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The focus is to expand the original design of fast photochemical oxidation of proteins (FPOP) and introduce S[O.sub.4.sup.-x], generated by 248 nm homolysis of low millimolar levels of persulfate, as a radical reactant in protein footprinting. FPOP is a chemical approach to footprinting proteins and protein complexes by 'snapshot' reaction with free radicals. The radical used until now is the OH radical, and it provides a measure of residue-resolved solvent accessibility of the native protein. We show that FPOP can accommodate other reagents, increasing its versatility. The new persulfate FPOP system is a potent, nonspecific, and tunable footprinting method; 3-5 times less persulfate is needed to give the same global levels of modification as seen with OH radicals. Although solvent-exposed His and Tyr residues are more reactive with S[O.sub.4.sup.-x] than with [sup.x]OH, oxidation of apomyoglobin and calmodulin shows that [sup.x]OH probes smaller accessible areas than SO4-', with the possible exception of histidine. His64, an axial ligand in the heme-binding pocket of apomyoglobin, is substantially up-labeled by S[O.sub.4.sup.-x] relative to [sup.x]OH. Nevertheless, the kinds of modification and residue selectivity for both reagent radicals are strikingly similar. Thus, the choice of these reagents relies on the physical properties, particularly the membrane permeability, of the radical precursors. 10.1021/ac101760y

Research has been conducted on biosynthetic thiolase. The intermediates of the thiolase reaction site have been investigated via crystallographic analysis, and the description of the structural events taking place at thiolase active site during the catalytic cycle is presented.

Research has been conducted on pi-electron tetrapnictogen dianions in Na (super)+ Pn (sub)4 (super)2- (Pn= Sb, As, P). Results demonstrate that from being aromatic these dianions become antiaromatic upon electron detachment and yield inorganic antiaromatic Na (super)+ Pn (sub)4 (super)- molecules.

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 chainlike coordination polymer [Cu (super)II (2,2'-bipy)(H (sub)2 O) (sub)2 Al(OH) (sub)6 Mo (sub)6 O (sub)18] (sub)n (super)n- formed from [Al(OH) (sub)6 Mo (sub)6 O (sub)18] (super)3-. Results have demonstrated that the structure of this polymer is based on Anderson type of polyanion and a transition metal complex with organic ligand.

Research has been conducted on multi-nickel-substituted heteropolytungstates. The authors describe the synthesis and characterization of these complexes via elemental analysis, IR, electrochemistry and magnetic studies.

Research has been conducted on dimethyldiaryltin reagents. The reaction of these reagents with BCl (sub)3 leads to the corresponding diarylchloroboranes.

Research has been conducted on 8-coordinate zirconium compound. The authors describe the synthesis and characterization of the complex carried out via elemental analysis, single-crystal X-ray diffraction, and NMR and vibrational spectroscopies.

Research has been conducted on copper(I) halides. The authors describe the reactions of these compounds with bis(diphenylselenophosphinyl)alkanes in acetonitrile.

Research has been conducted on spherical Lindquist type polyoxometalate compound. The authors describe the use of this compound as a noncoordinating anionic template for construction of three-dimensional lanthanide-aromatic monocarboxylate dimer supramolecular networks.

Research has been conducted on boron subhalide cluster dianions. The authors report the two step electrochemical oxidation in the B (sub)6 X (sub)6 series, where X is Cl, Br, I, and that this oxidation leads to unstable two-electron oxidation of the dianionic starting compounds' products.

Research has been conducted on non-centrosymmetric solid Ba (sub)2 MnSi (sub)2 O (sub)7 Cl. The authors describe the isolation of this compound via salt-inclusion high-temperature reactions, and report that this manganese(III) silicate chloride adopts the fresnoit structure with pseudo-one-dimensional channels with Ba (super)2+ cations.

Research has been conducted on coordination polymers which use [Au(CN) (sub)4] (super)- anion as a building block. The authors describe the preparation of these polymers.

Research has been conducted on higher fullerene anions with different sizes and shapes. The authors describe their experimental and theoretical study of these anions, and the results of this study indicate the formation of hexaanions.

Research has been conducted on [(PW (sub)11 O (sub)39) (sub)2 (H (sub)4 Mo (sub)4 S (sub)4 O (sub)6)] (super)10- anions. The authors demonstrate that these anions have been produced via stereospecific addition of the oxothiocation to the monovacant anion.

Research has been conducted on n-octymesylate. The authors have investigated the nucleophilic displacement of this compound with different anions carried out under liquid-supercritical phase-transfer catalysis conditions such as supercritical carbon dioxide and water, and have described the results.

The authors review the publications on carbon nucleophiles' conjugate addition to unsaturated nitriles. The topics of interest include the prerequisites for conjugate additions of carbon nucleophiles to alkenenitriles.

Research has been conducted on alpha,alpha'-stabilized carbanion complexes. The uthors describe the synthesis of these complexes carried out via metalation of (organo)sulfonylacetonitriles by BuNa, BuLi or BnK in THF solution.

Research has been conducted on alpha- and beta-rotational isomers of Wells-Dawson structure. The authors have investigated the relative stability of these isomers via calculation of oxidized, single- and 2-folded-reduced systems by density finctional theory calculations.

Research has been conducted on enolate anions of cycloalkanones. The authors demonstate that these anions nucleophilically open cyclopentene and cyclohexene, and that the anions formed regiospecifically by means of kinetic deprotonation of 2-cyclohexenone and 2-cycloheptenone open cyclohexene oxide.

Research has been conducted on 2-naphthoxide ion. The authors demonstrate that this ion has been quenched by aromatic and aliphatic halides in order to produce alkyl and aryl radicals via concerted C-X bond fragmentation reaction.

Research has been conducted on carbamates. Results demonstrate that the synthesis of these compounds involve utilization of toxic reagents, therefore the safer alternative synthetic methods have been investigated and are discussed.

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 conducted on Mn (super)II compounds with phenylcyanamido ligands. The authors describe the synthesis and characterization of these compounds via the single-crystal X-ray structural analysis, and report that the compounds have nuclearity from mononuclear and dinuclear systems to 1D and 2D networks where X-phenylcyanamide anions act as bridging ligands.

Research has been conducted on (SO (sub)2) (sub)2 N (sub)3 (super)- anion. The authors report that this anion has been characterized via the use of single-crystal X-ray diffraction.

The new niobate and tantalate derivatives are easily prepared in good yield in acqueous solution, starting with [M(CO)3(CH3CN)(sub 3)](super +1) or under hydrothermal conditions starting with [(M(CO)5Br]. The compositions and structures of the new complexes are established by elemental analysis, by infrared and (super 17)O NMR spectroscopy and by single-crystal X-ray diffraction of five salts.

The interaction of a methyl group with three transition metal atoms in solid state and in solution has been studied on the Re(sub 3)(mu-H)(sub 3)(mu(sub 3)-CH(sub 3)(CO)(sub 9))(super -) anion. The latter was the product of the reaction between Re(sub 3)(mu-H)(sub 3)(mu(sub 3)-CH(sub 3)(CO)(sub 9))(super -) with CH2N2. NMR data reveal that the anion has symmetry on C(sub 3v) which agrees with its solid-state structure.