Pyrrolidine-2,3-dione, 1-allylpyrrolidine-2,3-dione and 1-ethoxypyrrolidine-2,3-dione

Authentic pyrrolidine-2,3-dione has been prepared by two different routes. It is shown that the material previously reported is actually a hydrolysis product, 4-amino-2-oxobutyric acid. 1-Allyl- and 1-ethoxypyrroli-dine-2,3-dione have been prepared as N-protected pyrrolidine-2,3-diones potentially useful in synthesis.     

Synthesis, reactions, and biological activity of 1,4-benzothiazine derivatives

Abstract  

6,7-Dimethoxy-2H-1,4-benzothiazin-3(4H)-one reacts with dimethylformamide dimethylacetal (DMF-DMA) to give the novel enaminone 2-(dimethylaminomethylene)-6,7-dimethoxy-2H-1,4-benzothiazin-3(4H)-one. The reaction of the latter with various active methylene compounds afforded pyrido[3,2-b][1,4]benzothiazines. Also, coupling of the enaminone with diazotized aniline derivatives gave 2-(arylhydrazono)-6,7-dimethoxy-2H-1,4-benzothiazin-3(4H)-ones. Spectral data indicated that the latter compounds exist predominantly in the hydrazone tautomeric form. In addition, coupling of the enaminone with diazotized heterocyclic amines afforded tetra- and pentaheterocyclic ring systems. The antitumor and antimicrobial activity of some of the synthesized compounds was screened.     

无溶剂条件下5,6-二取代-2,3-吡啶二酮的合成

在无溶剂条件下, 由3-羟基-2(1H)-吡啶酮与取代苯胺在NaIO₃作用下合成了一系列5,6-二取代-2,3-吡啶二酮, 产物结构由元素分析, ¹H NMR, MS, IR得到确认. 该方法具有反应条件温和、操作简单和产率高等优点.     

Synthesis, reactions, applications, and biological activity of diethanolamine and its derivatives

The review considers recent advances in using diethanolamine (DEA) in the synthesis of amides, polymerization reactions, and synthesis of heterocycles, crown ethers, Mannich bases, and ionic liquids. Biological activity of DEA and its derivatives is also reviewed.     

Pyrazoloquinazoline derivatives: Synthesis,reactions, and biological applications

This review deals with the synthesis, reactions and biological activity of pyrazoloquinazoline derivatives. Some of these reactions have been used successfully to the production of biologically importance compounds. The main purpose of this review is to present a survey of the literature on the chemistry of pyrazoloquinazolines and provides useful applications for these compounds.     

Naproxen derivatives: Synthesis,reactions, and biological applications

This review describes the synthesis and reactions of naproxen derivatives and highlights the effects of compounds containing the naproxen moiety in important biological applications.     

Pyrimidines,Part XXXI . Synthesis,reactions and properties of 6-acyl-1,3-dimethylpyrrolo[2,3-d]pyrimidine-2,4-diones

Acylations of 1,3-dimethyl- ( 1 ) and 1,3,7-trimethylpyrrolo[2,3-d]pyrimidine-2,4-dione ( 2 ) with anhydrides in the presence of trifluoroacetic acid proceed well to give in good yields the corresponding 7-acyl derivatives 3–11 . The 6-trichloroacetyl derivatives 5 and 6 are sensitive towards nucleophiles, which displace the trichloromethyl group easily by formation of the corresponding 6-carboxylic acid derivatives 12–23. The newly synthesized compounds have been characterized by elemental analysis, uv and ¹H nmr spectra and pK_a, determinations.     

Synthesis of tetra-substituted furan derivatives from 1-arylpropane-2,3-diones

1-Arylpropane-2,3-diones 4 gave 2-dimethylamino-3-formyl-4-chloro-5-arylfuran derivatives 7 in the Vilsmeier reaction.     

Synthesis,reactions, and biological activity of 4,5-diarylimidazole-2-thiones (Review)

The data on the methods of synthesis, chemical properties, and biological activities of 4,5-diaryl-imidazole-2-thiones published over the last years till the middle of 2008 are reviewed.     

Organocatalytic direct aldol and nitroaldol reactions between azetidine-2,3-diones and ketones or nitromethane

The reactions of enantiopure azetidine-2,3-diones with unmodified ketones or nitromethane were catalyzed by proline and N-methylephedrine, respectively, to give the corresponding 3-functionalized 3-hydroxy-β-lactams with good yields and total diastereoselectivities. It was observed that the use of both enantiomers of proline or of N-methylephedrine does result in identical levels of stereocontrol in the aldol and nitroaldol reactions.     

Synthesis, reactions and biological activity of 2-substituted 3-cyano-4,6-dimethylpyridine derivatives

The reaction of 2-chloro-4,6-dimethylpyridine-3-carbonitrile with hydrazine hydrate, hydroxylamine, and anthranilic acid afforded the corresponding pyrazolo, isoxazolo, and pyridoquinazoline derivatives. Alkylation of 2-mercapto-4,6-dimethylpyridine-3-carbonitrile with ethyl chloroacetate or phenacyl bromide followed by cyclization in NaOH gave thienopyridine derivatives. Diazotization of ethyl 3-amino-4,6-dimethylthiеno[2,3-b]pyridine-2-carboxylate followed by the reaction with thiourea, guanidine carbonate, and hydroxylamine hydrochloride gave the corresponding thienopyridine derivatives. The biological activity of some new compounds has been discussed. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 43–51, Januar, 2009.     

