Synthesis of Some New Thiazoles and Pyrazolo[1,5-a]pyrimidines Containing an Antipyrine Moiety

Ethyl 2-{2-[4-(2,3-dimethyl-5-oxo-1-phenyl-3-(pyrazolin-4-yl)]-2-cyano-1-(phenylamino)vinylthio}-acetate, 2-[4-(2,3-dimethyl-5-oxo-1-phenyl-(3-pyrazolin-4-yl))(1,3-thiazol-2-yl)]2-(4-oxo-3-phenyl-(1,3-thiazoilidin-2-ylidene))ethanenitrile, 2-[4-(2,3-dimethyl-5-oxo-1-phenyl(3-pyrazolin-4-yl))(1,3-thiazol-2-yl)]-2-(4-methyl-3-phenyl(1,3-thiazolin-2-ylidene))ethanenitrile, 2-(5-acetyl-4-methyl-3-phenyl(1,3-thiazolin-2-ylidene))-2-[4-(2,3-dimethyl-5-oxo-1-phenyl(3-pyrazolin-4-yl))(1,3-thiazol-2-yl)]ethanenitrile, and ethyl 2-(cyano(4-(2,3-dihydro-1,5-dimethyl-3-oxo-2-phenyl-1H-pyrazol-4-yl)thiazol-2-yl)methylene)-2,3-dihydro-4-methyl-3-phenylthiazole-5-carboxylate were synthesized by treatment of 2-(4-(2,3-dihydro-1,5-dimethyl-3-oxo-2-phenyl-1H-pyrazol-4-yl)thiazol-2-yl)-3-mercapto-3-(phenylamino)-acrylonitrile with appropriate halo ketones or halo esters. Also, 4-{2-[5,7-dimethyl-2-(phenylamino)(7a-hydropyrazolo[1,5-a]pyrimidin-3-yl](1,-thiazol-4-yl)}-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one derivatives were synthesized via reaction of 4-{2-[5-amino-3-(phenylamino)pyrazolin-4-yl](1,3-thiazol-2-yl)}-2,3-dimethyl-1-phenyl-3-pyrazolin-5-one with β-diketone or β-keto ester. All synthesized compound were established by elemental analysis, spectral data, and alternative synthesis whenever possible.     

A simple and convenient synthesis of 3-[5-(trifluoromethyl)-1,2,3-triazol-4-yl]cinnamic acids from 4-aryl-6-(trifluoromethyl)-2H-pyran-2-ones and sodium azide

4-Aryl-6-(trifluoromethyl)-2H-pyran-2-ones and ethyl 4-aryl-6-(trifluoromethyl)-2-oxo-2H-pyran-3-carboxylates react with sodium azide to produce highly functionalized CF₃-1,2,3-triazoles: 3-[5-(trifluoromethyl)-1,2,3-triazol-4-yl]cinnamic acids and monoethyl esters of [5-(trifluoromethyl)-1,2,3-triazol-4-yl]arylmethylidene malonic acids.     

A supramolecular assembly of side-by-side polyimidazole tripod coils stabilized by pi-pi stacking and unique boric acid templated hydrogen bonding interactions

The self assembly of (bis(1-methyl-imidazol-2-yl)methyl)(1-methyl-4-nitroimidazol-2-yl)methyl)amine and boric acid results in a supramolecular structure containing bundled antiparallel imidazole-boric acid helices and boric acid filled one-dimensional channels.     

Synthesis of methyl esters of 5-amino-4-(substituted amino)-2-methylthio-7H-pyrrolo[2,3d]-pyrimidine-6-carboxylic acids

The optimum route for the synthesis of methyl esters of N-[(4-substituted amino)-5-cyano-2-methylthiopyrimidin-6-yl]amino acids (which are starting materials for preparing the methyl esters of the corresponding 5-amino-4-(substituted amino)pyrrolo[2,3-d]pyrimidine-6-carboxylic acids) is via subsequent reactions of 4,6-dichloro-2-methylthiopyrimidine-5-carbonitrile with amines and methyl glycinate. In some examples, the reaction of methyl N-(4-chloro-2-methylthio-6-pyrimidinyl)aminoacetate with amines occurs to give the corresponding acid amides. The previously unknown synthesized derivatives of pyrimidin-6-yl amino acids and 4,5-diaminopyrrolo[2,3-d]pyrimidine- 6-carboxylic acids possess fungicidal properties.Vilnius University, Vilnius 2006, Lithuania. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No 7, pp. 955–961, July, 2000.     

