The nemadectins are fermentation products of Streptomyces
cyaneogriseus noncyanogenus. Structurally, the
nemadectins lack a disaccharide group at C-13 but differ
from the milbemycins proper because they contain a
trisubstituted double bond at C-26 in their side chains.
Nemadectin is the dominant member of a class of milbemycins bearing unsaturated longer chain groups at the 25-position. Nemadectin shows pronounced nematocidal and insecticidal activity. Nemadectin is the starting material for moxidectin, a commercial anthelmintic.
Nemadectin is a potent antiparasitic macrolide lactone.
