Chiral separation membranes from modified polysulfone having myrtenal-derived terpenoid side groups

Novel polymeric materials, having a chiral environment, were obtained by the reaction of lithiated polysulfone with chiral terpenoid myrtenal. The resulting polymers gave self-standing durable membranes. Molecularly imprinted membranes were prepared from the novel myrtenal-containing polysulfones by the presence of print molecules during the membrane preparation process. The d-isomer imprinted membrane showed d-isomer adsorption and diffusivity selectivity, and vice versa. As a result, the d-isomer imprinted membrane transported the d-isomer in preference to the l-isomer, and vice versa. The control non-imprinted membrane also showed permselectivity toward racemic glutamic acid mixtures. The expression of permselectivity for the molecularly imprinted membranes was synergistically due to adsorption and diffusivity selectivity.     

Preparation of primary amine-modified gold nanoparticles and their transfection ability into cultivated cells

Cationic gold nanoparticles, prepared by reducing HAuCl(4) with NaBH(4) in the presence of 2-aminoethanethiol, formed a complex with plasmid DNA, and could be transfected into cultivated cells.     

Conformational analysis of the NMDA receptor antagonist (1S,2R)-1-phenyl-2-[(S)-1-aminopropyl]-N,N-diethylcyclopropanecarboxamide (PPDC) designed by a novel conformational restriction method based on the structural feature of cyclopropane ring

(1S,2R)-1-phenyl-2-[(S)-1-aminopropyl]-N,N-diethylcyclopropanecarboxamide (2b, PPDC), a new class of potent N-methyl-D-aspartic acid (NMDA) receptor antagonist, was designed based on a new method for restricting the conformation of compounds having a cyclopropane ring. The three-dimensional structures of PPDC obtained by the three different methods of X-ray crystallographic analysis, usual MM2-calculations in vacuum, and MM2 calculations based on the nuclear Overhauser effect (NOE) data in D2O are similar, which are in accord with that hypothesized. These results suggest that this conformational restriction method is particularly effective in designing novel biologically active molecules.     

Facially Dispersed Polyhydride Cu9 and Cu16 Clusters Comprising Apex-Truncated Supertetrahedral and Square-Face-Capped Cuboctahedral Copper Frameworks

By using a linear tetraphosphine, meso-bis[(diphenylphosphinomethyl)phenylphosphino]methane (dpmppm), nona- and hexadecanuclear copper hydride clusters, [Cu₉H₇(μ-dpmppm)₃]X₂ (X=Cl ( 1 a ), Br ( 1 b ), I ( 1 c ), PF₆ ( 1 d )) and [Cu₁₆H₁₄(μ-dpmppm)₄]X₂ (X₂=I₂ ( 2 c ), (4/3) PF₆⋅(2/3) OH ( 2 d )) were synthesized and characterized. They form copper-hydride cages of apex-truncated supertetrahedral {Cu₉H₇}²⁺ and square-face-capped cuboctahedral {Cu₁₆H₁₄}²⁺ structures. The hydride positions were estimated by DFT calculations to be facially dispersed around the copper frameworks. A kinetically controlled synthesis gave an unsymmetrical Cu₈H₆ cluster, [Cu₈H₆(μ-dpmppm)₃]²⁺ ( 3 ), which readily reacted with CO₂ to afford linear Cu₄ complexes with formate bridges, leading to an unprecedented hydrogenation of CO₂ into formate catalyzed by {Cu₄(μ-dpmppm)₂} platform. The results demonstrate that new motifs of copper hydride clusters could be established by the tetraphosphine ligands, and the structures influence their reactivity.     

MALDI-Q-TOF mass spectrometric determination of gold and platinum in tissues using their diethyldithiocarbamate chelate complexes

A rapid determination method is presented for gold (Au³⁺) and platinum (Pt⁴⁺) in tissues using matrix-assisted laser desorption ionization quadrupole time-of-flight mass spectrometry (MALDI-Q-TOF-MS). Au and Pt ions in wet-ashed tissue solution were reacted with diethyldithiocarbamate (DDC), and the resulting chelate complex ions Au(DDC)₂ ⁺ and Pt(DDC)₃ ⁺ were detected by MALDI-Q-TOF-MS using α-cyano-4-hydroxycinnamic acid as a matrix. The limit of detection (LOD) was 0.8 ng/g tissue and the quantification range was 2–400 ng/g for Au, and the LOD was 6 ng/g tissue and the quantification range was 20–4,000 ng/g for Pt. The Pt levels detected by MALDI-Q-TOF-MS in several tissues of a patient overdosed with cisplatin were nearly the same as those detected by flow-injection electrospray ionization mass spectrometry. The LODs of Au and Pt were 0.04 pg per well (sample spot) and 0.3 pg per well, respectively. To our knowledge, this is the first attempt to quantify Au³⁺ and Pt⁴⁺ ions in tissues by MALDI-Q-TOF-MS.

Direct perfluoroalkylation of non-activated aromatic C-H bonds of phenols

A simple procedure for the perfluoroalkylation of the aromatic ring of phenols under mildly basic conditions is described. Treatment of a variety of phenols with perfluoroalkyl iodide in the presence of the radical initiator V-70L and Cs₂CO₃ provided the corresponding perfluoroalkylated products in moderate to good yields. Generally, the reaction proceeded smoothly at room temperature to yield regioselectively perfluoroalkylated products.     

Topological factors governing the HOMO-LUMO band gap of the density of states of periodic hydrocarbon polymer networks

The band structures and density of states of 77 infintely large conjugated hydrocarbon polymer networks are calculated with HMO. A general rule for predicting whether the HOMO-LUMO band gap is zero or non-zero is proposed for an arbitrary hydrocarbon polymer network with periodic structure. The effects of bond alternation and of conjugate branching are discussed. Molecular design of high spin polymer networks is proposed.