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This work is devoted to examine the effectiveness of pyrazoles 4-(4,5-dihydro-1Hpyrazol- 5-yl)-N,N-dimethylaniline (D) on corrosion of mild steel in a 1 M HCl solution, using weight loss measurement at concentration effects. The inhibitor (D) was synthesized in our laboratory. The formation of this pyrazole was carried out with hydrazine and α-unsaturated aldehydes, and the structure was checked by spectroscopic means, such as FT-IR, 1H NMR and 13C NMR. Polarization curves and electrochemical impedance spectroscopy (EIS) methods were used to assess both the corrosion rate and inhibition efficiency. Potentiodynamic polarization showed that D behaved as a mixed-type inhibitor. The Nyquist plots showed that, while D concentrations increased, charge-transfer resistance increased and double-layer capacitance decreased, involving increased inhibition efficiency. Adsorption of the inhibitor molecules corresponds to Langmuir adsorption isotherm. Quantum chemical calculations showed that the inhibitor was prone to be protonated in the acid, and the results were in full agreement with experimental observations.

Aziridines constitute an interesting class of organic compounds because of their reactivity and the facility they can be converted into various derivatives. Our group has developed a new class of aziridines that show interesting biological activities such as antitumor and anti bacterial. This work describes new results of our ongoing research targeting new derivatives of biological interest.

Resume But de l’etude Il a ete demontre que les aziridines possedent une activite immunotropique marquee. Dans ce travail, les effets in vitro d’une aziridine nouvellement synthetisee (2-hydroxy-methyl-1(N-phtaloyltryptophyl) aziridine) sont determines sur la proliferation des lymphocytes humains stimules par les agents mitogenes, et sur la secretion des interleukines 2 et 6 (IL-2, IL-6). Materiel et methodes Les lymphocytes du sang peripherique sont isoles par centrifugation differentielle dans un gradient de Ficoll-Paque. Ils sont mis en culture en presence d’agents mitogenes (concanavaline A, lipopolysaccharide) et de differentes concentrations de l’aziridine testee. La determination de la proliferation lymphocytaire se fait par le comptage des cellules et par la methode du MTT [3-(4,5-Dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide]. Apres les differentes incubations, le dosage des IL-2 et IL-6 se fait par methode Elisa. Resultats L’aziridine utilisee stimule considerablement la proliferation des lymphocytes T et B, en absence ou en presence des mitogenes, a des concentrations allant de 1 μM a 1 mM, d’une maniere dose-dependante. De plus, l’aziridine induit une augmentation significative de la secretion des IL- 2 et des IL- 6. Conclusion La 2-hydroxy-methyl-1(N-phtaloyltryptophyl) aziridine est potentiellement immunostimulante et peut etre utilisee en immunotherapie a mediation non specifique, cellulaire ou humorale.

The title compounds can be prepared by a direct conversion of unprotected oximes using a Reformatsky reagent and anhydrous AlCl3 or triethylamine.

A practical synthesis of the title compounds from protected amino acylazides is described. All the compounds might be considered as a novel class of dipeptide isostere precursors; they all induce lymphocyte proliferation and protein production as observed from preliminary biological tests.

AIM OF THIS WORK: Aziridines have been shown to possess marked immunotropic activity. In this study, the in vitro effects of a new aziridine, 2-hydroxy-methyl-1-(N-phtaloyltryptophyl) aziridine, were determined on the proliferative responses of human lymphocytes stimulated by mitogens and on interleukin (IL-2, IL-6) secretion.Peripheral blood lymphocytes were isolated using differential centrifugation on a density gradient of Ficoll-Paque. They were cultured with or without mitogens (Concanavalin A and lipopolysaccharide), and with different concentrations of the aziridine. Proliferation was monitored by direct cell counts and confirmed by MTT [3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay. After different incubations, IL-2 and IL-6 were determined by using commercially available Elisa kits.The aziridine tested significantly stimulated the resting and mitogen T and B lymphocyte proliferation at concentrations between 1 microM and 1 mM, in a dose-dependent manner. It also increased IL-2 and IL-6 secretion.2-hydroxy-methyl-1-(N-phtaloyltryptophyl) aziridine displayed immunomodulatory properties and is potentially immunostimulant. It could be used to provide non-specific cell-mediated immune responses.

Aziridines have been shown to possess marked immunotropic activity. The aim of this work was to study the in vitro effects of different concentrations of three novel aziridines, 2-hydroxy-methyl-1-(N-phtaloylglycyl) aziridine (aziridine 1), 2-hydroxy-methyl-1-(N-phtaloylalanyl) aziridine (aziridine 2) and 2-hydroxy-methyl-1-(N-phtaloylphenylalanyl) aziridine (aziridine 3), on the proliferative responses of human lymphocytes stimulated by mitogens (concanavalin A (Con A) and lipopolysaccharide (LPS)), and interleukin-2 (IL-2), interleukin-6 (IL-6) secretion. The results showed that aziridines 1 and 3 significantly stimulated the resting and Con A or LPS lymphocyte proliferation at concentrations between 1 micromol/l and 1 mmol/l, in a dose-dependent manner, the action of aziridine 3 being the highest. They also increased IL-2 and IL-6 secretion. However, aziridine 2 had no effect on the resting lymphocyte proliferation in the absence of mitogens, at any concentration used, reduced Con A-stimulated T lymphocyte proliferation and LPS- stimulated B lymphocyte proliferation in a dose dependent manner and diminished IL-2 and IL-6 production. None of the three aziridines affected cell viability. In conclusion, the three aziridines used in this study displayed immunomodulatory properties. Aziridines 1 and 3 are potentially immunostimulant while aziridine 2 is immunosuppressive and could be used to provide nonspecific cell-mediated immune responses.

A practical synthesis of the title compounds from protected amino acylazides is described. All the compounds might be considered as a novel class of dipeptide isostere precursors; they all induce lymphocyte proliferation and protein production as observed from preliminary biological tests.

Vinylogous iminium salts from γ-aminoenamines react with triethylphosphite to afford amino phosphonates in moderate to good yields. The latter are easily converted to α-substituted aminoallylphosphonates that can yield α-substituted aminoallylphosphonates on reaction with butyllitium and a series of electrophiles.

Vinylogous iminium salts from γ-aminoenamines react with triethylphosphite to afford amino phosphonates in moderate to good yields. The latter are easily converted to α-substituted aminoallylphosphonates that can yield α-substituted aminoallylphosphonates on reaction with butyllitium and a series of electrophiles.