Compounds and compositions containing them, for insecticidal control having the formula ##STR1## in which R.sub.1 is an alkyl group having from 1 to 3 carbon atoms, R.sub.2 is an alkyl group having from 1 to 6 carbon atoms, and R.sub.3 and R.sub.4 are independently alkyl groups having from 1 to 6 carbon atoms, or R.sub.3 and R.sub.4 taken together form a ring having the formula ##STR2## in which m and n are each integers from 1 to 3 and X is oxygen or --CH.sub.2 --, together with insecticidal compositions containing such compounds, and methods for controlling insects.