Synthesized Of C Ring Diffierent Configuration And Heterocyclic Ring Substituted Of Podophyllotoxin And Their Antifeedant Activities

Aiming to study the insecticidal activity , 28 podophyllotoxin derivatives were synthesized based on earlier stage work .Their chemical structure were confirmed by IR,MS,1H-NMR and 13C-NMR.And another 3 podophyllotoxin analogues were collected. The antifeedant activities of 31 compounds against the 3rd-instar larvae of Mythimna separataduring 24h and 48h were assayed with leaf-disk method. The results showed as follows:1. Among the 28 synthesized compounds ,18 compounds which contained heterocyclic ring were new compounds .2. The C4 contained heterocyclic ring of podophyllotoxin derivatives can get higher antifeedant activity than podophyllotoxin . The 24h AFC50(concentration for 50% antifeedant activity) against the 3rd larvae of Mythimna separata of 4α-1H-indole-3-acetic acid-4- deoxy- podophyllotoxin ether (I4) was 0.36mg·ml-1 which was 1/2.06 of podophyllotoxin .And the others had lower activity than podophyllotoxin .3. The antifeedant activity of those compounds which 4βcontained ether bond with heterocyclic ring were the highest in the 18 compounds contained heterocyclic ring.4. The antifeedant activities ofα-Apopicropodophyllin was the only one higher than podophyllotoxin in all of synthesized compounds against the 3rd-instar Mythimna separata during both 24h and 48h. Its 24h and 48h AFC50 against the 3rd larvae of Mythimna separata was respectively 1/1.30 and 1/2.70 of podophyllotoxin. The 24h antifeedant activities ofβ-Apopicropodophyllin was equal to that of podophyllotoxin against the 3rd-instar Mythimna separata ,but 48h AFC50 was 1/1.78 of podophyllotoxin. The results showed that: not saturation of C ring of podophyllotoxin analogues had very higher activities than others.5. The antifeedant activities of compounds which had different configuration of C4 and C2 were assayed against the 3rd-instar Mythimna separata .The result showed that: (1) The activity of C4α-configuration podophyllotoxin derivatives were higher than theirβ-configuration analogues (2) The activity of C2β-configuration podophyllotoxin derivatives were higher than theirα-configuration derivatives.