During the past years, the topic sensitive skin became one of the most important fields in dermatology. The tremendous interest is based on several studies showing that about 50% of the population declares to have sensitive skin. The human thermoreceptor hTRPV1 was previously identified to contribute to this skin condition while facilitating neurogenic inflammation leading to hyperalgesia. Furthermore, skin sensitivity towards capsaicin, a natural activator of TRPV1, was shown to correlate with sensitive skin. In a screening campaign based on recombinant HEK293-cells stably transfected with hTRPV1, the selective antagonist trans-4-tert-butylcyclohexanol was identified. This antagonist is able to inhibit capsaicin-induced hTRPV1 activation with an IC(50) value of 34 ± 5 μm tested in HEK293-cells as well as in electrophysiological recordings performed in oocytes expressing hTRPV1. Strikingly, in a clinical study with 30 women using topical treatment with o/w emulsions containing 31.6 ppm capsaicin, we were able to show that 0.4% of this inhibitor significantly reduces capsaicin-induced burning (P < 0.0001) in vivo. Thus trans-4-tert-butylcyclohexanol has the potential as a novel bioactive for the treatment of sensitive skin.

As part of our studies of metal-catalyzed [m + n (+...o)] cycloadditions, we have previously reported the rhodium-catalyzed [5 + 2] cycloaddition of vinylcyclopropanes (VCPs) and pi-systems. These studies have led to Rh(I) complexes that catalyze these reactions in minutes at room temperature or in water without organic solvents. We describe a comparative evaluation of several chiral catalysts for the [5 + 2] reaction, evaluation of a preferred catalyst, [((R)-BINAP)Rh]+SbF6-, with substrates differing in substitution and tether types-producing enantiomeric excesses >/=95% for several systems. A predictive model for the selectivity is also presented.

[reaction: see text] A highly convergent asymmetric synthesis of the masked southern segment of the antimitotic agent disorazole A(1) involves a Sonogashira coupling between a C1'-C10' enyne and a suitably protected C11'-C19' vinyl iodide. The central E,Z,Z-triene moiety is masked as a more stable ynediene.

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How do the boiling points of substances vary with pressure? Commonly used nomographs can give a misleading impression of accuracy. An applet is presented which gives a more precise measure of the uncertainty in the calculation, whilst giving a straightforward way to calculate how boiling points may vary with pressure. Related applets calculate Boltzmann factors and the solution to the Eyring equation, which give an idea of how rate and selectivity may change with temperature.