Nitro-substituted heterocyclic compounds of the formula (I) ##STR1## wherein R is hydrogen or alkyl, Z is an optionally substituted aryl or optionally substituted heterocyclic group containing at least one atom selected from N, O and S, A is optionally substituted ethylene or optionally substituted trimethylene, and B stands for 2 or 3 members of a heterocyclic ring which is formed, together with the adjacent C-atom and N-atom and at least one of said members may represent a hetero atom and may be optionally substituted, provided that when B stands for 3 members, two of which are carbon atoms and the other one is a nitrogen atom which is located in the middle of the three members, then at least one of said two carbon atoms must be substituted by a keto group. Such compounds being useful as insecticides.
This is a division of application Ser. No. 07/998,337, filed Dec. 30, 1992, now U.S. Pat. No. 5,290,779, which is a division of Ser. No. 07/823,240, filed Jan. 21, 1992, now U.S. Pat. No. 5,231,098, which is a division of Ser. No. 699,068, filed May 13, 1991, now U.S. Pat. No. 5,122,527, which is a division of application Ser. No. 510,509, filed Apr. 18, 1990, now U.S. Pat. No. 5,036,082, which is a division of application Ser. No. 353,370, filed May 17, 1989, now U.S. Pat. No. 4,960,780, which is a division of application Ser. No. 208,421, filed Jun. 17, 1988, now U.S. Pat. No. 4,876,263.
