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Parallel batch screening experiments were carried out to examine how displacer chemistry and salt counterions affect the selectivity of batch protein displacements in anion exchange chromatographic systems. The results indicate that both salt type and displacer chemistry can have a significant impact on the amount of protein displaced. Importantly, the results indicate that, by changing the displacer, salt counterion, or both, one can induce significant selectivity changes in the relative displacement of two model proteins. This indicates that highly selective separations can be developed in ion exchange systems by the appropriate selection of displacer chemistry and salt counterion. The experimental batch screening data were also used in conjunction with various molecular descriptors to generate quantitative structure efficacy relationship (QSER) models based on a support vector machine feature selection and regression tool. The models resulted in good correlations and successful predictions for an external test set of displacers. A star plot approach was shown to be a powerful tool to aid in the interpretation of the QSER models. These results indicate that this modeling approach can be employed for the a priori prediction of displacer efficacy as well as for providing insight into displacer design and the selection of proper mobile-phase conditions for highly selective separations.

Research has been conducted on pareitropone. The synthesis of this compound carried out via the application of alkynyliodonium salt chemistry is described.

Research has been conducted on the optically active 4-methylcyclohexylidenemethyliodonium tetrafluoroborate. The preparation and solvolysis of this compound have been carried out in different solvents and the results indicate that the primary vinyl cation is not involved in the reactions.

Three different [KNO.sub.3] salts with [[delta].sup.18]O values ranging from about -31 to +54 [per thousand] relative to VSMOW were used to compare three off-line, sealed glass tube combustion methods (widely used for isotope studies) with a more recently developed on-line carbon combustion technique. All methods yielded roughly similar isotope ratios for [KNO.sub.3] samples with [[delta].sup.18]O values in the midpoint of the [[delta].sup.18]O scale near that of the nitrate reference material IAEA-NO-3 (around +21 to +25[per thousand]). This reference material has been used previously for one-point interlaboratory and intertechnique calibrations. However, the isotope ratio scale factors by all of the off-line combustion techniques are compressed such that they are between 0.3 and 0.7 times that of the on-line combustion technique. The contraction of the [[delta].sup.18]O scale in the off-line preparations apparently is caused by O isotope exchange between the sample and the glass combustion tubes. These results reinforce the need for nitrate reference materials with [[delta].sup.18]O values far from that of atmospheric [O.sub.2], to improve interlaboratory comparability.

A novel transduction chemistry for preparing optical anion-selective polymeric films that respond reversibly and selectively to chloride ion activity is demonstrated. The chloride sensors are prepared by casting thin (5-10 [micro]m) plasticized PVC films containing indium(III) octaethylporphyrin hydroxide, along with optimized levels of a lipophilic tetraphenylborate salt, onto glass slides. When bathed in low-pH buffered solutions void of chloride, the porphyrin species spontaneously forms a hydroxide ion-bridged dimer, with the added lipophilic borate species serving as the counteranion for this complex. The maximum for the Soret absorption band of this dimeric species is shifted to 390 nm, from 410 nm for the initial monomeric porphyrin. Increases in chloride ion levels in the bathing solution results in chloride extraction and ligation to the [In.sup.III] center, and concomitant breaking of the dimer into monomeric porphyrin species, yielding a decrease in absorbance at 390 nm and an increase in optical signal at 410 nm. Under optimized conditions, optical selectivity coefficients toward chloride over a wide range of other anions (N[O.sub.3.sup.-], Cl[O.sub.4.sup.-], SC[N.sup.-], S[O.sub.4.sup.2-], [F.sup.-], [Br.sup.-], [H.sub.2]P[O.sub.4.sup.-]) are measured to be < [10.sup.-3]. Of all anions tested, only salicylate yields a slightly greater response than chloride. This selectivity is shown to be adequate for reversible and accurate sensing of chloride levels in diluted serum samples.

Research has been conducted on the copper(I)-acetonitrile complexes. The synthesis of the two-coordinate copper(I) compound ligated by nitrile ligands has been carried out and the results indicate that use of this compound for copper(I) complex synthesis can lead to solubility in low-dielectric solvents.

Pseudo-steady-state and time-resolved chemically-induced dynamic nuclear polarization (CIDNP) experiments were done to study the photodecomposition of triphenylsulfonium hexafluoroantimonate. 9,10-dimethylanthracene and naphthalene were used as the singlet sensitizers. Results indicated that the deactivation pathways of the radicals differ considerably based on CIDNP spectra. This finding arises from the observation that the intermediate phenyl radical can abstract hydrogen from the radical cation of 9,10-dimethylanthracene but not that of naphthalene.

