In view of the possible role of electron transfer in biology and medicine, and wide distribution of polyenes in living nature, we consider the electron transfer mechanism of geometrical cis-trans isomerization as an important route which can play a key role in many photochemical and biological processes. The various mechanisms of geometrical cis-trans isomerization mediated by electron transfer...

The isomerization of spiropyrans in crystals was realized under high pressure, and the corresponding mechanochromic response could be observed by the naked eye. In situ UV-Vis spectroscopy study demonstrated that the equilibrium constant increases with the increasing pressure, from which we proposed that the negative volume of reaction determined the isomerization under high pressure.

Iridium complexes of novel NCP pincer ligands containing pyridine and phosphinite arms have been synthesized. One Ir complex shows good catalytic activity for alkane dehydrogenation, and all complexes are highly active for olefin isomerization. A combination of the Ir complex and a (PNN)Fe pincer complex catalyzes the formation of linear alkylboronates selectively from internal olefins via sequ...

Stopped-flow experiments obtained in the pre-steady-state time scale of the NAD-malic enzyme reaction exhibit a lag prior to the attainment of steady state. Previous results from isotope effect studies in which the deuterium isotope effect on Vmax decreases to a value of 1 at low pH have been interpreted as suggesting a slow release of NADH [Kiick, D. M., Harris, B. G., & Cook, P. F. (1986) Bio...

The title compound, C(16)H(18)F(6)O(4), was obtained through an unprecedented one-pot reaction sequence involving a Gosteli-Claisen rearrangement and a cyclo-isomerization. The constitution and relative configuration were determined by single-crystal X-ray diffraction analysis. In the crystal, mol-ecules are connected via O-H ⋯ O hydrogen bonds.

Low dark noise is a prerequisite for rod cells, which mediate our dim-light vision. The low dark noise is achieved by the extremely stable character of the rod visual pigment, rhodopsin, which evolved from less stable cone visual pigments. We have developed a biochemical method to quickly evaluate the thermal activation rate of visual pigments. Using an isomerization locked chromophore, we conf...

The nearest neighbor level spacing and D3 distributions indicate that the vibrational spectrum of CH2ð~aA1Þ is largely chaotic. Nevertheless, regular localized states coexist with the chaotic ones and they are related to overtone states of the principal vibrational modes. Periodic orbits accompanied by a stability analysis identify these states and explain their topologies and localization in c...

We address here the manner in which acid catalysis senses the strength of solid acids. Acid strengths for Keggin polyoxometalate (POM) clusters and zeolites, chosen because of their accurately known structures, are described rigorously by their deprotonation energies (DPE). Mechanistic interpretations of the measured dynamics of alkane isomerization and alkanol dehydration are used to obtain ra...

In retinal rods, light-induced isomerization of 11-cis-retinal to all-trans-retinal within rhodopsin triggers an enzyme cascade that lowers the concentration of cGMP. Consequently, cyclic nucleotide-gated (CNG) ion channels close, generating the first electrical response to light. After isomerization, all-trans-retinal dissociates from rhodopsin. We now show that all-trans-retinal directly and ...