. , Abdel‐Hady Sayed A. L. , Ibrahim Yehia A. , Kadry Azza M. 
Published: April 2009

AbstractThe action of hydrazine on 2‐mercapto and 2‐alkylmercaptoquinazolin‐4‐ones is reinvestigated. The structure of the isolated products have been revised.
Synthesis of 3,3′‐(1,6‐hexanediyl)bis‐pyrimidine derivatives and 3,4‐dithia[6.6](1.3)pyrimidinophane
Authors: Kinoshita Toshio , Odawara Shirou , Fukumura Keiko , Furukawa Sunao 
Published: April 2009

AbstractSeveral 3,3′‐(1,6‐hexanediyl)bis[6‐methyl‐2,4(1H,3H)‐pyrimidinedione] derivatives (4a, 4b, and 4c) were synthesized from 1,6‐(hexanediyl)bis[6‐methyl‐2H‐1,3‐oxazine‐2,4(3H)‐dione] (3). Compound 4c was converted to 6, which reacted with thiourea giving thiuronium salt 7. 3,3′‐(1,6‐Hexanediyl)bis [1‐(2‐mercaptoethyl)‐6‐methyl‐2,4(1H,3H)‐pyrimidinedione] (9) was obtained by the hydrolysis of 7, and then 9 was oxidized to 12,22‐dimethyl‐3,4‐dithia[6.6] (1.3)‐1,2,3,4‐tetrahydro‐2,4‐dioxopyrimidinophane (10).
3,4‐Dihydro‐2‐phenyl‐2H‐pyrano[2,3‐b]pyridines. Novel aza analogs of flavans
Authors: Bargar T. M. , Wilson T. , Daniel J. K. 
Published: April 2009

AbstractComplementary approaches to the synthesis of the title compounds 1 are described. Metallation of 3,5‐di‐bromo‐2‐methoxypyridine (5b) by bromine/lithium exchange gave selectively the 3‐lithio intermediate 6 which was trapped with substituted cinnamaldehydes 7, providing allylic alcohols 8 in good yields. Methyl ether cleavage and concomitant cyclization occurred on exposure to concentrated hydrobromic acid in hot acetic acid. The resulting 2‐phenyl‐2H‐pyrano[2,3‐b]pyridines were hydrogenated over Raney nickel to the title compounds which had antiviral activity. Alternatively, 1 were synthesized by Heck reaction of appropriately substituted 3‐halo‐2‐methoxypyridines (5 or 24) with vinyl carbinol 15 to furnish ketones 16 or 26 which, upon reduction of the carbonyl group, were cyclized directly to 1.
Antimicrobial activity of 3‐(substituted methyl)‐2‐phenyl‐4H‐l‐benzothiopyran‐4‐ones
Authors: Nakazumi Hiroyuki , Ueyama Tamio , Kitao Teijiro 
Published: April 2009

AbstractA series of 3‐(substituted Methyl)‐2‐phenyl‐4H‐l‐benzothiopyran‐4‐ones (thioflavones) and thioflavone 1,1‐dioxides was prepared to test for antimicrobial activity and for antitumor activity. It was shown that an introduction of a substituted methyl group in the 3‐position of thioflavone resulted in significant antimicrobial activity against Trichophytons. 3‐(Acetoxymethyl)thioflavone shows the most antimicrobial potency in vitro against Trichophyton mentagrophytes. Most of the thioflavone 1,1‐dioxides showed antimicrobial activity against fungi. Five of the 40 related compounds demonstrated weak antitumor activity against P‐388 lymphocytic leukemia.
Heterocycles of biological importance. Part 2. Novel synthesis and pharmacological evaluation of 5‐amino‐3‐alkyl‐1‐(2‐pyridyl)pyrazoles and 5‐amino‐3‐phenyl‐1‐(2‐pyridyl)pyrazole from allenic or acetylenic nitriles and 2‐hydrazinopyridine
Authors: Fomum Z. Tanee , Ifeadike P. Ngozi 
Published: April 2009

