0000000000017786
AUTHOR
Mohamed Akssira
Diterpenoids from Tetraclinis articulata that Inhibit Various Human Leukocyte Functions
Ten new compounds, eight of them pimarane derivatives (1-8), together with a menthane dimer (9) and a totarane diterpenoid (10), were isolated from the leaves and wood of Tetraclinis articulata. The structures of 1-10 were established by using spectroscopic techniques, including 2D NMR spectra. Pimaranes 1-5 were found to possess an unusual cis interannular union of the B and C rings, which, from a biogenetic perspective, could be derived from the hydration of a carbocation at C-8. Compounds 4-6 and a mixture of 7 and 11 modulated different human leukocyte functions at a concentration of 10 microM, mainly the degranulation process measured as myeloperoxidase release and, to a lesser extent,…
Chemical composition and antibacterial effect of Smyrnium olusatrum L. Fruit Essential Oil
The plants of the <em>Apiaceae</em> family are mainly used for food purposes and their multiple therapeutic properties and biological activities. This study aims to determine the chemical composition of Essential Oil (EO) of the fruits of <em>Smyrnium olusatrum</em> L. obtained by hydrodistillation in Clevenger-type apparatus. GC/MS analyzed the EO and the antibacterial activity was evaluated against clinical bacterial strains by two complementary methods (Disc diffusion and micro-atmosphere) and determination of Minimal Inhibitory Concentration (MIC). The results of chemical composition show that the EO is dominated by hydrocarbon monoterpenes (55,95%). The antibact…
A Facile Synthesis of New 3-Substituted-2,3- dihydropyrido[3,2-d]pyrimidine-2,4-diones
Abstract Pyrido[3,2-d]pyrimidine-2,4-diones derivatives have been synthesized in good yields by two efficient synthetic routes, the first one through an hetero-cyclization on the ureas derivatives 3a–e under alkaline conditions, the second one by condensation of the isocyanate 2 with various arylalkylamines in pyridine.
Synthesis and evaluation of 2-tosylamino and 2-tosyliminopyrimidine derivatives as inhibitors of some leukocyte functions
Abstract We have studied the potential anti-inflammatory effects of 20 2-tosylamino and 2-tosyliminopyrimidine new derivatives in human neutrophils. We have evaluated their interference with some leukocyte functions and 5-lipoxygenase activity. All the compounds reduced neutrophil degranulation process at concentrations in the μM range. Besides, compounds with a phenolic substitution inhibited leukotriene B 4 biosynthesis in neutrophils and decreased the cell-free 5-lipoxygenase activity. This study demonstrates that 2-tosylamino and 2-tosyliminopyrimidine derivatives can reduce the activation of neutrophil cells which may have relevance for the modulation of the inflammatory response.
Experimental and theoretical investigations for the regio and stereoselective transformation of trans 1,2,3-trisubstituted aziridines into trans oxazolidin-2-ones
The regio and stereoselective transformation of trans 1,2,3-trisubstituted aziridines into trans oxazolidin-2-ones takes place in good yield. However, the cis configuration at C2 and C3 in monocyclic aziridines is a limiting factor for this transformation. Ab initio calculations show that while the ring-opening process assisted by iodide is regioselective, the subsequent ring-closure is responsible for the retention of the configuration at the trans oxazolidin-2-ones. The larger energy found for the ring-closure process for the cis aziridines accounts for the non-formation of the cis oxazolidin-2-ones.
Efficient synthesis of novel pyrido[3,2-d]pyrimidine-2,4-diones
Abstract A series of pyrido[3,2- d ]pyrimidine-2,4-diones 5a – g have been synthesized through conversion of 2,3-pyridinedicarboxylic anhydride 1 into half-ester 2 , subsequent Curtius rearrangement and further reaction with amino acids.
In vitro antibacterial and biofilm inhibitory activity of the sawdust essential oil of Tetraclinis articulata (vahl) against catheter-associated Staphylococcus aureus clinical isolates
Abstract The aim of the present study was to determine the chemical composition, antibacterial and antibiofilm activities of the essential oil of sawdust from root burl wood of T. articulata. Nine strains including 8 clinical isolates from catheters-related infections and one ATCC 25923 were tested. Twenty-seven different compounds were identified by GC–MS in the essential oil of T. articulata extracted by hydrodistillation. Carvacrol and cedrol were the principal compounds representing 34.37 ± 0.07 and 11.07 ± 0.09 respectively. The EO had a strong antibacterial activity against all strains including one Multidrug-Resistant (MDR) and two Methicillin-Resistant S. aureus strains. Inhibition …
Chemical composition and antibacterial activity of essential oil of Pulicaria odora L.
The chemical composition of the volatile oil constituent from Pulicaria odora L. roots has been analyzed by GC/MS. Twenty-seven components were identified, being thymol (47.83%) and its derivative isobutyrate (30.05%) the main constituents in the oil. Furthermore, the oil was tested against seven bacteria at different concentrations. Results showed that the oil exhibited a significant antibacterial activity.