title: Tetraoxanes as a new class of efficient herbicides comparable with commercial products.
abstract: BACKGROUND
  Several 1,2,4,5-tetraoxanes were synthesised, and their herbicidal activity was tested against weeds and compared with the activity of commercial herbicides glyphosate and imazethapyr.
  
  
  RESULTS
  The compounds were prepared by reacting carbonyl compounds with hydrogen peroxide under acid catalysis, affording 1,1-dihydroperoxides (36-91%) that were further converted into 1,2,4,5-tetraoxanes (10-52%) under similar reaction conditions. All products were evaluated against Sorghum bicolor and Cucumis sativus at 0.0125-1.0 mM, and several tetraoxanes caused >70% inhibition of the growth of roots and aerial parts. The most active products were evaluated against the weeds Sorghum arundinaceum, Euphorbia heterophylla, Brachiaria brizantha and Bidens pilosa. Some compounds were highly effective (>80% inhibition at 1.0 mM) against the weeds, showing activity comparable with that of glyphosate or imazethapyr. One of the tetraoxanes was selective, being inactive against dicotyledonous species while inhibiting the roots and aerial parts of monocotyledonous species by 92.9-97.5%, which is comparable with the effect of glyphosate.
  
  
  CONCLUSIONS
  Tetraoxanes constitute a new class of effective herbicides with great potential for commercial development.
authors.affiliation: Department of Chemistry, Federal University of Viçosa, Viçosa, MG, Brazil.
authors.forename: Raphael C
authors.initials: RC
authors.lastname: Cusati
authors.affiliation: Department of Chemistry, Federal University of Viçosa, Viçosa, MG, Brazil.|Department of Chemistry, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
authors.forename: Luiz C A
authors.initials: LC
authors.lastname: Barbosa
authors.affiliation: Department of Chemistry, Federal University of Viçosa, Viçosa, MG, Brazil.
authors.forename: Célia R A
authors.initials: CR
authors.lastname: Maltha
authors.affiliation: Department of Chemistry, Federal University of Viçosa, Viçosa, MG, Brazil.
authors.forename: Antônio J
authors.initials: AJ
authors.lastname: Demuner
authors.affiliation: Department of Chemistry, University of Los Andes, Mérida, Mérida State, Venezuela.
authors.forename: Alberto
authors.initials: A
authors.lastname: Oliveros-Bastidas
authors.affiliation: Department of Plant Science, Federal University of Viçosa, Viçosa, MG, Brazil.
authors.forename: Antônio A
authors.initials: AA
authors.lastname: Silva
mesh_terms: D018553:Cucumis sativus / Q000187:drug effects; D005998:Glycine / Q000031:analogs & derivatives / Q000494:pharmacology; D006540:Herbicides / Q000138:chemical synthesis* / Q000494:pharmacology; D009539:Nicotinic Acids / Q000494:pharmacology; D063245:Plant Development / Q000187:drug effects; D057685:Plant Weeds / Q000187:drug effects*; D045868:Sorghum / Q000187:drug effects; D045568:Tetraoxanes / Q000138:chemical synthesis* / Q000494:pharmacology; D000097797:Glyphosate
chemical_list: D005998:Glycine; D006540:Herbicides; D009539:Nicotinic Acids; D045568:Tetraoxanes; D000097797:Glyphosate; C093630:imazethapyr
keywords: 1,2,4,5-tetraoxanes; heterocyclic herbicides; peroxides; plant growth regulators; weeds