| 摘要 |
<p>NEW MATERIAL:A compound of formulaI[R1 and R2 are H or lower alkanoyl; R3 is (cyclo)alkyl, aryl, aralkyl, monofunctional 4- - 7-membered heterocyclic ring containing 1-4 N, O or S atoms, -R4 or -ZR5; R4 is (OH, lower alkanoyloxy substituted) lower alkylene; R5 is R2 except R4; Y is CO, SO2, CONH, etc.]. EXAMPLE:4''-IsovalerylYT-3927. USE:An antimicrobial agent against pathogenic germs of Gram-positive and Gram- negative bacteria, fungi of the genus Mycoplasma, etc. PROCESS:Streptomyces fradiae YT-3927 strain (FERM-P No.5758 or FERM BP- 12) is cultivated to isolate an antibiotic substance YT-3927. The OH group at the 2'-position is then protected by acetyl group, etc. and then the antibiotic substance YT-3927 is reacted with a reactive derivative of an acid of formula II, e.g. isovaleric acid anhydride, to introduce the group R3-Y- into the OH at the 4''-position, and the protecting group is then removed to give the exemplified compound.</p> |
