1. Azoproteins are shown to have the property of spreading when introduced intradermally into the rabbit skin. 2. The aromatic derivative selected for the coupling does not affect specifically the spreading property of the azoprotein. Likewise, the type of protein has no importance, except in quantitative respects. 3. The spreading property conferred upon a protein by coupling appears to derive...

It has been reported that trypan blue, a diazo dye with polyamphipathic structure, can inhibit the coupling of receptors to G-proteins. The present study was carried out to investigate the effect of trypan blue on the actions of adrenoceptor agonists in the guinea-pig atrium. Trypan blue (10 and 100 microM) antagonized the positive inotropic effects of isoprenaline and dobutamine by shifting th...

The ability to form multiple carbon-carbon bonds in a controlled sequence and thus rapidly build molecular complexity in an iterative fashion is an important goal in modern chemical synthesis. In recent times, transition-metal-catalysed coupling reactions have dominated in the development of C-C bond forming processes. A desire to reduce the reliance on precious metals and a need to obtain prod...

The details of the first syntheses of the unusual bis-oxazole natural products siphonazole and its O-methyl derivative are reported. The cinnamyl substituted oxazole was constructed using diazocarbonyl chemistry, whereby the cinnamamide was reacted with the rhodium carbene derived from methyl 2-diazo-3-oxobutanoate to give a beta-ketoamide that was cyclodehydrated to the corresponding oxazole-4...

Metal-diazo radicals of α-carbonyl diazomethanes are new members of the radical family and are precursors to metal-carbene radicals. Herein, using electron paramagnetic resonance spectroscopy with spin-trapping, we detect diazo radicals of α-carbonyl diazomethanes, induced by [Rh(I)Cl(cod)]2, [Co(II)(por)] and PdCl2, at room temperature. The unique quintet signal of the Rh-diazo radical was obs...

Water-soluble phosphanes were tagged with a light-responding diazo group. Upon UV exposure, the diazo-isomerisation led to phosphane morphology change, resulting in an increase in the reaction rate of an aqueous palladium-catalysed cleavage reaction.

Diazo(trimethylsilyl)methylmagnesium bromide readily reacted with various ketones and aldehydes to give the corresponding 2-diazo-(2-trimethylsilyl)ethanols. These were efficiently converted to indazoles bearing hydroxymethyl units at the 3-position by intermolecular [3 + 2] cycloaddition with benzynes.

Diazo compounds, which can be accessed directly from azides by deimidogenation, are shown to be extremely versatile dipoles in 1,3-dipolar cycloaddition reactions with a cyclooctyne. The reactivity of a diazo compound can be much greater or much less than its azide analog, and is enhanced markedly in polar-protic solvents. These reactivities are predictable from frontier molecular orbital energ...

We describe an improved method for the quantitation of total and direct bilirubin in serum in which sodium dodecyl sulfate is used as an accelerator. Viscous and caustic reagents are not needed, and the effects of protein matrix, hemoglobin interference, and turbidity are minimized. For total bilirubin determination we first add the sodium dodecyl sulfate reagent to serum, then a diazo reagent ...