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Mesoionic Compound (mesoionic + compound)
Selected AbstractsMultinuclear magnetic resonance study of chiral mesoionic oxa- and thiatriazole and tetrazole derivatives: adducts with dirhodium complexes and chiral recognition,MAGNETIC RESONANCE IN CHEMISTRY, Issue 5 2003Jaroslaw Ja Abstract Mesoionic compounds 1,8 were synthesized and their 1H, 13C, 14N, 15N and 17O NMR spectra recorded in the absence and presence of the chiral dirhodium complex Rh*. It is shown that the enantiomers of the mesoionic compounds could be differentiated satisfactorily (,dirhodium method'). Copyright © 2003 John Wiley & Sons, Ltd. [source] Effects of a new 1,3,4-thiadiazolium mesoionic compound, MI-D, on the acute inflammatory responseDRUG DEVELOPMENT RESEARCH, Issue 4 2004Júlio C. Cardoso Abstract A new mesoionic compound, 4-phenyl-5-(4-nitro-cinnamoyl)-1,3,4-thiadiazolium-2-phenylamine (MI-D), is described along with some of its biological properties. Its effects on hepatic metabolism, on O and nitric oxide (NO) production, and in in vivo models for potential antinociceptive, antipyretic, and antiinflammatory activities were determined. In perfused rat liver, MI-D (25 µM) stimulated glycogenolysis (95%), and inhibited oxygen uptake (37%) with affecting glycolysis. In phorbol 12-myristate 13-acetate-stimulated macrophages, O generation was reduced (95%) by MI-D (15 µM), whereas the production of NO was unaffected. MI-D (2 mg/kg) inhibited (55%) the number of abdominal writhings induced by acetic acid. At 1 mg/kg, MI-D inhibited the febrile response (5 h) induced by lipopolysaccharide (LPS) and was also effective against a preexisting febrile response. Treatment with MI-D (1 mg/kg) reduced by 67% prostaglandin (PGE2) levels in the cerebrospinal fluid of LPS-exposed mice, and at a higher dose (8 mg/kg) MI-D inhibited paw edema formation (2 h) induced by carrageenan. MI-D has a spectrum of activities similar to other nonsteroidal antiinflammatory drugs, qualifying it as a potential anti-inflammatory drug. Drug Dev. Res. 61:207,217, 2004. © 2004 Wiley-Liss, Inc. [source] Metabolism of the mesoionic compound (MI-D) by mouse liver microsome, detection of its metabolite In Vivo, and acute toxicity in miceJOURNAL OF BIOCHEMICAL AND MOLECULAR TOXICOLOGY, Issue 6 2009Silvia Romăo Abstract The mesoionic derivative 4-phenyl-5-[4-nitrocinnamoyl]-1,3,4-thiadiazolyl-2-phenylamine chloride (MI-D) has antitumoral and anti-inflammatory effects. In this study, we present aspects of its metabolism and toxicity in mice. MI-D was metabolized in vitro by liver microsome, generating a main product with a much shorter retention time than MI-D in high-performance liquid chromatography (HPLC) analysis but with a spectrum similar to that of the original molecule. Mass spectrometry with electrospray ionization in positive mode analysis of the purified compound by HPLC indicated that the product of metabolism has four additional hydroxyl groups (m/z = 465) compared with MI-D (m/z = 401). The HPLC analyses of plasma and urine samples from mice treated with MI-D showed the presence of the metabolite product. The kinetic parameters Km (19.5 ± 4.5 ,M) and Vmax [1.5 ± 0.4 units of fluorescence/(100 ,g of microsomal protein/mL/s)] were estimated, confirming the metabolism of MI-D and indicating that the reaction follows Michaelis-Menten kinetics. Acute toxicity was established on the basis of an estimation of mean lethal dose (LD-50; 181.2 mg/kg) and histopathological analysis of animals that survived the LD-50 test. Abdominal adhesions, inflammatory foci, and formation of granulomas were observed. Altogether, the results contribute to the advancement of research in support of MI-D as a future chemotherapeutic drug. © 2009 Wiley Periodicals, Inc. J Biochem Mol Toxicol 23:394,405, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20303 [source] Interference of MI-D, a new mesoionic compound, on artificial and native membranesCELL BIOCHEMISTRY AND FUNCTION, Issue 1 2002Silvia M.S.C. Cadena Abstract MI-D (4-phenyl-5-(4-nitrocinnamoyl)-1,3,4-thiadiazolium-2-phenylamine chloride), a new mesoionic compound, decreased the rate of swelling induced by valinomycin-K+, as well as induced swelling in the presence of nigericin-K+. Shrinkage was also affected, suggesting interference with the inner mitochondrial membrane, which would affect both fluidity and elasticity. Fluorescence polarization of DPH and DPH-PA, probing the core and outer regions respectively, of the DMPC and native membranes, indicated that MI-D shifts the midpoint of phase transition to higher values and orders of the fluid phase. These alterations in membrane fluidity are thus related to MI-D effects on the energy-linked functions of mitochondria. Copyright © 2001 John Wiley & Sons, Ltd. [source] Non-Dipolar Behavior of Mesoionic Heterocycles: Synthesis and Tautomerism of 2-AlkylthioisomünchnonesEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 13 2004Martín Ávalos Abstract This paper describes a general preparation of a series of 1,3-thiazolium-4-olates, each bearing an alkyl group at C-2, through reactions between N -arylthiocarboxamides and ,-haloacyl halides. Unlike the 2-aryl-substituted derivatives, such alkylated mesoionic compounds exist in equilibria with their non-dipolar tautomers, the corresponding 2-alkylidene-1,3-thiazolidin-4-ones. The unambiguous characterization of such tautomers and their relative stabilities have now been assessed by spectroscopic and computational studies. The presence of o,o, -disubstituted aryl groups at N-3 of the heterocyclic ring slows down free rotation around the N,Ar bond, thus opening access to a promising class of non-biaryl atropisomers. Finally, treatment of N -arylthioformamides with ,-haloacyl halides gives rise to N -acylthioformamides instead of the corresponding mesoionic species. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004) [source] Multinuclear magnetic resonance study of chiral mesoionic oxa- and thiatriazole and tetrazole derivatives: adducts with dirhodium complexes and chiral recognition,MAGNETIC RESONANCE IN CHEMISTRY, Issue 5 2003Jaroslaw Ja Abstract Mesoionic compounds 1,8 were synthesized and their 1H, 13C, 14N, 15N and 17O NMR spectra recorded in the absence and presence of the chiral dirhodium complex Rh*. It is shown that the enantiomers of the mesoionic compounds could be differentiated satisfactorily (,dirhodium method'). Copyright © 2003 John Wiley & Sons, Ltd. [source] | ||||||||||