| 摘要 |
<p>The fermentation medium of Streptomyces cyanogriseus subsp. noncyanogenus is supplemented with 2-methylbutyric acid in order to prepare the higher analog of the compound normally produced by the microorganism. The microorganism usually produces a 1,3-dimethyl-1-butene side chain at the 25-position of the milbemycin macrocyclic lactone ring. The new analog is the 1,3-dimethyl-1-pentene side chain. The new compound is a potent anthelmintic and acaricidal agent and compositions for such uses are also disclosed.</p> |
