| 摘要 |
23,Demycinosyloxytylosin and its 20-dihydro deriv. of formula (I) (where Q is CHO or CH2-OH, respectively) and their acyl esters, and their acid-addn. salts are new. Streptomyces fradiae NRRl 12171 is new. A culture medium contg. Strep.fradiae NRRL 12171 and assimilable sources of C, N and inorganic salts is new. (I) are antimicrobials esp. effective against Gram-positive bacteria and Mycoplasma spp., e.g. in poultry. Cpds. (I) are obtd. by cultivation under submerged aerobic conditions of Strep.fradiae NRRL 12171 in a nutrient medium. The (I; Q is CHO) may be reduced to give (I; Q is CH2-OH). On mild acid hydrolysis (I) give 23-deoxy-5-0- mycaminosyltylonolide or its 20-dihydro deriv. Cpds. (I) may be acylated, selectively or fully, by known methods. NRRL 12171 was obtd. by chemical mutagenesis of a tylosin- producing strain of Strep.fradiae. |
