Valiolamine derivatives and production thereof

摘要

A novel valiolamine derivative of the formula (I): <IMAGE> (I) where R stands for hydrogen or beta -D-glucopyranosyl group is useful for a starting material of valiolamine which can be converted to more potent alpha -glucosidase inhibiting compounds. The valiolamine derivative is obtained by cultivating Streptomyces hygroscopics in a culture medium and recovering the valiolamine derivative produced and accumulated from the culture broth.