Nitromethylene analogues of imidacloprid and divalent and oxabridged heterocyclic neonicotinoid compounds constructed by dialdehydes, preparation methods and uses thereof are disclosed. Compounds represented by formula (A) or (B), their optical isomers or agrochemically acceptable salts are provided. Agrochemical compositions comprising the said compounds, their optical isomers or agrochemically acceptable salts, the uses of the said agrochemical compositions and the preparation methods of the said compounds, their optical isomers or agrochemically acceptable salts are also disclosed. The compounds and their derivatives have high insecticidal activities to several farming and forestry pests including homoptera and lepidoptera pests, such as aphis, fulgorid, whitefly, leafhopper, common thrips, cotton bollworm, cabbage caterpillar, cabbage moth, cotton leafworm and armyworm.
