PURPOSE: To obtain a new physiologically active substance epostatin effective for strongly inhibiting dipeptidyl peptidase II and exhibiting immunity regulating action in autoimmune diseases by culturing a specific microbial strain belonging to the genus Streptomyces.
CONSTITUTION: An epostatin-producing strain (FERM P-14068) belonging to the genus Streptomyces is cultured (e.g. by submerged nutrient culture at about 26-30°C for 1-10 days) and the compound of formula is separated from the cultured product. The compound has the following physical and chemical properties. Color and nature, a powdery amphoteric substance having pale yellow color; molecular formula, C23H33N3O5; molecular weight, 431; melting point, 157-159°C (decomposition); specific rotation, [α]23D=-174° (Cl, ethanol); solubility, soluble in dimethyl sulfoxide and methanol and scarcely soluble in ethyl acetate and water; Rf value of thin-layer chromatography, 0.16 (silica gel thin layer: developing solvent is a chloroform : methanol : water mixture at mixing ratios of 65:25:4); etc.
AOYANAGI TAKAAKI
HAMADA MASA
OSANAWA HIROSHI
AKIYAMA TETSUO
