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Acylation of tert-butyl 3-(methylamino)but-2-enoate with fluorinated acetic acid anhydrides occurred at the enamine carbon atom. The reaction of the resulting tert-butyl 3-(methylamino)-2-(RFCO)but-2-enoates with alkyl hydrazines resulted in mixtures of isomeric pyrazoles that were easily separated by column chromatography. The target fluorinated pyrazole-4-carboxylic acids were obtained on a multigram scale. [ABSTRACT FROM AUTHOR]

Two isomeric conformationally restricted analogues of 4-trifluoromethylpiperidine were designed. The synthesis was performed in four steps from commercially available N-benzylmaleimide. The key reaction was the [3+2] cycloaddition between trifluoromethyldiazomethane and N-benzylmaleimide. [ABSTRACT FROM AUTHOR]

An improved synthesis of 2-, 3-, and 4-trifluoromethylcyclohexylamines on a multigram scale via PtO2-mediated hydrogenation of the corresponding trifluoromethylanilines in trifluoroacetic acid at room temperature under atmospheric pressure is reported. The hydrogenation occurred with a remarkable stereoselectivity favoring the formation of cis-isomers. [ABSTRACT FROM AUTHOR]

Thiacalix[4]arenes bearing one, three, or four P=O containing groups at the upper or at the lower rim have been synthesized. Stereochemistry of the compounds was investigated by X-ray method. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis of proline analogues bearing a fluorine-containing substituent at the fifth position of the pyrrolidine ring, racemic trans- and cis-5-fluoromethyl prolines, was performed. The key step of the synthesis is a transformation of the CH2OH-group into the CH2F-one using morpholinosulfur trifluoride. During the synthesis, an efficient procedure to prepare trans- and cis-5-fluoropipecolic acids was elaborated. [Copyright &y& Elsevier]

Abstract: The introduction of a hydrazine functionality into 2-(2-cyanovinyl)-3-oxo-cyclohex-1-ene enolates results in their spontaneous cyclizations with participation of the hydrazine moiety. Depending on the reaction conditions used, the hydrazine-derived enolates are transformed into derivatives of 1-arylpyridine-2-one-3-carbonitriles or pyrazoloquinolinones in a one-pot synthesis. They also react with anilines to give the corresponding N1-substituted pyridine-2-one-3-carboxamides. Product characterization was performed by means of spectroscopic and X-ray diffraction studies. In addition, for structure elucidation purposes, a counter synthesis of 1-arylaminopyridine-2-one-3-carboxamide was also carried out. [Copyright &y& Elsevier]

Abstract: Reaction of 4-hydrazinoquinazoline with 2,4-diketoesters gives the corresponding 3-acylmethyl-2H-[1,2,4]triazino[2,3-c]quinazolin-2-ones in a one-step procedure via cyclocondensation–Dimroth-like rearrangement. Spectroscopic studies as well as X-ray analysis reveal that the obtained triazinoquinazolines exist in their ketoimine tautomeric form. Treatment of these compounds with hydrazine hydrate affords 3′-(2-aminophenyl)-3-(het)aryl-spiro[pyrazoline-5,6′(1′H)-1,2,4-triazin]-5′(4′H)-ones or 5-(het)arylpyrazole-3-carboxylic acid hydrazides depending on the reaction conditions. The structure of the spiro-heterocycles was elucidated by means of single-crystal X-ray analysis and confirmed by spectroscopic investigations. [Copyright &y& Elsevier]

Abstract: 2- and 3-Trifluoromethylmorpholines were prepared in racemic and optically active forms. The synthesis commenced from the commercially available 2-trifluoromethyloxirane. The elaborated procedures were scalable, and the products were obtained in multigram quantities. The obtained compounds were comprehensively characterized by crystallographic analysis, fluorescence measurements, solubility, pK a, logD parameters, and clearance rate. The potential of the synthesized amines as the building blocks for drug discovery is thus demonstrated. [Copyright &y& Elsevier]

Abstract: A convenient synthesis of isothiochromen-4-one 2,2-dioxide was carried out via cyclisation of o-cyanobenzyl thioacetate by a Thorpe reaction. The reactions of isothiochromen-4-one 2,2-dioxide with nitrogen-containing nucleophilic reagents have been investigated. [Copyright &y& Elsevier]

Abstract: Sulfonylamidophosphates with formula PhSO2NHP(O)(OR)2 (HL1: R=PhCH2 ld>L2: R= p-MeC6H4 e:italic>p-C6H4SO2NHP(O)(OMe)2)2 (H2 L3) were synthesized via a three-step procedure based on Kirsanov reaction. Sodium salts NaL1, NaL2 and Na2 L3 were prepared from the corresponding sulfonylamidophosphates to explore their acid nature of the imide nitrogen. The products were characterized by means of 1H, 31P NMR and IR spectroscopies and elemental analysis. Crystal structures of HL2, H2 L3 and NaL2 were determined using X-ray crystallography. HL2 produces a dimeric aggregate via intermolecular hydrogen bonding. In contrast, H2 L3 and NaL2 form 1D polymeric chains. [Copyright &y& Elsevier]