Abstract2‐Hydrazinopyridine reacts with allenic and acetylenic nitriles to give 5‐amino‐3‐alkyl‐1‐(2‐pyridyl)pyrazoles 6 in excellent yields. One of these compounds, 6e has been shown to possess anticonvulsant and anti‐electroshock properties. Phenyl propynenitrile also reacts with hydrazinopyridine to give 5‐amino‐3‐phenyl‐1‐(2‐pyridyl)pyrazole (11) in quantitative yield.
Syntheses and reactions of 2‐halo‐5‐thiazolecarboxylates
Authors: Lee Len F. , Schleppnik Francis M. , Howe Robert K. 
Published: April 2009

AbstractA variety of 2‐halo‐5‐thiazolecarboxylates was prepared from substituted‐3‐aminoacrylates and 3‐ketoes‐ters. Selective reduction of 2‐chloro‐5‐thiazolecarboxylates 4a, 4i and 4j with sodium borohydride in ethanol provided the corresponding 2‐halo‐5‐thiazolemethanols 27‐29. Nucleophilic displacements on [2‐chloro‐4‐(trifluoromethyl)‐5‐thiazolyl]methyl methanesulfonate (32c) occurred selectively at the 5‐substituent to provide 2‐chloro‐4‐(trifluoromethyl)‐5‐(heteroatom‐substituted‐methyl)thiazoles 32d‐f.
The synthesis and structure of 5‐hydroxy‐2‐methyl‐2‐(2‐pyridinyl)hexahydro‐1,3‐pyrimidine
Authors: Fenton David E. , Moody Richard , Casellato Umberto , Vigato P. A. , Graziani Rodolfo 
Published: April 2009

AbstractThe synthesis and the x‐ray structure of 5‐hydroxy‐2‐methyl‐(2‐pyridinyl)hexahydro‐1,3‐pyrimidine are reported. The compound was prepared by reaction of 2‐acetylpyridine and 1,3‐diamino‐2‐hydroxypropane in a 2:1 molar ratio. The colourless crystals are monoclinic, space group P21/c with cell parameters, a = 10.385(5), b = 11.171(5), c = 17.415(6)Å, β = 93.05(37)° for Z = 8. The asymmetric unit of the structure is composed of two independent molecules of the compound which are in the chair form and adopt the same conformation with equatorial ‐OH and ‐CH3 groups and axial pyridine substituents. The packing of the molecule seems to be controlled by two independent hydrogen‐bonding sequences.
Basicity of the nitrogen atom and of the carbonyl function of methyl isonicotinate and 4‐acetylpyridine. An infrared study of the interaction with proton donors
Authors: Kasende O. , Vanderheyden E. , Zeegers‐Huyskens Th. 
Published: April 2009

AbstractThe hydrogen bonded complexes between methyl isonicotinate and 4‐acetylpyridine and phenol derivatives acting as proton donors have been investigated by ir spectroscopy. The thermodynamic parameters (K, — ΔH°, — ΔS°) have been determined. The ir data show that the hydrogen bond interaction occurs at the carbonyl function and at the nitrogen atom of the ring. When the acidity of the proton donor increases, N‐complexation is favoured over carbonyl complexation and with the stronger acid hydrochloric acid, only N‐protonated species are observed. The data are compared with those obtained for closely related pyridine derivatives, bearing a X‐C=O substituent and it is shown that the proportion of OH···N and OH···O=C species is related to the basicity of the nitrogen atom of the heterocyclic ring and to inductive and mesomeric effects depending on the nature of X.
Synthesis of heterocyclic compounds XLIX. An unexpected synthesis of isoxazolamines
Authors: Ciller J. A. , Seoane C. , Soto J. L. 
Published: April 2009

AbstractReaction of 3‐aryl‐1‐phenyl‐2‐nitropropenones 1 with potassium cyanide leads to 4‐aryl‐3‐benzoyl‐5‐isoxazo‐lamines 5 in a one‐step process involving the formal reduction of the nitro group followed by nucleophilic attack at the cyano group. Treatment of the isoxazolamine with an aromatic aldehyde yields the corresponding N‐arylideneisoxazolamine.
Annulated 1,2,3‐triazoles. 3. Synthesis of 1,2,3‐triazolo[4,5‐b][1,5]benzoxazepin‐10(9H)‐ones and 10‐(4‐substituted‐1‐piperazinyl)‐1,2,3‐triazolo[4,5‐b][1,5]benzoxazepines
Authors: Nielsen Flemming E. , Pedersen Erik B. 
Published: April 2009