Research has been conducted on carboxy-substituted alkylammonium salt. The preparation of this salt and its use as incoming carboxylate ligand in a ligand-exchange reaction to produce Mn (sub)12 single-molecule magnet are described.

Research has been conducted on silver(I) double salts containing 4-hydroxyquinoline ligand. The authors describe the synthesis of these salts carried out via the hydrothermal method.

Research has been conducted on metal-centered ferrocene compounds. The authors report that these compounds have been designed via the use of 5-ferrocenylpyrimidine and ferrocenylpyrazine, and that when combined with transition metal salts they produce structurally diverse mixed-metal polynuclear complexes.

Research has been conducted on zeolite continuous coating formation. The authors have reversed the surface charge of the exposed catalyst's surface via the use of copolymer of acrylamide and methyl chloride quaternary salt.

Research has been conducted on noncyclic [10-S-5] sulfuranide dioxide salts with three S-C bonds. The authors describe the synthesis of these compounds which started from various sulfur electrophiles, and their characterization.

Research has been conducted on quaternary salts of pyridine, pyridazine, N-methyl imidazole and N-propyl triazole containing pentafluorosulfanyl. The authors describe the preparation and characterization of these salts carried our via the use of (super)13 C NMR and IR spectra and elemental analyses.

Research has been conducted on pyridine-2-dicarboxylic-, pyridine-2,6-dicarboxylic- and pyridine-2,4-dicarboxylic acids and their salts. The authors demonstrate that these compounds react with triply bonded dirhenium(II) complex is respond to ethanol, and produce unsymmetrical substitution products where N,O represents a chelating pyridine-2-carboxylate ligand.

Research has been conducted on [Ge (sub)9 =Ge (sub)9 =Ge (sub)9 =Ge (sub)9] (super)8-, a tetramer possessing nine-atom deltahedral germanium clusters and charge 8-. The authors describe the characterization of this compound as salt.

Research has been conducted on oxadiazole-containing rigid bidentate ligands with inorganic Ag(I) salts. The authors have invetsigated the coordination chemistry of these ligands, and present the results.

Research has been conducted on angular trinuclear copper(II) complexes containing Schiff base obtained from salicylaldehyde condensation. The authors describe the preparation of these complexes in the presence of imidazole, and their isolation as perchlorate salts.

Research has been conducted on copper(III) complexes of bis(tacn) ligands. The authors describe the preparation of these complexes via the reaction of Cu(II) salt with L.6HCl in neutral aqueous solution.

Research has been conducted on uranyl and strontium nitrates, and uranyl chlorides. The authors have compared the solvation of these compounds in room-temperature ionic liquids, and have presented the results.

Research has been conducted on alkene aziridination. The authors describe the location of transition structures for this aziridination via the use of substituted oxaziridines and diaziridinum salts.

The authors review the publications on box ligands with pyridine ring as a spacer. The topics include the synthesis of these ligands, the preparation of the catalysts via the reaction of pybox with inorganic salts, and the characterization of pybox ligands via the single-crystal X-ray structural study.

Research has been conducted on mu-phenoxo-bis-mu-acetato di-manganese(II) complex using BpmpH ligand. The authors describe the isolation of this complex as a perchlorate salt, and report that X-ray structure of the complex has two manganese(II) ions which are in a distorted octahedral environment.

Research has been conducted on 2D bilayer cobalt(II)-organic framework with nanoscale rectangular channels clathrating large organic molecules. The authors describe the synthesis of this framework carried out via the reaction of cobalt(II) salt with 5-nitro-1,3-benzenedicarboxylic acid and 1,2-bis(4-pyridyl)ethylene.

Research has been conducted on tetracycline derivatives. The authors report the synthesis of these derivatives which utilizes Suzuki, Heck and other palladium-coupling reactions by means of tetracycline iodoarene and arenediazonium salts.

Research has been conducted on tridentate Schiff base carboxylate ligands. Results demonstrate that these ligands react both with copper trifluorate salt to produce helical chain complex and with copper nitrate to give tetranuclear complex with azide salt.

Research has been conduucted on copper(I)-acetonitrile solutions. The authors report that the study of Cu (super)63 NMR line width in these solutions has been carried out, and that different variants of Cu(I) salt concentrations, added salts, chloride ion, water and temperature have been investigated.

