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Acyl Derivatives (acyl + derivative)
Selected AbstractsSynthesis and Antiinflammatory Activity of New Acyl Derivatives of BetulinCHEMINFORM, Issue 4 2003O. B. Flekhter Abstract For Abstract see ChemInform Abstract in Full Text. [source] Quorum-sensing in Gram-negative bacteriaFEMS MICROBIOLOGY REVIEWS, Issue 4 2001Neil A Whitehead Abstract It has become increasingly and widely recognised that bacteria do not exist as solitary cells, but are colonial organisms that exploit elaborate systems of intercellular communication to facilitate their adaptation to changing environmental conditions. The languages by which bacteria communicate take the form of chemical signals, excreted from the cells, which can elicit profound physiological changes. Many types of signalling molecules, which regulate diverse phenotypes across distant genera, have been described. The most common signalling molecules found in Gram-negative bacteria are N -acyl derivatives of homoserine lactone (acyl HSLs). Modulation of the physiological processes controlled by acyl HSLs (and, indeed, many of the non-acyl HSL-mediated systems) occurs in a cell density- and growth phase-dependent manner. Therefore, the term ,quorum-sensing' has been coined to describe this ability of bacteria to monitor cell density before expressing a phenotype. In this paper, we review the current state of research concerning acyl HSL-mediated quorum-sensing. We also describe two non-acyl HSL-based systems utilised by the phytopathogens Ralstonia solanacearum and Xanthomonas campestris. [source] Novel Chemical Transformations of TenoxicamHELVETICA CHIMICA ACTA, Issue 8 2005Kristóf Kóczián Both N - and O -substituted derivatives of the anti-inflammatory drug tenoxicam (=,4-hydroxy-2-methyl- N -(pyridin-2-yl)-2H -thieno[2,3 -e],[1,2]thiazine-3-carboxamide 1,1-dioxide; 1) were synthesized, and various chemical transformations were investigated. Both selective hydrolysis and reaction of 1,- N -methyltenoxicam (5) with a variety of N-nucleophiles were performed (Scheme,1). Also, five new 4- O -acyl derivatives 10 were prepared as potential prodrugs (Scheme,2). The 4-chloro derivatives of 1 and its analog 8 could be successfully transformed into the novel tetra- and tricyclic ring systems 12 and 13, respectively, the latter being a conformationally restricted 1,5-diaryl-pyrazole designed as a potential COX-2 inhibitor. [source] Estimating the lipophilicity of a number of 2-amino-1-cyclohexanol derivatives exhibiting anticonvulsant activity ,BIOMEDICAL CHROMATOGRAPHY, Issue 5 2009bieta P Abstract The lipophilicity of a number of N -acyl derivatives of trans - or cis -: racemic, (1R,2R)- or (1S,2S)-aminocyclohexanol (1,13) exhibiting anticonvulsant activity was investigated. Their lipophilicity (Rm0) was determined using reversed-phase thin-layer chromatography (RP-TLC) with mixtures of methanol and water as mobile phases. The partition coefficients of compounds 1,13 (log P) were also calculated using two computer programs (Pallas and Chem DU) and compared with Rm0. Copyright © 2009 John Wiley & Sons, Ltd. [source] | ||||||||||