Artigo Acesso aberto Produção Nacional Revisado por pares

Larvicidal activity of synthetic tropane alkaloids against Ascia monuste orseis (Lepidoptera: Pieridae)

2017; Wiley; Volume: 73; Issue: 10 Linguagem: Inglês

10.1002/ps.4565

ISSN

1526-4998

Autores

Simone Z. Mairink, Luiz C. A. Barbosa, Eduardo Vinícius Vieira Varejão, Elizeu S. Farias, Márcio LM Santos, Marcelo C. Picanço,

Tópico(s)

Allelopathy and phytotoxic interactions

Resumo

Tropane alkaloids are known to play a role in plant defence. By blocking acetylcholine receptors, they exert insecticidal and deterrent effects against herbivore insects. Carbamates are an important class of chemical insecticides that also inhibit acetyl cholinesterase. The objective of this work was to synthesise a series of tropane alkaloids bearing a carbamate group, and to evaluate their effects against the pest Ascia monuste. The effects of the most active compounds were evaluated on the A. monuste predator Solenopsis saevissima and on the pollinator Tetragonisca angustula.The synthesis of carbamate-tropane alkaloids was accomplished in 4-5 steps from commercially available ketones. Results from bioassays showed that compounds 6a, 10a and 14a presented higher activities against second-instar larvae of A. monuste, with LD50 values of 1.01, 3.76 and 1.92 µg substance mg-1 insect, and TL50 values of 7.0, 15.0 and 5.0 h respectively. These compounds were also tested for their selectivity in favour of S. saevissima and T. angustula. Compound 6a, which showed the highest activity against A. monuste, also showed lower toxicity against S. saevissima.Tropane alkaloid derivatives bearing a carbamate group show potential for the development of novel insecticides against A. monuste. © 2017 Society of Chemical Industry.

Referência(s)