| 摘要 |
NEW MATERIAL:A deacylated antibiotic of formula I: (R1 is H, acetyl, or propionyl group) and its salt. EXAMPLE:Isoleucomycin V(R1 is H in the formula I). USE:A starting material for 13-acyl antibiotics, capable of giving the 13-acyl antibiotics having a good antibacterial spectrum and concentration in the blood free from bitterness by acylating OH groups at the 13- and 4''-positions of the compound of formula I. PROCESS:Esterase-producing bacteria, e.g. Nocardia sp., FERM-P No. 2019, which fall under the genus Nocardia or Stuphylotrichum, are cultured in a liquid medium at 27-32 deg.C for 2-5 days, and the cultured or treated product is reacted with an autibiotic of formula II: (R2 is acetyl, propionyl, butyryl, or isovaleryl group) in an aqueous solution at pH7-10, preferably 9, at 37 deg.C for 30 min - 3 days to decompose the ester group at the 4''-position, and the fittrate is extracted with benzene to give the compound of formula I. |
