The reaction of the oxidorhenium(V) precursor [ReOCl(3)(PPh(3))(2)] with the proteinogenic amino acid L-histidine (L-hisH) and the glycosides methyl alpha-D-mannopyranoside (Me-alpha-D-Manp) and methyl beta-D-ribopyranoside (Me-beta-D-Ribp) in methanol/triethylamine yielded the crystalline compounds [ReO(L-his)(Me-alpha-D-Manp2,3H(-2))] x 2MeOH (1) and [ReO(L-his)(Me-beta-D-Ribp3,4H(-2))] x (1/...

We describe the design and synthesis of substrate and internal standard conjugates for application in profiling enzyme activity of the enzymes alpha-D-2-deoxy-2-N-sulfonamido-glucosamine sulfamidase, alpha-D-2-deoxy-2-N-acetyl-glucosamine hydrolase, acetyl-coenzymeA:alpha-D-2-deoxy-2-amino-glucosamine transferase, and alpha-D-2-deoxy-2-N-acetyl-glucosamine-6-sulfate sulfatase. Deficiency of any...

Plasmodium falciparum malaria kills roughly 2.5 million people, mainly children, annually. Much of this mortality is thought to arise from the actions of a malarial toxin. This toxin, identified as glycosylphosphatidylinositol (GPI), is a major pathogenicity determinant in malaria. A malarial molecule, Pfj, labeled by [3H]glucosamine like the GPIs, was identified as a non-GPI molecule. Here we ...

We report a fast, simple high-performance liquid-chromatographic assay for serum alpha-tocopherol, with use of a reversed-phase column and tocol as internal standard. Only 200 microliter of serum is required. Isocratic elution of the n-hexane extract is done within 6 min; total analysis time is less than 1 h. Within-day precision (CV) was 2.3% for 24 samples of a normal plasma pool (mean concn,...

Mono- and sesquiterpenes were used for the traceability of a typical Piedmont (Italy) mountain ricotta cheese produced by nine mountain farms. For each farm a sample of ricotta cheese was collected every 7 days during mountain grazing and analysed using headspace solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). Obtained results showed the presence of about 20 monot...

Activation of the phenolic pathway is known to be part of a defense response against cell wall-derived elicitors from pathogens. Many examples of a defense response by increasing the synthesis of phenolic compound against the elicitor were demonstrated in the past, but the elicitor structure has so far been poorly characterized. Our results indicate that a disaccharide fraction containing the f...

A diastereoisomer (alpha, beta, and gamma) specific analytical method for measuring hexabromocyclododecanes (HBCDs) was developed using liquid chromatography-tandem mass spectrometry (LC-MS-MS). The method developed was applied to analyze blubber of small cetaceans to divulge the distribution and temporal variation of HBCDs in the Asian marine environment. HBCDs were detected in all the blubber...

A new liquid chromatography/mass spectrometry (LC/MS) method is described for relative quantification of phosphoproteins to simultaneously compare the phosphorylation status of proteins under two different conditions. Quantification was achieved by beta-elimination of phosphate from phospho-Ser/Thr followed by Micheal addition of ethanethiol and/or ethane-d(5)-thiol selectively at the vinyl moi...

N-Heterocyclic carbene (NHC)-mediated ring-opening polymerization (ROP) of N-substituted N-carboxylanhydride ((N)R-NCA) yields cyclic poly(alpha-peptoid)s with controlled molecular weights (M(n) = 3-30 kg mol(-1)) and narrow molecular weight distributions (PDI = 1.04-1.12). The reactions exhibit characteristics of a living polymerization with minimal chain transfer. This enables the facile synt...