A facile and efficient approach for the synthesis of 3-arylthiazol-2(3H)-one

A facile and efficient method for synthesis of 3-arylthiazol-2(3H)-one through the reaction of acyl azide and 1,4-dithiane-2,5-diol was reported. This reaction proceeded at 80?°C at first and then in acidic condition at room temperature, to afford products in good yields for a wide range of substrates and a possible mechanism has also been proposed.     

One-Pot Synthesis and Fungicidal Activities of Derivatives of Imidazo [2,1-b]-1,3,4-thiadiazol-5(6H)-one

The isothiocyanates 2, obtained from aza-Wittig reactions of vinyliminophosphoranes 1 with CS ₂ , reacted with hydrazine to give 3-amino-2-thioxo-4-imidazolidinones 4. One-pot reactions of 4, aromatic isocyanates, Ph ₃ P, C ₂ Cl ₆ , and Et ₃ N generated imidazo[2,1-b]-1,3,4-thiadiazol-5(6H)-ones 7. Compound 7 exhibited good fungicidal activities, especially against Sclerotinia sclerotiorum de Bary and Botrytis Cinerea Pers.     

One-pot synthesis of 3-(2-cyanophenyl)quinazolin-4(3H)-one

Anthranilonitrile reacting with formic acid at room temperature for three days gave 64% of 3-(2-cyanophenyl)quinazolin-4(3H)-one. Under similar conditions anthranilic acid. 4-nitroaniline, and 2,5-dichloroaniline were N-formylated in good yields.Institute of Organic Chemistry and Technology, Silesian Technical University, Krzywoustego, 4, 44–100 Gliwice, Poland; e-mail: wojtex@zeus.polsl.gliwice.pl. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 922–924, July, 2000.     

The addition reaction of acrylonitrile and methylacrylate toN-(5R-1,3,4-thiadiazol-2-yl)dithiocarbamates

A new type of dithiocarbamic acid derivatives,S-(2-X-ethyI) ethers ofN-(5R-1,3,4-thiadiazol-2-yl)-dithiocarbamic acids (X = CN, COOMe), has been synthesized by the reaction of sodiumN-(1,3,4-thiadiazol-2-yl) dithiocarbamates with acrylonitrile and methylacrylate.Deceased.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 749–750, April, 1994.     

Interaction of 5-Aryl-1,3,4-oxadiazoline-2(3H)-thiones wth N-Substituted Chloroacetamides

The reactions of some 5-aryl-1,3,4-oxadiazoline-2(3H)-thiones (aryl = phenyl, 4-bromophenyl, 4-methylphenyl, 2,4-dichlorophenyl) with N-alkyl- and N-arylchloroacetamides has been studied. The nature of the substituents in the molecules of the thiones and the chloroacetamides does not affect the direction of the reaction but does affect the yield of the desired products.     

One-pot three-component reaction for the synthesis of novel series of fully substituted 1,3,4-oxadiazole derivatives bearing pyridine moiety

(N-isocyanimino)triphenylphosphorane, 2-pyridinecarbaldehyde, and aromatic carboxylic acids (benzoic acid, 3-methylbenzoic acid, 4-methylbenzoic acid, 3-methoxybenzoic acid, 1-naphthoic acid, and 2-naphthoic acid) undergo a 1:1:1 addition reaction under mild conditions in a one-pot reaction to afford novel series of fully substituted 1,3,4-oxadiazole derivatives in good yields.     

An efficient synthesis of 3-benzylquinazolin-4(1H)-one derivatives under catalyst-free and solvent-free conditions

Abstract

An efficient and convenient method for the preparation of 3-benzylquinazolin-4(1H)-one derivatives under solvent-free and catalyst-free conditions by the reaction of isatoic anhydride, benzylamine, and aromatic aldehydes was reported. In reported papers, ammonia water, ammonium salt, and aromatic amine were often used to synthesize quinazolin-4(1H)-one derivative, but benzylamine was seldom used in this synthesis. This article offers a green method for the synthesis of 3-benzylquinazolin-4(1H)-one derivative used benzylamine as starting material. This methodology has the advantages of short reaction time, mild reaction conditions, easy work-up, and environmental friendliness.     

The Synthesis of 3-(2'-Hydroxybutyl) isobenzofuran-1 (3H)-one

l（3H】．Isobenzoturans（Dhthalldes】werereDortedtoexhibitawiderangeofbiologicalactivities．Forexample,3－n－butylphthallde（NB）exhibitsantlasthmatlc’,antlconvuls－ant“actlvltles．PenEandZhouhavestudiedonthemetabolismofNBPInrats‘．Theyfoundthat...     

A new and efficient method for the synthesis of 3-(2-nitrophenyl)pyruvic acid derivatives and indoles based on the Reissert reaction

The formation of 3-(2-nitrophenyl)pyruvic acid and its amide and ester derivatives – key compounds for the Reissert indole synthesis – was achieved under various reaction conditions via the acid catalyzed hydrolysis of 5-(2-nitrobenzyliden)-2,2-dimethyl-1,3-oxazolidin-4-one, which is readily available from 3-(2-nitrophenyl)oxirane-2-carboxamide. A new and highly efficient method for the synthesis of indole-2-carboxylic acid derivatives via the intramolecular reductive cyclization of o-nitrophenylpyruvic acid and its amide and ester derivatives was developed using Na₂S₂O₄ in dioxane/water at reflux.     

