A novel macrocyclic lactone with insecticidal bioactivity from Streptomycesmicroflavus neau3

A novel macrocyclic lactone (1) was isolated from the fermentation broth of Streptomycesmicroflavus neau3, and the structure was elucidated by extensive spectroscopic analysis. Compound 1 showed high acaricidal activity against adult mites (IC50 = 11.1 μg mL−1), and nematocidal activity against Caenorhabditis elegans (IC50 = 17.4 μg mL−1), especially the acaricidal activity against mite eggs with an IC50 of 37.1 μg mL−1, which was relative higher than that of the commercial acaricide and nematocide milbemycins A3/A4.