Avermectin derivatives

摘要

Provided is a compound represented by the general formula (I) or a salt thereof: wherein, -XY- represents -CH-CH- and the like, between R² and the carbon atom at 5-position represents a single bond or a double bond, R¹ represents a lower alkyl group, a formyl group, a carboxyl group, a lower alkoxycarbonyl group (wherein a lower alkyl moiety of said lower alkoxycarbonyl group may be substituted with a heterocyclic group) and the like, and R^1a represents a hydrogen atom, provided when R¹ represents a lower alkoxycarbonyl group and the like, R^1a may further represents a lower alkoxycarbonyl group and the like, when between R² and the carbon atom at 5-position is a single bond, R² represents a hydroxyl group and the like, and when between R² and the carbon atom at the 5-position is a double bound, R² combines with the carbon atom at 5-position to form a hydroxime group (-C(-NOH)) and the like, and R³ represents a hydroxyl group or a tri(lower alkyl)silyloxy group.