Definition: A group of ANTI-BACTERIAL AGENTS characterized by a chromophoric naphthohydroquinone group spanned by an aliphatic bridge not previously found in other known ANTI-BACTERIAL AGENTS. They have been isolated from fermentation broths of Streptomyces mediterranei.
KRM 1648 [ 3'-hydroxy-5'-(4-isobutylpiperazinyl)benzoxazinorifamycin,ABI 1648,ABI-1648,ABI1648,KRM-1648,benzoxazinorifamycin,rifalazil ] structure in first source