Formation of ω-(4-oxo-1,4-dihydropyridin-2-yl)alkanamides in the Beckmann rearrangement of spiro-fused cycloalkanone oximes

ω-(4-Oxo-1,4-dihydropyridin-2-yl)alkanamides were obtained from cycloalkanone oximes spirofused to 4-oxo-6-methyl-1,2,3,4-tetrahydropyridine fragment through the α-carbon atom and C², respectively, on heating in polyphosphoric acid. The resulting amides were converted to the corresponding acids and methyl esters. Methylation of 5-(6-methyl-4-oxo-1,4-dihydropyridin-2-yl)pentanamide with diazomethane gave 4-methoxypyridine derivative as the major product and a small amount of N-methyl derivative, 5-(1,6-di-methyl- 4-oxo-1,4-dihydropyridin-2-yl)pentanamide.     

Chinazolincarbonsäuren. VII. Mitteilung. Ein einfacher Zugang zu (4-Oxo-3,4-dihydrochinazolin-3-yl)-alkansäuren, (4-Oxo-3,4-dihydro-1,2,3-benzotriazin-3-yl)-alkansäuren und deren Estern

Quinazoline Carboxylic Acids. An Easy Route to (4-Oxo-3,4-dihydroquinazolin-3-yl)-alkanoic Acids, (4-Oxo-3,4-dihydro-1,2,3-benzotriazin-3-yl)-alkanoic Acids and their Esters A new route was found for the synthesis of (4-Oxo-3,4-dihydroquinazolin-3-yl)-alkanoic acids ( 8 ) and (4-Oxo-3,4-dihydro-1,2,3-benzotriazin-3-yl)-alkanoic acids ( 6 ) by cyclization of the N-(2-aminobenzoyl)amino acids 5 with HCOOH or HNO₂. 2H-3,1-Benzoxazine-2,4(1H)-diones ( 1 ) reacted with glycine esters to 2 , which were cyclized by HNO₂ to the esters 4 . Ester 4 was hydrolyzed to 6 (X = CH₂). Diones 1 reacted with the most common amino acids (as the ammonium salt of tertiary amine) to amino-alkanoic acids 5 , which were cyclized with orthoformate to 7 or 8 depending on the reaction conditions.     

Synthesis of trifluoromethyl derivatives of alkyl 2-nitromethylphosphonopropionates and -phosphonobutyrates

By adding diethyl hydrogen phosphite to 5-trifluoromethyl-2-furaldehyde (5-trifluoromethylfur-2-yl)(diethoxyphosphoryl)methanol was synthesized. It was oxidized with DMSO-acetic anhydride mixture to diethyl 5-trifluoromethyl-2-furoyl phosphonate. The reaction of the latter with ethoxymethylenetriphenylphosphorane gives ethyl (2E)-3-(diethoxyphosphoryl)-3-(5-trifluoromethylfur-2-yl)propenoate. Analogous reaction of (diethoxyphosphoryl)(5-trifluoromethylfur-2-yl)acetic aldehyde yields ethyl (4E)-4-(diethoxyphosphoryl)-4-(5-trifluoromethylfur-2-yl)-but-3-enoate. The addition of nitromethane to these esters of unsaturated acids in the presence of potassium fluoride gives a mixture of diastereomers of phosphorylated esters of 2-nitromethyl-3-(5-trifluoromethylfur-2-yl)propanoic and 3-nitromethyl-4-(5-trifluoromethylfur-2-yl)butanoic acids respectively. By the reduction of ethyl nitropropanoate with zinc and formic acid in dioxane ethyl 2-aminomethyl-3-(diethoxyphosphoryl)-3-(5-trifluoromethylfur-2-yl)propanoate was prepared in a low yield. It may be considered as the derivative of β-alanine containing additional pharmacophore fragments.     

Functionalization of 6-nitrobenzo[1,3]dioxole with carbonyl compounds via TDAE methodology

We report herein the synthesis of substituted 2-(6-nitrobenzo[1,3]dioxol-5-yl)-1- aryl ethanols and 2-(6-nitrobenzo[1,3]dioxol-5-yl)-propionic acid ethyl esters from the reaction of 5-chloromethyl-6-nitrobenzo[1,3]dioxole with various aromatic carbonyl and alpha- carbonyl ester derivatives using the tetrakis(dimethylamino)ethylene (TDAE) methodology.     

