Pyraclofos

Preparation of 1-(4-chlorophenyl)-4-hydroxypyrazole. 3-Chloroacetone aldehyde hydrazone-p-chlorobenzene undergoes cyclization reaction in methanol in the presence of sodium hydroxide to produce 1-(4-chloro Phenyl)-4-hydroxypyrazole. Synthesis of pyrazophos 1-(4-chlorophenyl)-4-hydroxypyrazole in the presence of triethylamine, in acetonitrile solution, reacts with O-ethyl-S-propylthiophosphoryl chloride The temperature is 50°C, and the reaction time is 3 hours to prepare pyrazophos.

This product has poor anti-acetylcholinease activity in vitro, but it has good insecticidal activity against Spodoptera litura, and its larval acetylcholinesterase is inhibited by this product. This product shows a higher inhibitory activity on insect fatty esterases (compared to acetylcholinesterase in the nervous system). With contact and stomach toxicity, no systemic activity on the root system. It is effective against a variety of pests such as Lepidoptera, Coleoptera, aphids, Diptera and cockroaches, as well as spider mites, root mites, rickets, ticks and nematodes. Field tests showed that the control objects also include cotton bollworm, red bollworm, coastal armyworm, cotton planthopper, tobacco thrips, potato beetle, potato tuber moth, tea leaf moth, tea yellow thrips, alfalfa leaf weevil, tobacco hawk moth. The dosage is 0.5～1.5kg (active ingredient)/hm2. It has slight phytotoxicity to apple, citrus, Japanese pear and other fruit trees, which varies with the varieties.