Site-directed mutagenesis was used to identify key amino acid residues of the cholesterol oxidase from Streptomyces sp., which catalyzes the oxidation of cholesterol and the isomerization of 5-cholesten-3-one. Eight mutant enzymes were constructed and the following amino acid substitutions were identified: N318A, N318H, E356A, E356D, H441A, H441N, N480A and N480Q. Mutants N318A and N318H retain...

Isomerization-linear-hydroformylation is demanding, however, not an addressed issue, for the production of value-added linear aldehydes by converting cheap and abundant internal alkenes available from bio- & petrochemical industry. In this paper, a dual metal catalysis system combining Ru-isomerization catalyst Rh-linear-hydroformylation satisfying “4S” criterions was reported isomerization-lin...

With latest improvements in MEMS, combustion based Micro-Power generation devices are seen as alternatives for conventional batteries because of the high energy densities of Hydrogen and other hydrocarbon fuels. An important feature of micro-power system is to utilize the combustion of fuel or propellant in the micro-burner to produce the gas with high temperature and high pressure to drive tur...

Development of quantitative theory of adsorption-induced deformation is important, e.g., for enhanced coalbed methane recovery by CO2 injection. It is also promising for the interpretation of experimental measurements of elastic properties of porous solids. We study deformation of mesoporous silica by n-pentane adsorption. The shape of experimental strain isotherms for this system differs from ...

The first Ni-catalysed alkene isomerization of allylamides for the synthesis of enamides was demonstrated. Various substituted N-allylamides were found to be suitable substrates for this isomerization. Isotopic labelling experiments showed that it is an intramolecular hydrogen transfer process.

Abstract Invited for this month's cover picture is the group of synthetic and physical chemists from Czech Academy Sciences. The shows electrochemical dechlorination polychlorinated derivatives bicyclo[1.1.1]pentane‐1,3‐dicarboxylic acid. Read full text Article at 10.1002/celc.202100372 .

The effect of H2 on isomerization pathways and on the acid site density on WOx-ZrO2 catalysts was explored using kinetic measurements of acid-catalyzed o-xylene isomerization reactions. Initial o-xylene isomerization rates on WOx-ZrO2 at 523 K are proportional to the H2 concentration even though H atoms are not involved directly in reaction turnovers, as shown by the low deuterium content in th...

Photoisomerization of azobenzene derivatives is a versatile tool for devising light-responsive materials for a broad range of applications in photonics, robotics, microfabrication, and biomaterials science. Some applications rely on fast isomerization kinetics, while for others, bistable azobenzenes are preferred. However, solid-state materials where the isomerization kinetics depends on the en...

The conformational isomerization dynamics of melatonin and 5-methoxy N-acetyltryptophan methyl amide (5-methoxy NATMA) have been studied using the methods of IR-UV hole-filling spectroscopy and IR-induced population transfer spectroscopy. Using these techniques, single conformers of melatonin were excited via a well-defined NH stretch fundamental with an IR pump laser. This excess energy was us...