Bu-2313, a new antibiotic complex active against anaerobes. I. Production, isolation and properties of Bu-2313 A and B.

Abstract
An unidentified oligosporic actinomycete strain, No. E864-61, produced 2 new antibiotics, Bu-2313 A (C27H35NO9) and Bu-2313 B (C26H33NO9). Bu-2313 A and B each exhibited a broad antibiotic spectrum against gram-positive and gram-negative anaerobic bacteria, and showed in vivo activity against experimental infections produced by Bacteroides fragilis and Clostridium perfringens. Bu-2313 also inhibited some aerobic bacteria such as streptococci. Bu-2313 B was approximately 2-fold more active than Bu-2313 A.