Yukio Morimoto

On the active sites of hydrogenase from desulfovibrio vulgaris miyazaki f

An EXAFS study of hydrogenase solution has been carried out at Ni and Fe K- absorption edge. The presence of Ni atom was confirmed by the observed jump at Ni K-edge, and the ratio of the content of Ni atom and Fe atom was estimated to be 1:15 based on the ratio of the K-edge jump magnitudes. The EXAFS data at Fe K-edge were analyzed by radial distribution function. Both plausible model of Fe4S4 and Fe3S4 clusters could account for the oserved data. It is most probable that the active center of hydrogenase consists of Fe4S4 and Fe3S4 clusters and Ni atom is also included in an enzyme molecule.

Intramolecular hydrogen shift in reduction of β-mercuro ketal. Preparation of optically active sec-tert-1,3-diols

Abstract Intramolecular hydrogen shift of β-radical ketal was found in the reduction of optically active β-mercuro ketal. The addition of olefins to this hydrogen transferred radical proceeded regio and diastereo differentiatingly and afforded optically active sec-tert- 1,3-diols.