Synthesis,structutre and biological activity of substituted [16α,17α]cyclopropapregn-4-ene-3,20-diones

Aryldiazomethanes generated by vacuum thermolysis of arenecarbaldehyde tosylhydrazone sodium salts react stereospecifically with 16-dehydropregnenolone acetate. Subsequent decomposition of the pyrazoline adducts yielded hitherto unknown substituted [16α,17α]-cyclopropaprogesterones bearing the aryl substituents at the position 3′. Interaction of such cyclopropaprogesterones with progesterone receptor from rat uterine cytosol was studied.     

Studies of the reactions between indole-2,3-diones (isatins) and 2-aminobenzylamine

Reflux of equimolecular amounts 2-aminobenzylamine and isatins in acetic acid produced indolo[3,2-c]quinolin-6-ones in good yields. A proposed mechanism involving initial formation of a spiro compound is given. This isolable intermediate subsequently rearranges via a sequential isocyanate ring opening and a cyclisation process to a urea derivative which finally cyclized to the indolo[3,2-c]quinolin-6-ones. The urea derivative could be prepared separately and cyclized selectively to indolo[3,2-c]quinolin-6-one. Reaction of N-acetylisatin with 2-aminobenzylamine at room temperature yielded the 1,4-benzodiazepinone 3-(2-acetamidophenyl)-1,5-dihydro-1,4-benzodiazepin-2-one whereas its isomer 2(2-acetamidophenyl)-4,5-dihydro-1,4-benzodiazepin-3-one was obtained from 2-(2-acetylaminophenyl)-N-(2-aminobenzyl)-2-oxoacetamide in acetic acid at room temperature.The previously unknown linear isomer of indolo[3,2-c]quinolin-6-one, i.e. indolo[2,3-b]quinolin-11-one, has been prepared by thermal (260°C) cyclization of methyl 2-phenylamino indole-3-carboxylate, which in turn was prepared in two steps from methyl indole-3-carboxylate.     

Synthesis of substituted pyrrolo[2,3-D]pyrimidine-2,4-diones

A facile route for the synthesis of substituted pyrrolo[2,3-d]pyrimidine-2,4-diones from substituted 2-amino-3-cyano-4-methylpyrroles is reported.     

Reactions of Acylpyruvic Acids and 2,3-Dihydrofuran-2,3-diones with 2,3-Diaminopyridine

Acylpyruvic acids readily react with 2,3-diaminopyridine to form (Z)-3-acylmethylene-1H-3,4-di- hydropyrido[2,3-b]pyrazin-2-ones. 5-Aryl-2,3-dihydrofuran-2,3-diones which can be regarded as lactones derived from -enolized aroylpyruvic acids react with 2,3-diaminopyridine under mild conditions, yielding regioisomeric (Z)-2-aroylmethylene-4H-1,2-dihydropyrido[2,3-b]pyrazin-3-ones. The structure of the products and reaction chemoselectivity are discussed.     

Quinoxaline-2,3(1H,4H)-dithione: Synthesis and reactions

Quinoxaline-2,3(1H,4H)-dithione can be synthesized efficiently through the thionation of quinoxaline-2,3(1H,4H)-dione with phosphorous pentasulfide. It can also be obtained by reaction of 2,3-dichloroquinoxaline with thiourea or sodium hydrogen sulfide. The most common reactions of quinoxaline-2,3(1H,4H)-dithione involve deprotonation and electrophilic attack at the sulfur atoms to give various substituted derivatives and poly-fused heterocyclic ring systems. The current review aims to provide a survey of the developments in quinoxaline-2,3(1H,4H)-dithione chemistry until 2016.     

Synthesis and Photochemistry of syn- and anti-9,10-Epoxy-1, 4-dihydro-1,4-ethanonaphthalene-2,3-diones

The title epoxydiketones were prepared stereoselectively, direct epoxidation of 3a-c with MCPBA produced syn isomers la-c whereas epoxidation of 4a-d followed by saponification of the spirolactone rings gave anti isomers 2a-c. The stereochemistry of 1a and 2a was established by X-ray diffraction, whereas that of the remaining epoxydiketones was determined from the correlation of visible, ¹H, and ¹³C NMR spectral data; the differences between spectra of the corresponding syn and anti isomers are explained in terms of through-space interaction and steric effects. Photolysis of syn isomers 1a-c afforded the corresponding naphthalenes 8a-c in almost quantitative yields; in contrast, irradiation of anti isomers 2a-c gave complicated mixtures. The quantum yield of disappearance of 1a was 52 times that of 2a. Reaction mechanisms are proposed to account for the product formation. The differences in the photochemical behavior of the title syn and anti isomers are rationalized in terms of stereoelectronic effects of the epoxy rings in the syn isomers.     

Synthesis of functionalized 2,3-dihydroisoxazoles by domino reactions in water and unexpected ring-opening reactions of 2,3-dihydroisoxazoles

α,α-Dicyanoolefins react with hydroxylamine to afford 2,3-dihydroisoxazoles (2,3-dihydroisoxazoles can be easily isolated by filtration) in excellent yields under mild and environmentally benign conditions. A one-pot reaction in tandem with an unexpected ring-opening of 2,3-dihydroisoxazoles has been developed as well.