Design, synthesis and insecticidal activity of novel semicarbazones and thiosemicarbazones derived from chalcone

Thirty semicarbazone and thiosemicarbazone derivatives (2a-w and 4a-g) from chalcones containing furan and thiophene ring were designed and synthesized. They were characterized by IR, H-1 NMR, C-13 NMR and HRMS. The crystal structure of compound 2r was characterized by single crystal X-ray diffraction. It crystallizes in the monoclinic system with space group P2(1)/c. The insecticidal activity of the synthesized compounds was screened against Leucania separata and Pieris rapae using beta-cypermethrin as the comparative standard. The results displayed that most of them had remarkable insecticidal activity. Among them, compounds 2e-g showed better activity than beta-cypermethrin against L. separata and P. rapae. Compound 2p also possessed a better activity than beta-cypermethrin against P. rapae. The insecticidal activities of these compounds have been reported for the first time.

Automated summary

A series of thirty semicarbazone and thiosemicarbazone derivatives designed with furan and thiophene ring-containing chalcones showed remarkable insecticidal activity, with compounds 2e-g exhibiting better efficacy than the comparative standard beta-cypermethrin against Leucania separata and Pieris rapae. These compounds, including 2p, displayed significant insecticidal activity against the two insect species for the first time.