Crystal structure of 6-[(1-methyl-4-nitroimidazol-5-yl)thio] purine

6-[(l-methyl-4-nitroimidazol-5-yl)thio] purine, is an immunosuppressant derivative of the antitumour drug, 6-mercaptopurine. Crystals are monoclinic witha = 4.488(2),b = 31.886(4), c = 8.067(2)A and β= 105.99(2)° in the space group P2₁/c. The crystal structure was solved by direct methods using diffractometer data and refined by least squares to anR- index of 0.065 for 502 observed reflections. The molecule crystallizes in the N(9)-H tautomer form, in contrast to the N(7)-H tautomer form found in crystals of 6-mercaptopurine and assume a conformation in which the substituents on the sulphur atom are directed away from imidazole moiety of the purine NCL Communication number 3313     

Synthesis of 2-Substituted 7-Methyl-6-(nitroimidazolyl)thiopurines

2-Substituted 7-methyl-6-(nitroimidazolyl)thiopurines have been synthesized by the reaction of 2-chloro(phenylamino, cycloalkylamino)-7-methyl-6-thiopurines with 5(4)-halo-4(5)-nitroimidazoles and the reaction of 2,6-dichloro-(6-chloro-2-dimethylamino)-7-methylpurines with sodium or ammonium salts of 5(4)-mercapto-4(5)-nitroimidazoles.     

Fused s-triazino heterocycles. V. 1,3,4,6,9b-Pentaazaphenalenes. Reactions of a carboxylic acid side chain

Procedures were developed to convert 4-(2-methyl-1,3,4,6,9b-pentaazaphenalene-5-yl)butanoic acid (Ia) and 3-(2-methyl-1,3,4,6,9b-pentaazaphenalene-5-yl)propanoic acid (IIa) to a series of esters and amides.     

Reaction of Long-Chain Vanillyl Esters with CH-Acids and 2-Naphthylamine

The previously unknown 4-(alkyl-11-oxo-7,8,9,10,11,12-hexahydrobenzo[a]acridin-12-yl)- and 4-(alkyl-1,8-dioxo-2,3,4,5,6,7,8,9-octahydro-1H-xanthen-9-yl)-2-methoxyphenyl esters of aliphatic (C₅-C₇, C₁₂) carboxylic acids were synthesized via cascade heterocyclization of cyclohexane-1,3-dione and dimedone with 2-naphthylamine and long-chain vanillyl esters.     

Synthesis and transformations of derivatives of 2-aryl-5-(3,5-dimethyl-1H-pyrazol-1-yl)-1,3-oxazole-4-carboxylic acid

On the basis of methyl esters of 2-aryl-5-hydrazino-1,3-oxazole-4-carboxylic acids the earlier unknown methyl esters of 2-aryl-5-(3,5-dimethyl-1H-pyrazol-1-yl)-1,3-oxazole-4-carboxylic acids as well as their functional derivatives were synthesized. The latter were used for further transformations, in particular, for introducing the residues of highly basic aliphatic amines into the 5 position of oxazole, and the oxazol-2-yl moiety into the 4 position of the oxazole ring.     

Electroreductive five- and six-membered cyclization of aromatic β- and γ-imino esters derived from (S)-aspartic acid and (S)-glutamic acid

The electroreduction of aromatic β-dimethylcarbamoyl-β-imino esters, prepared from (S)-aspartic acid, in the presence of chlorotrimethylsilane gave five-membered cyclized products, 1-benzoyl-4-hydroxy-5-aryl-N,N-dimethylpyrrolidine-2-carboxamides and 5-(dimethylcarbamoyl)-2-aryl-1H-pyrrol-3-yl benzoates, depending on the post-treatment after the electroreduction. The electroreduction of aromatic γ-dialkylcarbamoyl-γ-imino and γ-methoxylmethyl-γ-imino esters, prepared from (S)-glutamic acid, and following transformation gave six-membered cyclized products, 1-benzoyl-5-hydroxy-N,N-dialkyl-6-phenylpiperidine-2-carboxamides and 3-hydroxy-6-(methoxymethyl)-2-phenylpiperidin-1-yl)(phenyl)methanones, respectively.     