Practical approach to 2-thioxo-2,3-dihydroquinazolin-4(1H)-one via dithiocarbamate–anthranilic acid reaction

A practical and straightforward protocol has been developed for the preparation of 2-thioxo-2,3-dihydroquinazolin-4(1H)-one derivatives from dithiocarbamate chemistry. The method involves the reaction of anthranilic acid derivatives (2-aminobenzoic acid, 2-aminobenzamide and isatoic anhydride) with various dithiocarbamate derivatives using ethanol as solvent. The main advantages of this protocol include practical simplicity, good to high yields, and ease of product isolation, purification and cheapness of the solvent.     

Synthesis and anti-inflammatory and antimicrobial activities of some novel 2-methylquinazolin-4(3H)-one derivatives bearing urea,thiourea and sulphonamide functionalities

A variety of novel 2-methylquinazolin-4(3H)-one derivatives (1–29) bearing urea, thiourea and sulphonamide functionalities at position 3 of biological interest have been synthesized and screened for their anti-inflammatory (TNF-α and IL-6) and antimicrobial activities (antibacterial and antifungal). “Biological evaluation study revealed that the compounds 3, 4, 6, 9, 16 and 18 were found to have promising anti-inflammatory activity (up to 62–84% TNF-α and 73–92% IL-6 inhibitory activity) at concentration of 10 μM with reference to standard dexamethasone (75% TNF-α and 84% IL-6 inhibitory activities at 1 μM) and 7, 10, 12, 23, 25 and 28 have antimicrobial activity at MIC of 10–30 μg/mL against selected pathogenic bacteria and fungi.”     

6-(3-氨基苯基)-4, 5-二氢哒嗪-3(2H)-酮的合成

以苯、丁二酸酐为原料,经傅克酰基化,硝化,与水合肼反应三步反应合成6-(3-氨基苯基)-4,5-二氢哒嗪-3(2H)-酮(1),总收率为58.3%。由3-(3-硝基苯甲酰基)丙酸(3)合成化合物1的过程中,在雷尼镍(Raney Ni)的催化下与水合肼反应,一步完成了苯环上硝基的还原和成环。重点考察了该步反应的物料配比、反应时间对产率的影响。结果表明,水合肼与化合物3的摩尔比11.7∶1,回流反应4 h,产率为82.7%。     

Heteroannulated Quinazoline and Quinazolinone Derivatives from (Z)-2-[1-Benzamido-2-(3,4,5-trimethoxyphenyl)]vinyl-3,1-benzoxazin-4(3H)-one

The title compound 1 was prepared and allowed to react with a series of nitrogen nucleophiles to afford the quinazoline and quinazolinone derivatives 2–12 and tetrazole derivative 13. The IR, ¹H NMR, ¹³C NMR, and mass spectra of all the synthesized compounds were discussed.     

Catalyst-free three-component approach to efficient synthesis of chromeno[4,3-b]pyrrol-4(1H)-one derivatives

A mild, efficient, and environmentally benign one-pot synthesis of functionalized chromeno[4,3-b]pyrrol-4(1H)-ones by a three-component domino reaction of 4-aminocoumarins, arylglyoxal monohydrates, and 1,3-dicarbonyl compounds in refluxing ethanol without the use of catalyst is reported. The present protocol features operational simplicity, short reaction time, good yields, and the absence of aqueous workup procedure and chromatographic separation.     

Synthetic studies on 3-arylquinazolin-4-ones: intramolecular nucleophilic aromatic substitution reaction of 2-carboxamido-3-arylquinazolin-4-ones and its application to the synthesis of secondary aryl amines

The general synthesis and a novel intramolecular nucleophilic aromatic substitution (S_NAr) reaction of 2-carboxamido-3-arylquinazolin-4-ones, a potentially useful scaffold in the field of medicinal chemistry, are described. The synthetic utility of the S_NAr reaction as a tool for the synthesis of secondary aryl amines, including diaryl amines, is also demonstrated.     

The reaction of (N-isocyanimino)triphenylphosphorane with benzoic acid derivatives: a novel synthesis of 2-aryl-1,3,4-oxadiazole derivatives

The reactions of benzoic acid derivatives with (N-isocyanimino)triphenylphosphorane proceed smoothly at room temperature to afford 2-aryl-1,3,4-oxadiazoles in high yields.     

无溶剂条件下方便、有效的方法合成3-氰基-2-吡啶酮衍生物

芳醛、丙酮和氰乙酰胺为原料,氢氧化钠为催化剂,在无溶剂条件下加热反应有效地合成2-吡啶酮衍生物,本方法具有反应时间短、条件温和、处理简单和环境友好等优点.     

3-亚甲基六氢苯并呋喃-2(3H)-酮的简便合成

以氧化环己烯为原料,在正丁基锂作用下与乙腈经开环反应制得2-羟基环己基乙腈(2);2依次经水解、内酯化、二甲胺甲基化、甲基化和Hofmann降解反应合成了α-亚甲基-γ-丁内酯类化合物--3-亚甲基六氢苯并呋喃-2(3H)-酮,总收率30.4%,其结构经¹H NMR,¹³C NMR和HR-MS(EI)确证。     

Synthesis and anti-HBV activity of novel 5-substituted pyridin-2(1H)-one derivatives

<正>Four novel 5-substituted pyridine-2(1H)-one derivatives were designed and synthesized by using addition-elimination reactions.The structures of these novelly synthesized compounds were verified by ~1H NMR,ESI-MS and single crystal X-ray diffraction.Furthermore,all four compounds(most notably compound 7a) were found to be highly efficient against hepatitis B virus (HBV) in cultured HepG2 2.2.15 cell,making them promising drug candidates for potential bioactive molecule against hepatitis B.