13-EPI-AVERMECTIN DERIVATIVES USEFUL AS ANTIPARASITIC AGENTS

摘要

23/DLR19 17910 TITLE OF THE INVENTION 13-EPI-AVERMECTIN DERIVATIVES USEFUL AS ANTIPARASITIC AGENTS There are disclosed avermectin derivatives in which position 13 of the avermectins has been inverted from the normal (alpha) stereochemistry to the epimeric 13-beta stereochemistry. The synthetic 13-epi analogs are derived from the corresponding aglycones which in turn are prepared by chemical modification of naturally occurring avermectins. The compounds are active antiparasitic agents and compositions for that use are disclosed.