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Obtention de sels du type phosphoranimine-phosphonium qui sont des reactifs de synthese potentiels utiles

Ozone reacts very rapidly with alkylidenetriphenylphosphoranes 1a-d. In all cases we observed the cleavage of the P[dbnd]C bond and formation of triphenylphosphine oxide and the corresponding ketone 4a, 4b (R1 [dbnd] Ph) and alkene 4c (R1 [dbnd] H). Ozone also reacts with substituted phosphites 5a-b and gives the ozonides 7a-b.

The ozonization of various halophosphines 1a-j leads with quantitative yields to the corresponding phosphine oxides 2a-j. Ozonization is a convenient method of oxidation, in particular of compounds with bulky ligands (1c, 1d, 1e).

Les conditions d'elaboration de macrocycles, leurs complexation avec l'ion baryum sont decrites. Donnees spectrometriques de caracterisation des produits. Analyse elementaire effectuee par spectrometrie de masse

Ein 2:1-Gemisch aus Ozon und dem Diphosphen (I) ergibt bei tiefer Temperatur das relativ stabile Diperoxid (II), das mit Methanol zum Monoester (III) gespalten wird.

Aus den Perfluoralkyl-Olefinen (I) entstehen bei der Ozonolyse die bestandigen isomeren Ozonide (II) und (III).

Aus den Phenoxy-chlorphosphanen (I) entstehen mit Tetrahydrofurfurylalkohol (II) die gemischten Phosphorigsaureester(III), die mit Ozon zu den Trioxophosphetanen (IV) reagieren.

Les conditions d'elaboration de macrocycles, leurs complexation avec l'ion baryum sont decrites. Donnees spectrometriques de caracterisation des produits. Analyse elementaire effectuee par spectrometrie de masse

A convenient access to the first example of a 1,3,4,6-tetraphospha-hexatriene complex, a diphosphene bearing two cyclic dico-ordinated phosphorus substitutents and σ,η2-bonded to Fe(CO)4 units, and characterized by X-ray structure analysis, is described.

Suivant les conditions, la reaction de [Ph 4 P][HFe(CO) 4 ] avec PPhCl 2 donne soit le complexe PhP(H)ClFe(CO) 4 soit le complexe [Fe(CO) 4 [μ-Fe(CO) 4 ] (PPh) 2 ],, soit [Ph 4 P][Fe(CO) 4 ] 3 P 2 Ph 2 H]. Possibilite de preparation de [Et 4 N][(Fe(CO) 4 ] 2 W(CO) 5 P 2 Ph 2 H]

Obtention de sels du type phosphoranimine-phosphonium qui sont des reactifs de synthese potentiels utiles

International audience; In this article a new device based on 4 × 4 matrix micromachined resonating piezoelectric membranes used as DNA–DNA hybridization biosensor is proposed. This biosensor is operated in two fundamental different ways, namely integrated in a flow injection analysis (FIA) system and providing measurements by the “dip-and-dry” technique.After the fabrication and characterization phase of the micromachined resonating piezoelectric membranes, an appropriate FIA system for biosensing tests had to be developed. The biosensor functionality was validated in two ways: on the one hand the piezoelectric membranes have been used to measure the real-time kinetics of gold colloid adsorption, the whole matrix being integrated in the FIA system. The mass sensitivity of the device has been estimated to −3.6 Hz/pg which is by a factor of several hundreds better than of state-of-art values for piezoelectric mass-sensing devices. On the other hand, dip-and-dry technique has been used to measure the mass loading induced by the binding of streptavidin–conjugated gold nanoparticles to biotinylated target cDNA fixed onto the surface of the piezoelectric membranes. Measurement of resonant frequency of one piezoelectric membrane has been performed before and after adsorption of the streptavidin–conjugated gold nanoparticles and a 3.9 kHz shift of the resonant frequency has been recorded.These results indicate that micromachined piezoelectric membranes have real potential as micromechanical biosensors.

