Jozsef Reiter

On triazoles XI . structure elucidation of isomeric 1,2,4-triazolopyrimidinones

Abstract The structure of Isomeric 3 – 6 type triazolo-pyrimidinones and their N-methylated and N-benzylat-ed derivatives was elucidated. In spite of the good agreement between the carbonyl bonds of derivatives 3 – 6 (R1= CH3, R=H, Q=SCH3) and their structure the IR method did not prove to be characteristic in general for the above structures. In contrast to the results reported previously it was found that the 3 - 6 type derivatives are well characterised by their UV spectra taken in neutral solution. The 13C-NMR spectra gave an unequivocal proof of the above structures corroborating the conclusions drawn from the UV measurements.

Preparation and antiarthritic activity of new 1,5-diaryl-3-alkylthio-1H-1,2,4-triazoles and corresponding sulfoxides and sulfones

Abstract A series of 1,5-diaryl-3-alkylthio-1H-1,2,4-triazoles and corresponding sulfoxides and sulfones was synthesized and evaluated as antiinflammatory agents in the rat adjuvant induced arthritis assay. Several analogues were found to be more potent than phenylbutazone and naproxen. Structure-activity relationships are discussed.

On triazoles XIX: The reaction of 5-amino-1,2,4-triazoles with functionalized acetoacetic esters

SummaryDifferent “functionalized” alkyl 3-oxo-butyrates (2) were reacted with 5-amino-3-Q-1H-1,2,4-triazoles (1) to yield3 and4 type 1,2,4-triazolo[1,5-a]pyrimidinones. In case of2 (R1=methyl,R2=1-ethoxycarbonylethyl,R3=ethyl) beside the corresponding derivative4 the unexpected 5,6-dihydro-6,8-dimethyl-7-ethoxycarbonyl-3-methylthio-1,2,4-triazolo[4,3-a]-1,3-diazepin-5(9H)-one (7) was isolated, representing a novel ring system.ZusammenfassungVerschiedene „funktionalisierte“ 3-Oxo-buttersäurealkylester (2) wurden mit 5-Amino-3-Q-1H-1,2,4-triazolen (1) umgesetzt, wobei 1,2,4-Triazolo[1,5-a]pyrimidinone der Typen3 und4 erhalten wurden. Im Fall von2 (R1=Methyl,R2=1-Ethoxycarbonylethyl,R3=Ethyl) wurde neben dem erwarteten Derivat4 das unerwartete 5,6-Dihydro-6,8-dimethyl-7-ethoxycarbonyl-3-me-thylthio-1,2,4-triazolo[4,3-a]-1,3-diazepin-5(9H)-on (7) isoliert, welches ein neues Ringsystem darstellt.

On triazoles, IX HMO calculations of tautomeric 1,2,4-triazole derivatives

HMO calculations were performed for all possible tautomeric forms of different 1,2,4-triazole derivatives1–4 and their condensed ring analogues5–8. The resonance energies obtained showed this method useful for the differentiation of the tautomeric structure of the planar monocyclic 1,2,4-triazole derivatives but it did not give satisfactory results in case of their non-planar condensed ring analogues.ZusammenfassungDie HMO-Methode wurde für alle möglichen tautomeren Formen der 1,2,4-Triazol-Derivate1–4 und deren kondensierte Analogen5–8 verwendet. Die berechneten Resonanzenergien bewiesen, daß dieHückel-Methode gute Resultate für die Unterscheidung verschiedener tautomerer Formen der planaren 1,2,4-Triazol-Derivate, aber nicht für deren nicht-planare kondensierte Analogen ergibt.