Avermectin degradation products and derivatives

Abstract From the Canadian patent

Novel avermectin derivatives are disclosed wherein the C-17-21-25-dioxaspirane substructure has been disassembled and modified to include oxygen substitution at C-24 and C-25 and examples of C-24 and C-25 substituents are hydrogen, alkyl alkenyl, substituted alkyl or substituted alkenyl groups. These compounds can be further substituted at the 4"-, 5-, 13-, and 23- positions. The new C-24 and C-25 substituted avermectin derivatives are prepared by cleavage of known and suitably protected avermectin compounds. The new compounds are potent anti-parasitic agents, in particular, the compounds are anthelmintic, insecticidal and acaricidal agents.