Search results for "Azoles"

Leflunomide, a reversible inhibitor of pyrimidine biosynthesis?

1995

Synthesis and characterization of a series of alkyl-oxadiazolylpyridinium salts as perspective ionic liquids

2007

The synthesis of a series of 1,2,4-oxadiazolyl-N-methylpyridinium salts differing in the length and the position of the alkyl chain in the heterocyclic ring and the counter ions is reported. Some features of this new family of salts as perspective ionic liquids are described and the influence of the varying moieties in the modulation of the properties is discussed.

The Reactivity of 4’-Substituted Spiro[Isoindole-1,3’-pyrazoles] Derivatives: Substitution/Elimination Reactions and Access to Biaryl Derivatives

2017

This paper describes aspects of the chemistry of 4’-substituted spiro [indole-1,3’-pyrazoles]. These compounds underwent substitution and/or elimination reactions to afford some new spiro- as well as biaryl derivatives of potential pharmaceutical relevance. Mechanistic considerations are discussed as well.

Dehydration of detomidine hydrochloride monohydrate

2010

The thermodynamic stability of detomidine hydrochloride monohydrate has been evaluated on the basis of phase transition kinetics in solid state. A method free of empirical models was used for the treatment of kinetic data, and compared to several known solid state kinetic data processing methods. Phase transitions were monitored by powder X-ray diffraction (PXRD) and thermal analysis. Full PXRD profiles were used for determining the phase content instead of single reflex intensity measurements, in order to minimize the influence of particle texture. We compared the applicability of isothermal and nonisothermal methods to our investigation of detomidine hydrochlorine monohydrate dehydration.

Selective electrochemical discrimination between dopamine and phenethylamine-derived psychotropic drugs using electrodes modified with an acyclic rec…

2010

Electrochemical discrimination between dopamine and psychotropic drugs which have in common a skeletal structure of phenethylamine, can be obtained using acyclic receptors L(1) and L(2), containing two terminal 3-alkoxy-5-nitroindazole rings. Upon attachment to graphite electrodes, L(1) and L(2) exhibit a well-defined, essentially reversible solid state electrochemistry in contact with aqueous media, based on electrolyte-assisted reduction processes involving successive cation and anion insertion/binding. As a result, a distinctive, essentially Nernstian electrochemical response is obtained for phenethylammonium ions of methamphetamine (METH), p-methoxyamphetamine (PMA), amphetamine (AMPH),…

Optimization of anti-proliferative activity using a screening approach with a series of bis-heterocyclic G-quadruplex ligands

2013

Abstract Using a phenotypic screening and SAR optimization approach, a phenyl-bis-oxazole derivative has been identified with anti-proliferative activity, optimized with the use of a panel of cancer cell lines. The lead compound was synthesized by means of a short and effective two-step synthesis using Pd-catalyzed direct arylation. The compound stabilizes several quadruplex DNA sequences including a human telomeric DNA and one from the promoter of the HSP90 gene, although the structure–activity relationships of the series are not obviously related to the quadruplex binding.

Synthesis of ortho-fonctionnalized arylphosphines and their applications

2020

This thesis reports with the synthesis of ortho-functionnalized phosphines bearing phosphonium and 1,2,3-triazole moieties.The synthesis of phosphines-phosphoniums, using as key-step Phospha-Fries rearrangement and Appel reaction is described. Eight new phosphines- phosphoniums, bearing aryl, alkyl or ferrocenyl fragments on the phosphonium part, have been prepared with overall yields reaching 48%. These phosphines- phosphoniums have been used in the preparation of gold (I) complexes which have been characterized using spectroscopic methods and X ray diffraction. Both gold (I) complexes and phosphines-phosphoniums have been studied in biology and these compounds turned out to be cytotoxic i…

Photochemistry of 1,2,4-oxadiazoles. A DFT study on photoinduced competitive rearrangements of 3-amino- and 3-N-methylamino-5-perfluoroalkyl-1,2,4-ox…

2006

The photoinduced competitive rearrangements of 5-perfluoroalkyl-3-amino(N-alkylamino)-1,2,4-oxadia- zoles have been investigated by DFT calculations and UV-vis spectroscopy. The observed product selectivity depends on the number of hydrogen atoms present in the amino moiety and involves two or three possible routes: (i) ring contraction-ring expansion (RCRE), (ii) internal-cyclization isomerization (ICI), or (iii) C(3)-N(2) migration-nucleophilic attack-cyclization (MNAC). UV absorption and fluorescence spectra of the reactants, and vertical excitation energy values, calculated by time dependent DFT, support the involvement of a neutral singlet excited state in the photoexcitation process. …

Effects of carboxyamidotriazole on in vitro models of imatinib-resistant chronic myeloid leukemia.

2008

Although imatinib mesylate (IM) has revolutionized the treatment of chronic myeloid leukemia (CML), some patients develop resistance with progression of leukemia. Alternative or additional targeting of signaling pathways deregulated in bcr-abl-driven CML cells may provide a feasible option for improving clinical response and overcoming resistance. In this study, we show that carboxyamidotriazole (CAI), an orally bioavailable calcium influx and signal transduction inhibitor, is equally effective in inhibiting the proliferation and bcr-abl dependent- and independent-signaling pathways in imatinib-resistant CML cells. CAI inhibits phosphorylation of cellular proteins including STAT5 and CrkL a…

Reactive oxygen and ethylene are involved in the regulation of regurgitant-induced responses in bean plants.

2004

Summary Application of regurgitant from Leptinotarsa decemlineata Say on wound surfaces of one wounded leaf of intact bean ( Phaseolus vulgaris L.) plants resulted in activation of ethylene biosynthesis followed by an increase of both peroxidase and polyphenol oxidase activity. The aim of the present investigation was to study the source of increased oxidative enzyme activities in regurgitant-treated bean leaves and to determine if hydrogen peroxide and ethylene biosynthesis is responsible for regurgitant-induced amplification of wound responses in bean plants. As the regurgitant contained relative high activities of both peroxidase and polyphenol oxidase, there is a possibility that increa…