Iwona Porwolik-Czomperlik

AIDS-related lymphoma screen results and molecular structure determination of a new crown ether bearing aziridinylcyclophosphazene, potentially capable of ion-regulated DNA cleavage action

The tetraaziridinyl PNP-lariat ether has been tested in the in vitro disease-oriented antitumor screen and evaluated further in an investigational AIDS-related lymphoma screen in vitro. This compound shows remarkable cytostatic activity. The crystal and molecular structure has been determined. The PNP-lariat ether has a pseudo-mirror plane perpendicular to the ring plane. The crown ether has an internal pseudo-threefold axis of symmetry. The so-called macrocyclic CC shortening effect is observed in the crown ether. All crown ether oxygen atoms are directed toward the interior of the ring and exist in an almost ideal envelope conformation. The cyclophosphazene ring is distorted from planarity and all PN bond lengths within the ring are equal with the mean value being 1.588(3) A.

Ion Flotation of Zinc(II) and Cadmium(II) in the Presence of Side-Armed Diphosphaza-16-Crown-6 Ethers

Competitive flotation of zinc(II) and cadmium(II) ions from dilute aqueous solutions by side-armed lariat ether-type derivatives of diphosphaza-16-crown-6 ethers in the presence of nonylphenol nonylethylene glycol ether as the non-ionic foaming agent has been investigated. The influence of the type of group attached to the PNP-lariat ether molecule on the selectivity and efficiency of Zn(II) and Cd(II) ion flotation is studied. An effect of alkali metal cations, i.e., Li+ and Na+, on Cd(II) ion-flotation removal is also reported. It was shown that the removal of Cd2+ increases with increase of pH values and decreases with alkali metal cations concentration increase in aqueous solutions. The correlation between selectivity coefficients of Cd(II)/Zn(II) and pH of aqueous solution as well as molar intrinsic volume and hydrophilic–lipophilic balance of studied ethers was found.

New Molecular Receptors with Cyclophosphazene Subunits: Synthesis, Reactivity, and Structure-Property Relationships

A series of hydrophopic ( 2 and 3) and new hydrophilic ( 4– 7) molecular receptors of the PNP-lariat ether with tetra-substituted cyclotriphosphazene subunits have been prepared by the complete nucleophilic substitution of chlorine atoms in the reactive PNP-crown precursor 1 with the respective sodium cation-paired oxyanions (phenoxy → 2, β-naphthoxy → 3, and methoxytrioxyethylenoxy → 4) and aliphatic amines (n-propylamine → 5 aziridine → 6, and pyrrolidine → 7). Their structures were established by MS and 31P NMR spectroscopy and their metal ion complexing properties tested by a TLC method. Comparison of the complexation behaviour for ligands 1– 7 shows that the affinity for particular cations is strongly substituent-dependent and, in general, is significantly enhanced by cooperation of the side arm donor atoms (O or N) with the parent PNP-crown structure in the binding process. The remarkable affinity of some ligands for selected cations, in particular lithium, cesium, and silver ions, is interpreted in terms of structure-property relationships.

Structure–alkali metal cation complexation relationships for macrocyclic PNP-lariat ether ligands

Water-insoluble, mono- and diarmed PNP-lariat ethers containing various aryloxy and regioisomerically-positioned binaphthylylenedioxy substituents linked to the phosphorus atoms of the cyclophosphazene ring via oxygen atoms are synthesized by regioselective, sodium ion-assisted arylolysis of tetrachloro-16-PNP-6 crown ether 1. Heterogeneously-substituted, mixed aryloxy-amino PNP-lariat ethers and bis-lariat ethers with two different substituents linked to the PNP-macrocycle via an oxygen and a nitrogen atom are prepared by stepwise arylolysis and aminolysis reactions of 1. The alkali-metal cation complexation behavior of the PNP-lariat ethers is evaluated in solvent polymeric membrane electrodes. The PNP-lariat and bis-lariat ethers exhibit pronounced selectivity for large alkali metal cations (Rb+ and Cs+) over small ones (Li+ and Na+). The selectivity is influenced by the configuration of the crown ether ring and the number of oxygen donor atoms in the ligand. For some PNP-lariat ethers, evidence for formation of 2 : 1 (ligand–metal ion) complexes with Rb+ and Cs+ is provided by ESI-MS.