We discover an important property of a small molecule ArCH(OMe)₂ which transforms catalytically inactive Pt(II)Br₂ procatalyst in situ to an powerful catalyst Pt(IV)-species for diverse annulation reaction. The powerful catalytic system enables selective activation of C₂-H/N-H and C₂-H/C₄-H of acetoacetanilide and C=O/C≡C of substituted butyne-1,2-dione for C-C/C-N, C-C/C-C and C-O/C-O bond-for...

A short, 5-step total synthesis of (±)-3-demethoxyerythratidinone from a simple pyrrole derivative is described. Features include the formation of gram quantities of a key tricylic aziridine from a challenging photochemical cascade reaction through the use of flow photochemistry. The final step involved a highly unusual Heck cyclization whereby ligand control enabled efficient formation of the ...

Over the last four years, there has been an explosion of knowledge about APCr and factor V Leiden. However, there remain a considerable number of difficult clinical areas in which there are no clear answers. Undoubtedly, factor V Leiden is commonly found in association with venous thromboembolic disease in whatever manifestation, but equally it has an unusually high frequency in the general pop...

This study analyzed uniaxial compression strength over time by preparing a homogel specimen from a bio grouting material, a cement-like form produced by environment-friendly microbial reactions. Among chemical grouting methods, the most commonly used method is the Labile Waterglass method. In this study, the homogel uniaxial compressive strength of Labile Waterglass (LW) injection material and ...

Binding of neopentylcobalamin and benzylcobalamin to the apoprotein of a haptocorrin from chicken serum has been demonstrated spectrophotometrically. The spectra of the protein-bound cobalamins strongly resemble those of base-on alkylcobalamins and show that when unbound these sterically hindered alkylcobalamins are only approximately 75% (benzyl) and 40% (neopentyl) base-on, at neutral pH and ...

Labile blood pressure elevation is believed to have less clinical significance than "fixed hypertension." This assertion was examined in the Framingham cohort of 5209 men and women followed for 20 years for the development of cardiovascular events in relation to three routinely measured blood pressures at each of 10 biennial examinations. Variability of pressure judged from the standard deviati...

Twenty-five Shigella strains were tested for their susceptibility to phagocytosis and killing by polymorphonuclear neutrophils (PMN). The studies identified several serum factors that could participate in opsonization. The strains varied remarkably in their susceptibility to killing when heat-stable opsonins were employed, but all strains were killed when exposed to heat-labile opsonins and PMN...

The activated form of aflatoxin B1 (AFB1) causes covalent modification primarily of guanine residues, leading to alkali-labile sites in DNA. A simple extension of the Maxam-Gilbert procedure for sequence analysis permits the identification of alkali-labile sites induced by AFB1 and determination of the frequency of alkali-labile AFB1 modifications at particular sites on a DNA fragment of known ...

This paper reviews applications of different LC–MS techniques for the analysis of natural compounds in foods. Specific examples of substances discussed are lipids, oligosaccharides, vitamins, flavonoids and related substances, phenolic compounds, glucosinolates, and other miscellaneous naturally occurring compounds in food products. LC–MS is a powerful technique in food analysis and especially ...

The chemical stabilization of labile fulleropyrrolidine N-oxides is achieved by encapsulation through intrarotaxane hydrogen bonding.