Synthesis of 2-amino-5,5-dialkyl-4-arylmethylidene-2-oxazolines from 2-alkyl-4-arylbut-3-yn-2-ols and guanidine

Reaction between 2-alkyl-4-arylbut-3-yn-2-ols and guanidine in refluxing pyridine affords 2-amino-5,5-dialkyl-4-arylmethylidene-2-oxazolines.     

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.     

U and Pu separation with U/TEVA resin: Influence of some parameters on chromatographic cycle performances

Journal of Radioanalytical and Nuclear Chemistry - Due to unexpected Pu behavior using the U/TEVA resin and the most-recognized reagents, some key separation stages need to be studied for the...     

Unexpected formation of dinaphthoaza-17-crown-5 ether containing γ-aminopiperidine subunit

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Chlorotrimethylsilane-promoted synthesis of 1,2,4-triazolopyrimidines from 3,5-diamino-1,2,4-triazoles and pentane-2,4-diones

An efficient synthesis of 2-amino-1-R-[1,2,4]triazolo[1,5-a]- pyrimidinium or 3-amino-2-R-[1,2,4]triazolo[4,3-a]pyrimidi- nium chloride derivatives by heterocyclization of 3,5-diamino- 1-R-1,2,4-triazoles (R = Alk or Ar) with pentane-2,4-diones was developed. The process is promoted by chlorotrimethyl- silane which plays the dual role of carbonyl-activating agent and water scavenger.     

Finitely presented monoids with linear Dehn function need not have regular cross-sections

This paper shows that a finitely presented monoid with linear Dehn function need not have a regular cross-section, strengthening the previously-known result that such a monoid need not be presented by a finite complete string rewriting system, and contrasting with the fact that finitely presented groups with linear Dehn function always have regular cross-sections.