Biotransformation of Organic Sulfides. Part 7. Formation of Chiral Isothiocyanato Sulfoxides and Related Compounds by Microbial Biotransformation.

Abstract The fungi Helminthosporium species NRRL 4671 and Mortierella isabellina ATCC 42613 have been used for the biotransformation of a series of isothiocyanatoalkyl methyl sulfides and their synthetic precursors, ω-(methylthio)alkylphthalimides. H . species gave predominantly ( S ) sulfoxides in all cases; M. isabellina gave ( R ) isothiocyanatoalkyl methyl sulfoxides, but in the case of two ω-(methylthio)alkylphthalimides substantial conversion of sulfoxide to sulfone resulted in the isolation of the former with predominat ( S ) configuration. A correction is made of the previously reported configurations of two biotransformation products (Tetrahedron: Asymmetry, 1994 , 5 , 1129).