Bioactivity of several podophyllotoxin analogues

Objective: The bioactivity of four podophyllotoxin analogues were tested against 3rd instar larvae of Culex pipiens pallens and 5 h instar larvae of Pieris rapae L.Methods:WHO bioassay and leaf-dlpping method. Results: ①Deoxypodophyllotoxin and β-apopicropodophyllotoxin exhibited toxicity(against) Culex pipiens pallens,and their LC_(50) were 0.001 48 and 0.001 68 g/L,respectively.②All the four podophyllotoxin analogues displayed inhibitory effect on the growth and development against Culex pipiens pallens,their pupation rates were delayed comparing with control.③Deoxypodophyllotoxin,β-apopicropodophyllotoxin and Podophyllotoxin exhibited toxicity against Pieris rapae L,the LC_(50) 96 h after treatment were 0.045 4?0.078 2 and 0.159 7 g/L,respectively.④All the four podophyllotoxin analogues showed antifeedant activity against Pieris rapae L,their AFC_(50)were 0.016 1,0.018 7,0.039 4 and(0.273 9) g /L,respectively.⑤All four podophyllotoxin analogues displayed inhibitory effect on the growth and development against Pieris rapae L,but the extent of each compound were very different. Conclusion: Based on the data obtained in this investigation,it is possible that the dissimilarity in the structure of the analogues leads to their different bioactivity.