Sarubicin b, a new quinone antibiotic, isolated from the fermentation broth of a streptomyces strain

Sarubicin B, isolated from the culture filtrate of a Streptomyces strain JA 2861, is a new quinone Antibiotic. The compound was isolated as an orange crystalline powder, mp 282 approximately 284 degrees C. In vitro sarubicin B was found to inhibit Gram-positive bacteria. It was not active against Gram-negative Microorganisms.