Abstract10‐(4‐Substituted‐1‐piperazinyl)‐1,2,3‐triazolo[4,5‐b][1,5]benzoxazepines 11 were prepared in a three‐step synthesis starting from easily available 5‐chloro‐1,2,3‐triazole‐4‐carbonyl chlorides 7 by titanium tetrachloride catalyzed condensation of N‐(substituted)piperazines with 1,2,3‐triazolo[4,5‐b][1,5]benzoxazepin‐10(9H)‐ones 10 formed by ring closure of the intermediate amides 9. Although lactams 10 were obtained as the sole product of the cyclisation at 80°, the unexpected by‐products 13 and 14 were formed in addition to 10c at 150° from 9c. The 4‐methoxybenzyl group in 11j was easily removed by solvolyses in TFA. Compounds 11d‐f and 11i were tested for psychotropic activity.
Nucleosides. 130. Synthesis of 2′‐Deoxy‐2′‐substituted‐ and 5′‐Deoxy‐5′‐substituted‐ψ‐uridine Derivatives. Crystalline and Molecular Structure of 2′‐Chloro‐2′‐deoxy‐1,3‐dimethyl‐ψ‐uridine. Studies Directed Toward the Synthesis of 2′‐Deoxy‐2′‐substituted‐arabino‐Nucleosides. 1
Authors: Pankiewicz Krzysztof W. , Watanabe Kyoichi A. , Takayanagi Hiroaki , Itoh Tsueno , Ogura Haruo 
Published: April 2009

AbstractA method was developed to prepare 5′‐deoxy‐5′‐substituted‐ψ‐uridine derivatives 4 from 3′,5′‐O‐(1, 1, 3, 3‐tetraisopropyldisiloxanyl)‐1,3‐dimethyl‐ψ‐uridine 1 via a silyl rearrangement reaction. Nucleophilic displacement of the mesyloxy function of 2′‐O‐mesyl‐1,3‐dimethyl‐ψ‐uridine 7 afforded products with the 2′‐substituent in the “down” ribo configuration 8. X‐Ray crystallographic analysis of the 2′‐chloro derivative 8a firmly established the molecular structure of 8 and provided evidence for neighboring group participation of the 4‐carbonyl function of 7 during the nucleophilic reactions.Treatment of 1,3‐dimethyl‐ψ‐uridine 11 with α‐acetoxyisobutyryl chloride afforded a mixture from which two 2′‐chloro‐2′‐deoxy‐C‐nucleosides were obtained. The major product (33% yield) was identical with 8. The minor product (7% yield) was consequently assigned the arabino nucleoside 14. This is the first direct introduction of a 2′‐substituent in the “up” configuration in a preformed pyrimidine nucleoside.
Synthesis and conversions of 3‐(4‐amino‐5‐methyl‐4H‐1,2,4‐triazol‐3‐ylmethylene)‐2‐oxo‐1,2,3,4‐tetrahydroquinoxaline
Authors: Kurasawa Yoshihisa , Okamoto Yoshihisa , Takada Atsushi 
Published: April 2009

AbstractThe reaction of the hydrazone 3a with hydrazine hydrate in DBU/ethanol conveniently gave 3‐(4‐amino‐5‐methyl‐4H‐1,2,4‐triazol‐3‐ylmethylene)‐2‐oxo‐1,2,3,4‐tetrahydroquinoxaline 6. The reactions of 6 with an equimolar and 2‐fold molar amount of nitrous acid afforded 3‐(α‐hydroxyimino‐4‐amino‐5‐methyl‐4H‐1,2,4‐triazol‐3‐ylmethyl)‐2‐oxo‐1,2‐dihydroquinoxaline 9 and 3‐(α‐hydroxyimino‐5‐methyl‐2H‐1,2,4‐triazol‐3‐ylmethyl)‐2‐oxo‐1,2‐dihydroquinoxaline 10, respectively, which were converted into the 3‐heteroarylisoxazolo[4,5‐b]quin‐oxalines 13a,b and 11, respectively. Compound 9 was also cyclized into the 8‐quinoxalinyl‐1,2,4‐triazolo‐[3,4‐f][1,2,4]triazines 14a,b.
Synthesis and degradation of 3‐amino‐3‐(2‐substituted benzimidazol‐1‐yl)‐2‐(2‐phenyl‐1,1‐diazanediylmethyl)‐2‐propenenitrile: Hydroxyl group‐promoted CN bond fission
Authors: Okamoto Yoshihisa , Kurasawa Yoshihisa , Takada Atsushi , Takagi Kaname 
Published: April 2009

