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The lanthanide-tuned structural and magnetic characterization of magnetic materials based on the use of 2,2':6',2'-terpyridine (terpy) as a blocking ligand at the [Ln.sup.III] center which forms isomorphous cyano-bridged compounds is demonstrated.

A rapid and stereodivergent access to polyhydroxylated 10-azabicyclo[4.3.1]decanes as new calystegine analogues is achieved by a double benzotriazolyl/carbon nucleophile exchange followed by a ring-closing metathesis. The analysis of new compounds as glucocerebrosidase inhibitors is presented.

[Mn(super III)(salen)(H2O)(super +1)[salen = the N,N' -ethylenebis(salicylideneaminato) dianion], which has a high-spin ground state (S = 2), as a building block is studied. Results suggest the possibility of design and construction of single molecule magnets or high-spin molecules based on Schiff-base cationic precursors and octacyanometalates.

ABSTRACT New and original heterocyclic α-enamido phosphine chiral solutes were prepared: four structurally similar racemates with the chirality center placed on the phosphorus atom, and four other related pairs of enantiomers with chirality borne by the carbon atoms of the phospholane ring. The structural variations were placed on an aliphatic heterocycle (six- or seven-member rings) and on the carbamate function (methyl or t-butyl). Their separation was achieved on a commercial cellulose tris-(3,5-dimethylphenylcarbamate) stationary phase (Lux Cellulose-1, Phenomenex) in supercritical fluid chromatography (SFC). The effects of molecular structure on SFC retention and enantioresolution were studied. Among these eight pairs of enantiomers, some reversal of elution order between similar compounds was observed. The effect of changing the organic solvent (methanol and ethanol) and its proportion (between 5 and 40%) in the mobile phase was investigated. Retention data were collected over the temperature range 0-50 °C, and the results interpreted from thermodynamic aspects. Chirality, 2013. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Describes the crystal structure of Pseudomonas 7A glutaminase-asparaginase (PGA) solved at 1.7 A resolution by the molecular replacement method. Experimental procedure; Protometer structure; Electron density; pH.

Depending on pH, arylsulfatase A exists in solution as a dimer or as an octamer. The enzyme isolated from human placenta was crystallized at pH 5.4 in a new crystal form with space group C2, unit-cell parameters a = 154.0, b = 190.3, c = 112.5 Å, β = 122.4° and four subunits in the asymmetric unit. At pH 6.5-6.7, tetragonal crystals are obtained that are isomorphous to the known crystals of recombinant arylsulfatase A obtained at pH 5.0-5.4. The crystal structure of both forms was determined by the molecular-replacement method. The monoclinic crystals contain octamers of the same type as found in the tetragonal form. [ABSTRACT FROM AUTHOR]

The structural data for sodium 2-hydroxy-5-nitro­benzyl­sulfonate monohydrate, Na+·C7H6NO6S−·H2O, which mimics an artificial substrate for human aryl­sulfatase A, viz. p-­nitrocatechol sulfate, reveal that the geometric parameters of the substrate and its analogue are very similar. Two water mol­ecules, the phenolic O atom and three sulfonate O atoms form the coordination sphere of the Na+ ion, which is a distorted octahedron. The Na+ cations and the O atoms join to form a chain polymer. [ABSTRACT FROM AUTHOR]

Abstract: A novel and efficient approach for the synthesis of phosphine-containing α-amino acids bearing quaternary carbon is described. The key step involves the original nucleophilic addition of lithiated phosphines onto acyclic ene-carbamates concomitant with a spontaneous internal (N→C) alkyloxycarbonyl migration. [Copyright &y& Elsevier]