Studies on penem and carbapenem. I. Syntheses and oral absorption of ester-type prodrugs of sodium (5R,6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3-c arboxylat e

Acyloxyalkyl esters (2a-d), alkyloxycarbonyloxyalkyl esters (2e-g) and (5-methyl-2-oxo-1,3-dioxol-4-yl)methyl ester (2h) of (5R,6S)-2-(2-fluoroethylthio)-6-[(1R)-1-hydroxyethyl]penem-3- carboxylic acid (1) were synthesized. Enhanced oral absorption was observed in mice reflecting increased lipophilicity, compared with the parent 1 itself. Among them, the ester 2h showed a prolonged plasma level and a large area under the blood concentration-time curve (AUC) in rats. These ester-type prodrugs of penem 1 in phosphate buffer (pH 6.86) were much more stable than those of cephalosporins which easily degraded via isomerization to delta 2 cephalosporins.     

Vanillin Esters of Aliphatic Acids in the Synthesis of 4,7-Phenanthroline Derivatives

Condensation of vanillin esters of aliphatic acids with 6-aminoquinoline and cyclic c-diketones (1,3-cyclohexanedione and dimedone) afforded new 2-methoxy-4-(11-oxo-7,8,9,10,11,12-hexahydrobenzo[b][4,7]phenanthrolin-12-yl)phenyl esters of carboxylic acids.     

α-Thioureidoalkylation of functionally substituted ureas: I. Tandem cyclization and esterification in reactions of <Emphasis Type="Italic">N</Emphasis>-(carboxyalkyl)ureas with 1,3-dialkyl-4,5-dihydroxy-4,5-diphenylimidazolidine-2-thiones in alcohols

Acid-catalyzed reactions of N-(carboxyalkyl)ureas with 1,3-dialkyl-4,5-dihydroxy-4,5-diphenylimidazolidine-2-thiones in methanol or propan-2-ol led to the formation of previously unknown ω-(4,6-dialkyl-2-oxo-3a,6a-diphenyl-5-thioxooctahydroimidazo[4,5-d]imidazol-1-yl)alkanoic acids and their methyl and isopropyl esters. The structure of some esters was proved by X-ray analysis. Methyl (4,6-diethyl-2-oxo-3a,6adiphenyl-5-thioxooctahydroimidazo[4,5-d]imidazol-1-yl)acetate showed anxiolytic effect.     

Synthesis and oral activity of pivaloyloxymethyl 7-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]-3(Z)- (4-methylthiazol-5-yl)vinyl-3-cephem-4-carboxylate (ME1207) and its related compound.

7-[2-(2-Aminothiazol-4-yl)-2(Z)-methoxyiminoacetamido]-3(Z)- (4-methylthiazol-5-yl)vinyl-3-cephem-4-carboxylic acid (11, ME1206) and its 3-trans isomer (13) were prepared to test antibacterial activity. These compounds exhibited excellent antibacterial activity against both gram-positive and gram-negative bacteria, including beta-lactamase producing strains. The pivaloyloxymethyl esters (12 and 14) of the compounds (11 and 13) were prepared by esterification with pivaloyloxymethyl iodide. Among them, pivaloyloxymethyl 7-[(Z)-2-(2-aminothiazol-4-yl)-2-methoxyiminoacetamido]- 3(Z)-(4-methylthiazol-5-yl)vinyl-3-cephem-4-carboxylate (12, ME1207) showed good urinary recovery after oral administration in mice.     

Synthesis of 5-amino-1,3-dimethylpyrazol-4-yl aryl ketones

A convenient preparation of 5-amino-1,3-dialkylpyrazol-4-yl heterocyclic ketones is reported. They are prepared from the reaction of heterocyclic esters with the di-lithio derivative from N-(4-bromo-1,3-dimethyl-1H-pyrazol-5-yl)benzamide ( 1 ).     

Synthesis of 2-amino-6-(nitroimidazolyl)thiopurines

We have synthesized a series of novel 2-amino-6-(nitroimidazolyl)thiopurines by reaction of thioguanine with 1-alkyl(1,2-dialkyl)-5-chloro-4-nitro-, 2-alkyl(1,2-dialkyl)-5-bromo-4-nitro-, and 1-alkyl(1,2-dialkyl)-4-chloro-5-nitroimidazoles.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 221–224, February, 2000.