Compounds are described of formula (I) and salts thereof, wherein R<1> represents a methyl, ethyl or isopropyl group; R<2> is alkyl; alkyl substituted by carboxy or alkoxycarbonyl; alkenyl; phenyl or phenalkyl; R<3> is-OH; OR<4> is a hydroxyl group or a substituted hydroxyl group having up to 25 carbon atoms. These compounds may be used for controlling insect, acarine, nematode or other pests.
