ANTIBIOTIC A51568 FACTOR A AND B,THEIR METHOD OF PREPARATION AND PHARMACEUTICAL COMPOSITION

摘要

There are disclosed antibiotics of formula wherein n is 1 or 2, or a pharmaceutically acceptable salt thereof, or an antibiotic mixture comprising an antibiotic of formula (I) or a pharmaceutically acceptable salt thereof as the major component. Antibiotic A51568 factors A and B are produced by submerged, aerobic fermentation of Nocardia orientalis NRRL 15232. The antibiotic is gram-positive.