AbstractThe reaction of 3‐amino‐3‐(o‐aminoanilino)‐2‐cyano‐2‐propenal phenylhydrazone (2) with orthoesters gave the title compound (3), which was readily converted to 2‐substituted benzimidazole (4) and 5‐amino‐4‐cyano‐1‐phenylpyrazole (5) when heated in 1‐butanol. The degradation mechanisms were proposed.
2‐Amino‐ and 2‐guanidino‐4‐thiazolylpyrimidines
Authors: Lipinski Christopher A. , Craig Rebecca H. , Wright Roger B. 
Published: April 2009

AbstractThe synthesis of the four possible 2‐amino‐ and 2‐guanidino‐ 4‐(2‐amino‐ and 2‐guanidinothiazolyl)pyrimi‐dines is described and pKa. values are calculated. Guanidinopyrimidines are more basic than guanidinothiazoles. However, the reverse is true of the corresponding amino heterocycles; the amino thiazole is more basic than the amino pyrimidine.
New synthesis of α‐nitroalkyl‐ and α‐nitroaralkylcarboxylic esters from α‐nitroalkyl‐ and α‐nitroaralkyl‐2‐oxazolines
Authors: Feuer Henry , Bevinakatti Hanamanthsa S. , Luo Xuan‐Gan 
Published: April 2009

Abstract2‐Nitroalkyl‐ and 2‐nitroaralkyl‐2‐oxazolines are readily converted, in one step, to α‐nitroalkyl‐ and α‐nitroaralkylcarboxylic esters on treatment with the appropriate alcohol and trifluoroacetic acid (TFA). The initial products of the ring cleavage are the TFA salts of the ammonioalkyl esters of α‐nitroalkyl‐ and α‐nitroaralkylcarboxylic acids. These salts undergo facile transesterification to the α‐nitrocarboxylic esters on refluxing with the appropriate alcohol.
Synthesis and reactions of heterocyclic 2,3‐epoxypropionitriles with pyrrolidine
Authors: Agarwal Kamlesh C. , Knaus Edward E. 
Published: April 2009

AbstractThe Darzen's reaction of 2‐(3‐)pyridinecarboxaldehydes5with chloroacetonitrile yielded a mixture of stereoisomerscis‐6andtrans‐3‐(pyridinyl)‐2,3‐epoxypropionitriles7in a ratio of approximately 1:1. Oxidation ofcis‐6andtrans‐7afforded the correspondingcis‐8andtrans‐3‐(1‐oxidopyridinyl)‐2,3‐epoxypropionitriles9in good yield. The reaction of8aand9awith pyrrolidine at 25° gave the respectivethreo‐10anderthyro‐2‐(1‐pyrrolidino)‐3‐hydroxy‐3‐(1‐oxido‐2‐pyridinyl)propionitrile (11). A number of selected compounds (7‐9a‐b) were found to be inactive in the P388 Lymphocyctic screen.
Studies on the nef reaction induced by organic bases
Authors: Akhtar Mohammad Shamim , Sharma Vishnu Lal , Bhaduri Amiya Prasad 
Published: April 2009

AbstractStudies of the Nef reaction in the presence of primary, secondary and tertiary amines have been described. A convenient synthesis of N‐substituted pyrroles and 3,6‐dimethyl‐4‐hydrazinocarbonyl‐5‐(4‐amino‐3‐nitrophenyl)‐pyridazine 16 has been developed.
Synthesis of benzimidazole derivatives as potential H1‐antihistaminic agents
Authors: Iemura Ryuichi , Kawashima Tsuneo , Fukuda Toshikazu , Ito Keizo , Tsukamoto Goro 
Published: April 2009

AbstractSeveral types of benzimidazole derivatives were prepared and were screened forH1‐antihistaminic activity. Most of the compounds showed potent antihistaminic activityin vitro.Among them 2‐[(1‐piperazinyl)methyl]‐benzimidazoles14and 2‐[(1‐homopiperazinyi)methyl]benzimidazoles15exhibited potent activity alsoin vivo.