Phosphorylated macrocycles: structures,complexing properties,and molecular recognition

Procedures were developed for functionalization of macrocycles by introducing a phosphonic group either directly linked to the aromatic rings (in the case of cyclophanes or calixarenes) or as a pendant arm. For these compounds to be used as artificial receptors for amino alcohols and amino acids, the host molecule must possess not only negative charges arising from the phosphonate moieties but also a hydrophobic binding site, such as electron-rich aromatic residues. We designed inter alia new dissymmetric macrocycles capable of being involved in three binding modes with guest molecules, viz., hydrogen bonding, electrostatic attraction, and π-cation interactions. The NMR characterization of the macrocycles, their stereochemistry in solution and in the solid state, and the use as chiral receptors for biologically relevant molecules are described. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1313–1330, June, 2005.     

Studies on the Middle-phase Microemulsion of Lauric-N-methylglucamide

The phase behaviour of the middle-phase microemulsion for the quaternary system lauric-N-methylglucamide （MEGA-12）/n-butanollalkane/water has been studied with Winsor type, δ-γ, fishlike and novel ε-β fishlike phase diagrams. A series of phase inversions Winsor I （2）→Ⅲ（3）→Ⅱ （ 2 ） were observed for the three kinds of phase diagrams. The phase types, the phase volumes and the range of alcohol concentrations from the beginning to the end of the middle-phase microemulsion were obtained from Winsor phase diagram. From δ-γ, fishlike phase diagram, the physicochemical parameters, such as the mass fraction of n-butanol in the hydrophile-lipophile balanced inteffacial layer, A^s, the coordinates of the start and end points of the middle-phase microemulsion, and the solubilities of MEGA-12 and n-butanol in alkane phase were calculated. The novel ε-β fishlike phase diagram was also presented. From this kind of diagram, the above experimental phenomena were observed and the physicochemical parameters were calculated precisely. The novel fishlike phase diagram has advantages over the Winsor and δ-γ fishlike phase diagrams in the evaluation of the solubilization power of the microemulsion and calculation of the related physicochemical parameters.     

New cleft-like molecules and macrocycles from phosphonate substituted spirobisindanol

We have synthetized medium-sized cyclophanes and macrocycles containing phosphonic groups, directly linked to the aromatic rings of the phanes or as pendant arms,for use as specific receptors for the selective complexation of neutral guests or for complexing lanthanides, as luminescent sensors and for diagnostic bioassays in medicine.Furthermore, because it would be of great interest for biochemistry as well as for pharmacological studies to dispose of preorganized rigid chiral hosts for biorelevant molecules we designed inter alia, some new chiral macrocycles capable of a triple binding mode and we used them for constructing macrocycles that could also be of interest for chiral recognition and chiral separations. Thus, in this paper we shall review the salient aspects of some macrocycles synthetized in our laboratory, all possessing the phosphonate moiety and a spirobisindanol scaffold and able to act as complexing agents for cations and organic substrates. In particular, we shall describe their NMR characterization, their stereochemistry in solution and in the solid state, and their use as chiral receptors for biorelevant molecules. Chiral HPLC resolution of some of them is also reported.     

Periodic Solutions for p-Laplacian Neutral Functional Differential Equation with a Deviating Argument

In this paper, by using the continuation theorem of coincidence degree theory and some analysis methods, we study a kind of periodic solutions to p-Laplacian neutral functional differential equation with a deviating argument,some new results on the existence of periodic solutions is obtained.     

利用有限域上奇异伪辛几何构作具有仲裁的认证码

利用有限域上奇异伪辛几何构作了一个新的具有仲裁的认证码,计算了这个码的参数,当发方编码规则和收方解码规则按等概率分布选取时,计算出各种攻击成功的概率.     

Asymmetric Olefins Hydroformylation. VI. Asymmetric Hydroformylation of Isomeric Butenes Using Platinum Catalysts

The asymmetric hydroformylation of the straight chain butenes with the [(?)-DIOP]PtCl₂-SnCl₂ catalytic system shows that asymmetric induction, contrary to the rhodium-(?)-DIOP catalytic system, takes place after the intermediate metal-alkyl-complex formation.     

Efficient Hydrolysis of RNA by a PNA - Diethylenetriamine Adduct

The introduction of a urea bond linking a protected diethylenetriamine (DETA) unit and the terminal amino group of a resin-bound peptide nucleic acid (PNA) decamer gave access to a PNA - DETA adduct (shown here), which hydrolyzed the target 25-mer RNA rapidly and sequence specifically.     

Novel Cs‐Symmetric 1,4‐Diphosphine Ligands in the Copolymerization of Propene and Carbon Monoxide: High Regio‐ and Stereocontrol in the Catalytic Performance

New C_s‐symmetric aryl 1,4‐diphosphine ligands were synthesized and tested in the copolymerization of carbon monoxide and propene. The electronic properties of the two different P‐atoms did not affect the high enantioselectivity of the catalyst precursors, thus resulting in high ‘regio’‐ and ‘stereoregular’ copolymers.     

Crystal Structures of the (−)-DIOP Complexes of Nickel,Palladium and Platinum Dichloride

The crystal structures of PdCl₂[(?)-DIOP], PtCl₂[(?)-DIOP] and of NiCl₂-[(?)-DIOP] have been determined by X-ray analysis and refined by least-squares methods [(?)-DIOP=(?)-2,2-dimethyl-4,5-bis(diphenylphosphinomethyl)-1,3-dioxolane]. The coordination around the nickel atom is tetrahedral, the coordination around palladium and platinum is square planar. The unit cell of the palladium complex contains two non-equivalent molecules with different conformations of the seven-membered chelate ring involving the metal and the two phosphorus atoms. PtCl₂[(?)-DIOP] is isostructural with the corresponding palladium complex.