Abstract: Heating of N-{2-[(R-amino)carbonyl]phenyl}prolinamides in triethyl orthoformate solution was found to give 6-R-5,6,6a,8,9,10,10a,11-octahydropyrrolo[1′,2′:3,4]imidazo[1,2-a]quinazoline-5,11-diones. Similar reaction of N-{2-[(R-amino)carbonyl]phenyl}thiazolidine-4-carboxamides afforded 6-R-5,6,6a,10,10a,11-hexahydrothiazolo[3′,4′:3,4]imidazo[1,2-a]quinazoline-5,11-diones. The relative configuration of C-6a and C-10a centres of the tetracyclic compounds obtained was assigned as trans on the basis of X-ray crystallographic study. [Copyright &y& Elsevier]

Straightforward practical synthetic approaches to 3,4-bis-and 3,4,5-tris(trifluoromethyl)pyrazoles have been developed. The key step of the both syntheses is a transformation of the carboxylic group in a pyrazole core into the trifluoromethyl group by sulfur tetrafluoride. The elaborated synthetic protocols allow gram-scale preparation of the target products. The obtained compounds are comprehensively characterized by means of crystallographic analysis, determination of pKa values and fluorescence measurements. [ABSTRACT FROM AUTHOR]

Abstract: Cup-shaped calix[4]arenes bearing one or two ketocyanine fluorophore fragments at the wide rim of the macrocycle are synthesized by condensation of formyl calix[4]arenes with arylmethylene(hetarylmethylene)cyclopentanones in the presence of the ionic liquid, dimethylammonium dimethylcarbamate (DIMCARB) and characterized using UV–vis and fluorescence spectroscopy. Strong positive solvatofluorochromism for the calixarene ketocyanines is observed. [Copyright &y& Elsevier]

Abstract: A Biginelli-like three-component condensation using 3-amino-1,2,4-triazole as urea component resulted in an unexpected alternative direction of the tetrahydropyrimidine ring formation. [Copyright &y& Elsevier]

Abstract: The reaction of 2-aminobenzamides with 2-oxocyclopentane-, 2-oxocyclohexane-, and 2-oxocycloheptaneacetic acids esters was found to give 7a,8,9,10-tetrahydrocyclopenta[2,3]pyrrolo[1,2-a]quinazoline-6,12(7H,11H)-diones, 7,7a,8,9,10,11-hexahydro-6H-indolo[1,7a-a]quinazoline-6,13(12H)-diones, and 7a,8,9,10,11,12-hexahydrocyclohepta[2,3]pyrrolo[1,2-a]quinazoline-6,14(7H,13H)-diones, respectively. The relative configuration with the cis-fused butyrolactam and cycloalkane rings was assigned to the prepared compounds on the basis of an X-ray crystallographic study. [Copyright &y& Elsevier]

Abstract: A series of new tetraazaspiro[5,5]-undec-4-ene-2,7,9,11-tetraones have been obtained by reaction of 5-(2-arylethylidene-2-oxo)-1,3-dimethylpyrimidine-2,4,6-triones with ureas. A three-component one-pot procedure to the spiranes synthesis was also developed. One-pot reaction of arylglyoxals, 1,3-dimethylbarbituric acid, and dimethylurea led to imidazolyl-1,3-dimethylbarbituric acids. Mechanisms of studied reactions were discussed. [Copyright &y& Elsevier]

Two heterometallic polymers containing cations [Cu(en)2]2+ and either the [Mn(mal)2(H2O)2]2 (1) or [Mn2(succ)2Cl2]n2n-,~~ (2) anions (mal = malonate and succ = succinate) were investigated by X-ray crystallography, high-field electron paramagnetic resonance (EPR) spectroscopy, and magnetic susceptibility measurements. Magnetic susceptibility and EPR spectra characteristic of antiferromagnetically coupled Mn2+-Mn2+ pairs were observed in 2, and the exchange integral J = 31 cm-1 (H = JS1S2) as well as the zero-field-splitting parameter D = -3.046 cm-1 in the triplet state of the dimanganese entity was determined. [ABSTRACT FROM AUTHOR]

Abstract: Calix[4]arenes bearing a methoxy and an R or S α-phenylethylacetamido group at the narrow rim of macrocycles are stereoselectively acylated with 1equiv of trichloroacetyl isocyanate to give chiral asymmetrically substituted calix[4]arenecarbamates in preparative yields and high diastereomeric excess. [Copyright &y& Elsevier]

Abstract: The stereoselective synthesis of 2-azabicyclo[2.2.1]heptane-1-carboxylic acid and 6-azabicyclo[3.2.1]octane-5-carboxylic acid, novel rigid bicyclic proline analogues, is reported. The synthesis was performed in five steps from the corresponding 2-cycloalken-1-ones. A known approach to 2,4-methanoproline is improved. The three amino acids constitute a library of conformationally constrained proline analogues, which can be used for the design of peptidomimetics and peptide models. [Copyright &y& Elsevier]

Abstract: The heterometallic complex [Co(L1)Cl2][ZnCl3(DMF)] (L1 =4,6,6-trimethyl-1,9-diamino-3,7-diazanon-3-ene) has been obtained by direct template synthesis from cobalt powder, zinc oxide, zinc chloride, ethylenediamine dihydrochloride and acetone in dimethylformamide and characterized by X-ray crystallographic analysis. The mechanism of the complex formation is suggested. [Copyright &y& Elsevier]