| abstract |
Compounds of formula (I), wherein X1 and X5 are each separately selected from hydrogen and C1-4 alkyl, halogeno and halogeno-substituted C1-4 alkyl groups: X2, X3 and X4 are each separately selected from hydrogen and C1-4 alkyl, hydroxy, C1-4 alkoxy and phenoxy groups; R1 and R2 are each separately selected from hydrogen and C1-4 alkyl groups; R3 and R4 are each hydrogen or together constitute the second bond of a carbon-carbon double bond joining -CR1R3 and -CR2R4; and Y is hydroxymethyl, formyl, cyano, carbamoyl, carbamoyl N-substituted by one or two of the same or different C1-4 alkyl groups, carboxy or a carboxylic ester or carboxylate salt, are of value as avian repellents. |