title: Larvicidal activity of synthetic tropane alkaloids against Ascia monuste orseis (Lepidoptera: Pieridae).
abstract: BACKGROUND
  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.
  
  
  RESULTS
  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 LD50values of 1.01, 3.76 and 1.92 µg substance mg-1insect, and TL50values 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.
  
  
  CONCLUSIONS
  Tropane alkaloid derivatives bearing a carbamate group show potential for the development of novel insecticides against A. monuste. © 2017 Society of Chemical Industry.
authors.affiliation: Department of Chemistry, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Simone Z
authors.initials: SZ
authors.lastname: Mairink
authors.affiliation: Department of Chemistry, Universidade Federal de Viçosa, Viçosa, MG, Brazil.|Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Luiz Ca
authors.initials: LC
authors.lastname: Barbosa
authors.affiliation: Department of Chemistry, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Eduardo Vv
authors.initials: EV
authors.lastname: Varejão
authors.affiliation: Department of Animal Biology, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Elizeu S
authors.initials: ES
authors.lastname: Farias
authors.affiliation: Department of Animal Biology, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Márcio Lm
authors.initials: ML
authors.lastname: Santos
authors.affiliation: Department of Animal Biology, Universidade Federal de Viçosa, Viçosa, MG, Brazil.
authors.forename: Marcelo C
authors.initials: MC
authors.lastname: Picanço
mesh_terms: D000818:Animals; D001681:Biological Assay; D002080:Butterflies / Q000254:growth & development; D007300:Insect Control; D007306:Insecticides; D007814:Larva / Q000254:growth & development; D014326:Tropanes / Q000138:chemical synthesis
chemical_list: D007306:Insecticides; D014326:Tropanes
keywords: Ascia monuste; Solenopsis saevissima; Tetragonisca angustula; carbamate; insecticide activity; tropane alkaloids