RESUMEN
2,2'-Thiodiacetic acid derivatives have a wide application potential, mainly in coordination chemistry. This research indicates that quaternary ammonium 2,2'-thiodiacetate salts may also be potent herbicidal agents used in agriculture. To provide a rationale for this statement, the toxic effect by a alkyl and aryl quaternary ammonium salts (QASs) on plant growth was investigated. The phytotoxicity of these compounds was tested against cultivated monocotyledonous (spring barley) and dicotyledonous (common radish) plants, whereas herbicidal activity was investigated in relation to popular weeds species (white goosefoot, sorrel and gallant-soldier). The results showed that aliphatic QASs possessed a low phytotoxicity to food crops and that some of them (in particular triethylammonium salt) had potent and selective herbicidal properties against common weeds, such as sorrel and gallant-soldier. However, the investigated compounds appeared to be ineffective herbicides against white goosefoot.
Asunto(s)
Herbicidas/toxicidad , Malezas/efectos de los fármacos , Compuestos de Amonio Cuaternario/toxicidad , Tioglicolatos/toxicidad , Compuestos de Amonio , Asteraceae/efectos de los fármacos , Chenopodium album/efectos de los fármacos , Herbicidas/química , Hordeum/efectos de los fármacos , Hordeum/crecimiento & desarrollo , Compuestos de Amonio Cuaternario/química , Raphanus/efectos de los fármacos , Raphanus/crecimiento & desarrollo , Tioglicolatos/química , Pruebas de ToxicidadRESUMEN
2,2'-Thiodiacetates with their excellent complexing properties may be used as metal extraction agents, fluorescent and superparamagnetic materials, antibacterial and anticancer medical agents, however there are no data concerning the environmental impact of 2,2'-thiodiacetates derivatives and data definying the potential hazard connected with their use. This study describes the ecotoxicity assessment of seven 2,2'-thiodiacetates with non-metallic, alkyl and aryl ammonium cations, which were obtained in an environmentally friendly, solvent-free syntheses. The ecotoxicity of these water soluble compounds was tested in aquatic and benthic environments using luminescent marine bacteria Vibrio fischeri (Microtox® test) and the crustaceans Heterocypris incongruens (Ostracodtoxkit F™), respectively. The antimicrobial and antifungal activity against Trichoderma viridis, Aspergillus niger, Rhizoctonia solani and Escherichia coli was also investigated. The results showed how structural changes within ammonium cations themselves influence ecotoxicity: the QASs with alkylammonium cations exhibited a similar, rather low toxicity both to Vibrio fischeri and Heterocypris incongruens, and they would not pose a risk to these organisms in case of leakage. Higher toxicity was observed in case of two isoquinolinium salts, however it was rather associated with the heteroaromatic cation, than with the 2,2'-thiodiacetate anion.
Asunto(s)
Acetatos/química , Acetatos/toxicidad , Compuestos de Azufre/química , Compuestos de Azufre/toxicidad , Acetatos/farmacología , Aliivibrio fischeri/efectos de los fármacos , Compuestos de Amonio/química , Animales , Antibacterianos/química , Antibacterianos/farmacología , Antifúngicos/química , Antifúngicos/farmacología , Cationes , Crustáceos/efectos de los fármacos , Sales (Química) , Compuestos de Azufre/farmacologíaAsunto(s)
Enfermedades Óseas/tratamiento farmacológico , Difosfonatos/farmacología , Animales , Enfermedades Óseas/complicaciones , Resorción Ósea/etiología , Resorción Ósea/prevención & control , Difosfonatos/uso terapéutico , Humanos , Osteoblastos/efectos de los fármacos , Osteoclastos/efectos de los fármacosRESUMEN
[formula: see text] A total synthesis of the racemic methyl ester of desepoxy-4,5-didehydromethylenomycin A has been achieved in six steps with an overall yield of 31% starting from diethyl methanephosphonate. The key steps include the Nazarov cyclization of the dienone 7 leading to the alpha-phosphoryl cyclopentenone 8 and the Horner-Wittig reaction of the latter employed for the introduction of the exocyclic methylene moiety.