Two ways of synthesis of phosphorus dendrimers are elaborated up to the twelfth generation for one of them, to give a molecule which possesses 12288 functions. Examples of the reactivity of some dendrimers are described.

This paper is a review concerning metallic derivatives linked to the surface of phosphorus-containing dendrimers, that are dendrimers possessing one phosphorus at each branching point. The synthetic aspects will be described first, concerning in particular the complexation of transition metals (Fe, W, Rh, Pt, Pd, Ru) by monophosphine or diphosphine end groups, the grafting of metallocene derivatives (zirconocene and ferrocene), and the interaction with various clusters (Au-Fe, Au, Ti). Some applications of these metallo phosphorus dendrimers will be described in the field of materials science (modification of the surface of existing materials or creation of new materials), and in the field of catalysis (Stille couplings, Knoevenagel condensations, Michael additions).

The synthesis of dendrimers possessing gold atoms on the surface or inside the internal layers is reported. They have been shown to be precursors to mixed gold-transition metal cluster-containing dendrimers, which represent a new class of hybrid materials. The latter species are rather soluble in common solvents and can be characterized by spectroscopic methods. Moreover, gold-containing dendrimers are useful for making gold nanoparticles, which have very interesting electronic, optical, and catalytic properties.

The synthesis of two small dendrons (dendritic wedges) is reported and the reactivity of the functionality located at the core is studied. The first dendron has no reactive functionality on the surface, but possesses a vinyl group activated by a P=N-P=S linkage at the core; this vinyl group reacts slowly but cleanly with 2,3-dimethylbutadiene in Diels-Alder additions. The second dendron has aldehyde groups on the surface and one protected phenol group at the core. The deprotection occurs in very mild conditions, leading to a dendron having one phenol and four aldehyde groups. The reactivity of the phenol is demonstrated by the addition of a diisocyanate, affording a carbamate function and the grafting of an isocyanate group at the core of the dendron.

The synthesis of two new derivatives of Rhodamine B functionalized by phenols is reported. For one rhodamine derivative, the equilibrium between the open form and the ring-closed (spirolactam) form is completely shifted toward the latter, whereas the constitution of the other rhodamine derivative precludes ring closure. The spirolactam derivative was grafted as terminal group to a first generation phosphorus-containing dendrimer. Attempts to open the spirolactam form by adding HCl failed and resulted only in protonation of the NEt2 substituent of rhodamine.

Linear 1,2,3,4-heterohexatrienes of type H 2 C=CHP(R) 2 =NP(R') 2 =X (X = O, S) are used in Michael-type additions of various primary or secondary amines and hydrazines. The use of functionalized amines allowed the grafting of other functions, such as a double or a triple bond, a sulfide, an imidazole, or a phenol, and various types of NH 2 groups. These groups were used in condensation reactions, leading to the grafting of new functions such as phenols. Thus, the P(R) 2 =NP(R') 2 =X group appears as a new electron withdrawing group, very easily tunable by changing the R' or X substituents.

PN–PS linkages placed in some layers within dendritic architectures allow the grafting of several types of functional groups at site and depth specific places in the internal layers of phosphorus containing dendrimers. These functional groups are either organic derivatives (allyl, propargyl, isothiocyanate, amine, aldehyde, azide, crown-ether) or metallic derivatives (gold chloride, anionic zwitterionic zirconocene). Furthermore, the dendrimeric architecture is flexible enough to allow the growing of new dendrimers inside the internal voids of the initial dendrimer.

1,2 λ 3 azaphosphiridines 4a,b are obtained by reacting a dihalogenated phospha-alkene (Me 3 Si) 2 NPCCl 2 with two equivalents of lithium silylated amides.

We have obtained unusually stable secondaxy ozonides ( 2a-c ) by heating neat perfluoroalkenes ( 1a-c ) with ozone.

