The incorporation of oxygen containing groups into the steroid structure is of considerable interest in connection with the synthesis of corticosteroids and cardioactive substances. Oxidations with reagents containing hexavalent chromium have been widely used either to functionalize non-activated positions of policyclic hydro­ carbons [1 ], or to obtain through allylic oxidations keto derivativ...

During the course of the transformation of 1,3-dichloro-2-propanol (DCP) into (R)-3-chloro-1,2-propanediol [(R)-MCP] with the cell extract of Corynebacterium sp. strain N-1074, epichlorohydrin (ECH) was transiently formed. The cell extract was fractionated into two DCP-dechlorinating activities (fractions Ia and Ib) and two ECH-hydrolyzing activities (fractions IIa and IIb) by TSKgel DEAE-5PW c...

The regioselective opening of epoxides with organotin oxides 1 and 2, in presence of halogenated alcohols was developed, yielding the halohydrin derivatives. Introduction Epoxides are among the most versatile intermediates in organic chemistry due to the particular polarity and strength of their three member ring. Those characteristics make them in a very suitable substrate to the attack or man...

Cyclic carbonates are considered to be green nontoxic intermediates with important applications in polymer synthesis and fuel additives as polar solvents high boiling points. The carbonation of epoxidized vegetable oils is a very step the nonisocyanate polyurethane. This reaction usually performed carbon dioxide presence an ionic liquid that acts both solvent catalyst, most studied catalyst bei...

The regioselective ring opening of styrene oxide using elemental iodine and bromine in the presence of disulfides as new catalysts was studied. The conductivity titration and UV spectroscopy were used to study the interaction of iodine with these catalysts. The results indicate that disulfide 11 is efficient in polyiodide formation, and can catalyze this reaction in excellent yield and high reg...

The regioselective ring opening of styrene oxide using elemental iodine and bromine in the presence of disulfides as new catalysts was studied. The conductivity titration and UV spectroscopy were used to study the interaction of iodine with these catalysts. The results indicate that disulfide 11 is efficient in polyiodide formation, and can catalyze this reaction in excellent yield and high reg...

Halohydrin dehalogenases, also known as haloalcohol dehalogenases or halohydrin hydrogen-halide lyases, catalyze the nucleophilic displacement of a halogen by a vicinal hydroxyl function in halohydrins to yield epoxides. Three novel bacterial genes encoding halohydrin dehalogenases were cloned and expressed in Escherichia coli, and the enzymes were shown to display remarkable differences in sub...