avermectin derivatives and their use for the control of parasitic infections in humans and animals and insect and parasite infections in agriculture and horticulture, and pharmaceutical preparations indeholdenthese derivatives

摘要

Compounds of the formula: CHEM wherein the broken line at the 22-23 position represents an optional double bond and wherein either R1 is H or OH and the double bond is absent, or, the double bond is present and R1 is absent; R2 is =CH2 or a group of the formula -(X)-C(R5)=CHR6; R3 is H or CH3: R5 and R6 are both H; R5 is H and R6 is C1-C3 alkyl; or one of R5 and R6 is H and the other is phenyl, heteroaryl, C2-C6 alkoxycarbonyl or substituted phenyl or heteroaryl wherein said substituent is fluorine, chlorine, C1-C4 alkyl, C1-C4 alkoxy, C1-C4 alkylthio, hydroxy(C1-C4)alkyl, cyano, aminosulphonyl, C2-C6 alkanoyl, C2-C6 alkoxycarbonyl, nitro, trifluoromethyl, trifluoromethoxy, amino or mono or di-C1-C4 alkylamino; and X is a direct bond or is an alkylene group having from 2 to 6 carbon atoms which may be straight or branched-chain; with the proviso that R5 and R6 are not both hydrogen when X is -CH(CH3)CH2-, are broad spectrum antiparasitic agents having utility as anthelmintics, ectoparasiticides, insecticides, acaricides and animal growth promotants.