To obtain the subject compound useful for treating osteoporosis, lowering serum cholesterol, etc. by culturing Streptomyces species A93,017 or its glucuronide variant in a medium containing a specific substituted benzoylbenzothiophene.

Streptomyces species A93,017 or its glucuronide variant is cultured in a nutrient medium containing an assimilable carbon source, nitrogen source, an inorganic salt and a substrate compound composed of 6-hydroxy-2-(4- hydroxyphenyl)-3-[4-(2-piperidinoethoxy)benzoyl]benzo[b]thiophene of formula I under aerobic conditions in a liquid, the culture solution is centrifuged, a supernatant liquid is concentrated under reduced pressure, passed through a nonionic acid adsorption resin, adsorbed and eluted by the linear gradient of methanol-ammonium acetate. The eluted solution is purified by silica gel chromatography to give the objective compound of formula II (R1 and R2 are each H or a β-glucuronide group of formula III).