| abstract |
NEW MATERIAL:A compound of formula I [R 1 , R 2 are H, lower alkanoyl; R 3 is H, -COCH 3 R 5 (R 5 is lower alkyl, pyridinyl); R 4 is aryl, pyridinyl, aryl, nitrile; A is -OCO-, -OSO 2 -, -O-, -S-, A and R 4 incorporate to represent halogen or nitrile]. n USE: Antibacterial: it shows high activity against gram-positive and -negative bacteria and mycoplasmas. n PREPARATION: For example, Streptomyces fradiae YO-9010 strain (ATCC 31846) is cultured and antibiotic YO-9010 of formula II is separated from the culture mixture. Then, the purified product is brominated in the 23-position by adding carbon dibromide thereto in pyridine in the presence of triphenylphosphine or acylated with, e.g., acetic anhydride, to introduce a lower alkanoyl group to give the compound of formula I . n COPYRIGHT: (C)1983,JPO&Japio |