Alkylation of 6-Polyfluoroalkyl-2-thiouracils with Haloalkanes

Russian Journal of Organic Chemistry - The structure of 6-polyfluoroalkyl-2-thiouracils and reactivity of nucleophilic centers in their molecules were analyzed by quantum chemical calculations....     

Synthesis of New Heteroatomic Podands from Ethyl 2-[(2-Aminophenylamino)Methylidene]-3-Oxoalkanoates and Thiophene-2,5-Dicarboxaldehyde

Condensation of two moles of ethyl 2-[(2-aminophenylamino)methylidene]-3-oxo-3-(polyfluoroalkyl)propionates with 2,5-thiophene-dicarboxaldehyde results in new heteroatomic podands. X-ray data showed that in the solid state these molecules arrange in two independent chelating fragments of b-amino enone type, thiophene fragment being a spacer.     

One-pot synthesis of 5-fluoroalkyl-5-hydroxy-4-hydroxy-imino-1-isonicotinoyl-4,5-dihydro-1<Emphasis Type="Italic">H</Emphasis>-pyrazoles and their tuberculostatic activity

5-Fluoroalkyl-5-hydroxy-4-hydroxyimino-1-isonicotinoyl-4,5-dihydro-1H-pyrazoles were synthesized via a one-pot procedure from polyfluoroalkyl-containing 1,3-diketones, sodium nitrite in acetic acid, and isoniazid. Acetylacetone gave rise to 3-hydroxyiminopentane-2,4-dione monoisonicotinoylhydrazone which underwent intramolecular cyclization to 5-hydroxy-4-hydroxyimino-1-isonicotinoyl-3,5-dimethyl-4,5-dihydro-1H-pyrazole on heating in ethanol. The synthesized compounds exhibited moderate tuberculostatic activity.     

Synthesis of polyfluoroalkyl-containing 1-(4-acetoxybutyl)- and 1-(4-hydroxybutyl)pyrazoles and their tuberculostatic activity

Alkylation of polyfluoroalkyl-containing pyrazoles with 4-bromobutyl acetate in acetone in the presence of potassium carbonate leads to a mixture of isomeric 1-(4-acetoxybutyl)-3-fluoroalkyl- and 1-(4-acetoxybutyl)-5-fluoroalkylpyrazoles, which in a number of cases were successfully separated by HPLC. Deacylation in acidic medium with gaseous hydrogen chloride and in basic medium with gaseous ammonia leads to 1-(4-hydroxybutyl)pyrazoles, which manifest moderate tuberculostatic activity.     

A concise approach to CF3-containing furan-3-ones, (bis)pyrazoles from novel fluorinated building blocks based on 2,3-butanedione

1,1,1-Trifluoro-4,5,5-trimethoxyhex-3-en-2-one and lithium (2Z)-1,1,1-trifluoro-5,5-dialkoxy-4-oxohex-2-en-2-olate were synthesized for the first time via direct trifluoroacetylation of 2,3-butanedione acetal derivatives. A simple and effective approach to acetal or acyl substituted CF₃-pyrazoles, 5,5′-bis(trifluoromethyl)-3,3′-bipyrazole, and, to 5-trifluoromethylfuran-3-ones is presented.     

Reactions of 3-acetyl- and 3-acetimidoyl-5,6,7,8-tetrafluoro-4-hydroxycoumarins with substituted hydrazines

Russian Chemical Bulletin - 3-Acetyl- and 3-acetimidoyl-5,6,7,8-tetrafluoro-4-hydroxycoumarins react with methyl- and phenylhydrazines giving either condensation products at the acyl substituent,...     

Synthesis and properties of 2-azahetarylaminomethylidene 1,3-dicarbonyl compounds

Reactions of 2-ethoxymethylidene 1,3-dicarbonyl compounds with pyridine-2,6- and pyrimidine-4,5-diamines gave the corresponding 2-hetarylaminomethylidene derivatives. Depending on the initial reactant structure, the formation of mono-and/or bis-condensation products is possible. Hetarylaminomethylidene derivatives showed a moderate tuberculostatic effect. 2-Pyridinylaminomethylidene 3-oxo esters were used as ligands to obtain coordination compounds with d- and f-metal ions.     

Structure of diethyl (polyfluorobenzoyl)malonates and their thermal intramolecular cyclization

The reaction of the C-ethoxymagnesium derivative of diethyl malonate with polyfluorobenzoyl chlorides affords the corresponding (polyfluorobenzoyl)malonates prone to thermal cyclization into coumarin derivatives. The compounds obtained are inherent in keto—enol tautomerism.     

Heterocyclic dialdehydes: linkers in the synthesis of macroacyclic ligands

Macroacyclic heteroatomic podands containing one chelation cavity were obtained as a result of the biscondensation of diethyl 2-[(2-aminophenyl)aminomethylidene]malonate with heterocyclic dialdehy- des (2,5-thiophenedicarbaldehyde and 2,6-pyridinedicarbaldehyde).     

Fluorinated 2-amino-5-phenyl-1,3,4-thiadiazines: synthesis and structures

Fluorinated 2-amino-5-phenyl-1,3,4-thiadiazines were obtained for the first time. A study of their tautomeric structures revealed that trifluoromethyl-containing 1,3,4-thiadiazines exist as the 4H-tautomer in both solutions and the solid state, while their monofluoroaryl analogs exist as the 6H-tautomer.