The unexpected synthesis of new free or complexed P-functionalized diphosphiranes is reported.

One of the possible ways of getting phosphacumulene complexes could be the complexation of phosphinoalkynes, which might induce the migration of hydrogen from phosphorus to the β carbon of the alkynyl group.

Ozonolysis of the diphosphene (1) occurs with a 2 : 1 stoicheiometry (ozone : diphosphene);the reaction carried out at low temperature, gives a relatively stable cyclic diperoxide(2).

Introduction: Our objective was to assess the capacity of dendrimer aza-bis-phosphonate (ABP) to modulate phenotype of monocytes (Mo) and monocytes derived dendritic cells (MoDC) activated in response to toll-like receptor 4 (TLR4) and interferon γ (IFN- γ) stimulation. Methods: Mo (n = 12) and MoDC (n = 11) from peripheral blood of healthy donors were prepared. Cells were preincubated or not for 1 hour with dendrimer ABP, then incubated with lipopolysaccharide (LPS; as a TLR4 ligand) and (IFN-γ) for 38 hours. Secretion of tumor necrosis factor α (TNFα), interleukin (IL) -1, IL-6, IL-12, IL-10 and IL-23 in the culture medium was measured by enzyme-linked immunosorbent assay (ELISA) and Cytokine Bead Array. Differentiation and subsequent maturation of MoDC from nine donors in the presence of LPS were analyzed by flow cytometry using CD80, CD86, CD83 and CD1a surface expression as markers. Results: Mo and MoDC were orientated to a pro-inflammatory state. In activated Mo, TNFα, IL-1β and IL-23 levels were significantly lower after prior incubation with dendrimer ABP. In activated MoDC, dendrimer ABP promoted IL-10 secretion while decreasing dramatically the level of IL-12. TNFα and IL-6 secretion were significantly lower in the presence of dendrimer ABP. LPS driven maturation of MoDC was impaired by dendrimer ABP treatment, as attested by the significantly lower expression of CD80 and CD86. Conclusion: Our data indicate that dendrimer ABP possesses immunomodulatory properties on human Mo and MoDC, in TLR4 + IFN-γ stimulation model, by inducing M2 alternative activation of Mo and promoting tolerogenic MoDC.

Dendrimers are multi-branched "tree-like" chemical entities. This family of non-linear polymers has already been applied in different fields. A dendrimer named ABP has shown some immuno-modulatory properties toward the Human immune system in vitro. This dendrimer is at the dawn to become a new therapeutic agent by itself for the treatment of inflammatory diseases in Human. Among human Peripheral Blood Mononuclear Cells (PBMC), the ABP dendrimer selectively targets human monocytes and induces an anti-inflammatory activation of these cells. This new study aims at understanding the interaction between the ABP dendrimer and human monocytes. Interestingly, a specific interaction was observed. Using, biological, physico-chemical and molecular modelling experiments we demonstrated that the ABP dendrimer triggers monocyte activation through receptor(s) recognition.; Les dendrimères sont des entités chimiques "arborescentes" multi-ramifiées. Cette famille de polymères non linéaires comporte des applications dans différents domaines. Un dendrimère nommé ABP a montré des propriétés immuno-modulatrices sur le système immunitaire humain in vitro. Ce dendrimère comporte le profil d'un nouvel agent thérapeutique pour être utilisé dans le traitement de maladies inflammatoires chez l'homme. Parmi les cellules mononucléaires du sang humain, le dendrimère ABP cible principalement les monocytes et induit une activation anti-inflammatoire de ces cellules. Cette nouvelle étude a visé à comprendre l'interaction entre le dendrimère ABP et les monocytes humains. De manière intéressante, une interaction spécifique a été observée. En utilisant des expériences de modélisation, de physico-chimie et de biologie moléculaire, nous démontrons que le dendrimère ABP induit une activation anti-inflammatoire des monocytes humains par l'intermédiaire d'un ou de récepteur (s).