NEW MATERIAL:Antibiotic substance KA-6643-D of formulaI, antibiotic substance KA-6643-F of formula II, their salts or their esters.
USE: Antimicrobial agent effective to Gram-positive and Gram-negative bacteria, and having strong β-lactamase-inhibiting activity.
PROCESS: Streptomyces KC-6643 strain (FERM-P No.4467) is cultured in a liquid medium under aerobic conditions, and the filtrate of the cultured medium is passed through e.g. a basic anion-exchange resin to adsorb the group of KA-6643 substances, which are eluted with a salt solution, etc. The eluate is passed through a strongly basic ion exchange resin to adsorb the group of KA-6643 substances. The KA-6643-A, -B, -D and -F-substances are eluted successively by passing a phosphate bubber solution through the ion exchange resin gradually changing the concentration of sodium chloride in the solution. By further purification and separation, the objective KA-6643-D and -F substances can be obtained.
NAKAYAMA MASATO
IWASAKI AKIO
KIMURA SHIGERU
MIZOGUCHI TOSHIMI
TANABE SOUHEI
MURAKAMI AKIRA
ITOU HISAKATSU
MORI TOSHITO