Research has been conducted on silylketene dithioacetal. The authors demonstrate that the acid-catalyzed reactions of this compound with imines or iminium salts produce gamma,gamma-bis(ethylthio)allylamines.

Research has been conducted on terephthalic acid, salicylidene alkylimine, NaOH and inorganic manganese(II) or (III) salt. Results demonstrate that the reaction system consisting of these compounds produses dinuclear manganese complexes.

Research has been conducted on diimine-type ligands. The authors describe the reactions of protic nucleophiles with these ligands carried out in the presence of iron(II) salts.

Research has been conducted on tripodal ligands. The reaction of these ligands with metal salts has been carried out, and the results demonstrate that this reaction has produced two-dimensional metal-organic frameworks.

Research has been conducted on soluble hexa-peri-hexabenzocoronene. The synthesis of this compound carried out from hexaphenylbenzene is described.

Research has been conducted on K (sub)5 Bi (sub)4 metallic salt. The authors have investigated the electronic structure of this salt via the use of first-principles density functional calculations, and they report that alkali and pnictide orbitals contribute to the stability of the compound.

Research has been conducted on ionic salts of ruhtenium(IV). The authors describe the synthesis of these salts, and demontrate that their structures have been determined via single-crystal X-ray diffraction.

Research has been conducted on bicyclic sulfonium salts. The authors discuss the enantioselective synthesis of these compounds or swainsonine derivatives' thioanalogues which is based on a stereo- and regiospecific transannular cyclization reaction of cyclic sulfides.

Research has been conducted on vinamidinium salts. The authors report the use of the derived from dimedone enaminones as starting materials, and the presence of rotameric vinamidinium salts as well as diastereomeric vinylogous imidate salts characterized via (super)1 H NMR.

The author discusses publications on polyvalent iodine compounds, such as pentacoordinate I(V) and tricoordinate I(III). The topics of interest include the role of these compounds in contemporary organic chemistry, and the chemistry and uses of aryl-, alkenyl- and alkyliodonium salts in synthetic and preparative organic chemistry.

Research has been conducted on [Cu (super)II (hfac) (sub)2 (TTF-py) (sub)2](PF (sub)6).2CH (sub)2 Cl (sub)2 where hfac=4-(2-tetrathiafulvalenyl-ethenyl. The authors describe the preparation, EPR data, X-ray crystal structure and magnetic measurements of this compound in which localized spin and conducting systems are covalently linked via conjugated bridges.

Research has been conducted on beta-amino alcohols produced by cyclohexene oxide and containing alpha-phenylethyl auxiliaries. The authors report that these compounds act as chiral promoters during the addition of diethylzinc to benzaldehydes.

Research has been conducted on [3+3] cycloaddition reaction . The description of this reaction carried out via the use of 4-hydroxy-2-pyrones and 1,3-diketones is presented.

Research has been conducted on ethyl N-[(2-Boc-amino)ethyl]glycinate and its hydrochloride salt. The improved synthesis of these compounds is described.

Research has been conducted on century-old copper salt. The authors report their study of the structure, magnetism and spectroscopy of this salt.

Research has been conductyed on noncentrosymmetric solids. The isolation of these solids by high-temperature salt-inclusion reactions has been carried out, and the results demonstrate that copper(II) phosphates have open-framework structures templated by Cs-Cl salts.

Research has been conducted on homochiral metal carboxylate coordination polymers. The synthesis of these compounds carried out via the treatment of 2,2'-dihydroxy-1,1'-binaphthalene-6,6'-dicarboxylic acid with metal salts at high temperatures is described.

Research has been conducted on stable amino-aryl-carbene. The authors report acid-promoted isomerization of this compound into a transient azomethine ylide.

Research has been conducted on 1-phenyl-1-benzothiophenium triflates. The authors report the results of the [4+2]-cycloaddition reaction of these compounds.

Research has been conducted on Cu (super)II salts. The authors describe the reaction of these salts with 2,5-bis(3-pyridyl)-1,3,4-oxadiazole in CH (sub)3 CN-H (sub)2 O medium, and report that the reaction leads to the complexes with the solid structures controlled by choice of counteranions.

Research has been conducted on natural agelastatin A and agelastatin B. The syntheses of these compounds have been carried out via the strategy developed to utilize a lkynyliodonium salts- alkylidenecarbene- cyclopentene transformation converting amino alcohol derivative to agelastatin system's functionalized core, and the results are discussed.