The use of a compound of formula Iwherein Y is a single bond, C═O, C═S or S(O)m where m is 0, 1 or 2the ringis a 6-membered aromatic or is a 5 or 6 membered heteroaromatic ring Ra, R1, R2, R4 and R8 are specified organic groups n and p are independently 0-4 or salts or N-oxides thereof or compositions containing them in controlling insects, acarines, nematodes or molluscs. Novel compounds are also provided.