The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Damia Barcelo - One of the best experts on this subject based on the ideXlab platform.
-
analysis of the occurrence and risk assessment of polar pesticides in the llobregat river basin ne spain
Chemosphere, 2012Co-Authors: Marianne Kockschulmeyer, Antoni Ginebreda, Susana Gonzalez, J L Cortina, Miren Lopez De Alda, Damia BarceloAbstract:Contamination of surface waters by pesticides continues to be the focus of concern for water authorities due to the growing evidence of their deleterious effects on aquatic life. In this context, the present work investigates the occurrence of 16 selected pesticides belonging to the classes of triazines, Phenylureas, organophosphates, chloroacetanilides and thiocarbamates in surface waters from the Llobregat River (NE Spain) and some of its tributaries (Anoia and Rubi) and assesses their potential impact on the aquatic organisms by applying a recently developed index, the Short-term Pesticide Risk Index for the Surface Water System (PRISW-1), which takes into account the pesticides concentrations and their overall toxicity against three aquatic organisms (algae, Daphnia, and fish). Chemical analysis, performed by means of a fully automated method based on isotope dilution on-line solid phase extraction–liquid chromatography– electrospray–tandem mass spectrometry (on-line SPE–LC–ESI–MS/MS), revealed diuron and diazinon as the most ubiquitous and abundant compounds with levels up to 818 and 132 ng L 1, respectively. Total pesticide concentrations, which in only 1 out of 66 samples surpassed 500 ng L 1, were higher in the tributaries than in the river but their contribution in terms of mass-loads to the overall pesticide pollution of the Llobregat River was relatively small. Contamination increased downstream of the river and was clearly influenced by rainfall and hence river flow. Application of the PRISW-1 index indicated that, although pesticides levels fulfilled the European Union Environmental Quality Standards (EQS) for surface waters, the existing pesticide contamination poses a low to high ecotoxicological risk for aquatic organisms, that algae and macro-invertebrates are at higher risk than fish, and that the organophosphates diazinon and malathion and the phenylurea diuron are the major contributors to the overall toxicity and therefore the most problematic compounds.
-
use of extraction disks for trace enrichment of various pesticides from river water and simulated seawater samples followed by liquid chromatography rapid scanning uv visible and thermospray mass spectrometry detection
Environmental Science & Technology, 1993Co-Authors: Damia Barcelo, G Durand, Veronique Bouvot, Michel NielenAbstract:C18 Empore extraction disks were used for the isolation and trace enrichment of several pesticides [chlorotriazines (atrazine, simazine, and cyanazine), the atrazine metabolites (deethyl- and deisopropylatrazine), organophosphorus (parathion-ethyl, fenitrothion, fenamiphos, and tetrachlorvinphos), phenylurea (linuron), propioanilide (propanil), and carbamate (carbaryl)] from river water and simulated seawater, at concentration levels of 0.25, 25, and 1000 μg/L.
Didier M Lambert - One of the best experts on this subject based on the ideXlab platform.
-
1 benzhydryl 3 phenylurea and 1 benzhydryl 3 phenylthiourea derivatives new templates among the cb1 cannabinoid receptor inverse agonists
Journal of Medicinal Chemistry, 2005Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:New 1-benzhydryl-3-phenylurea derivatives and their 1-benzhydryl-3-phenylthiourea isosteres were synthesized and evaluated for their human CB1 and CB2 cannabinoid receptor affinity. These compounds proved to be selective CB1 cannabinoid receptor ligands, acting as inverse agonists in a [35S]-GTPgammaS assay. The affinity of 3,5,5'-triphenylimidazolidine-2,4-dione and 3,5,5'-triphenyl-2-thioxoimidazolidin-4-one derivatives, possessing the 1-benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea moiety, respectively, was also evaluated. In conclusion, the 1-benzhydryl-3-phenylurea scaffold seems to be a new interesting template of CB1 cannabinoid receptor inverse agonists.
-
versatile access to benzhydryl Phenylureas through an unexpected rearrangement during microwave enhanced synthesis of hydantoins
Organic Letters, 2003Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Bernadette Norberg, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:[reaction: see text] A new access to benzhydryl-Phenylureas is described. These new interesting urea derivatives were obtained by reaction of substituted benzils with substituted Phenylureas under microwave irradiation. Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover, benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin derivatives, demonstrating that only phenylurea derivatives can result in benzhydryl-Phenylureas under the applied conditions. This new reaction proved to be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.
Giulio G Muccioli - One of the best experts on this subject based on the ideXlab platform.
-
1 benzhydryl 3 phenylurea and 1 benzhydryl 3 phenylthiourea derivatives new templates among the cb1 cannabinoid receptor inverse agonists
Journal of Medicinal Chemistry, 2005Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:New 1-benzhydryl-3-phenylurea derivatives and their 1-benzhydryl-3-phenylthiourea isosteres were synthesized and evaluated for their human CB1 and CB2 cannabinoid receptor affinity. These compounds proved to be selective CB1 cannabinoid receptor ligands, acting as inverse agonists in a [35S]-GTPgammaS assay. The affinity of 3,5,5'-triphenylimidazolidine-2,4-dione and 3,5,5'-triphenyl-2-thioxoimidazolidin-4-one derivatives, possessing the 1-benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea moiety, respectively, was also evaluated. In conclusion, the 1-benzhydryl-3-phenylurea scaffold seems to be a new interesting template of CB1 cannabinoid receptor inverse agonists.
-
versatile access to benzhydryl Phenylureas through an unexpected rearrangement during microwave enhanced synthesis of hydantoins
Organic Letters, 2003Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Bernadette Norberg, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:[reaction: see text] A new access to benzhydryl-Phenylureas is described. These new interesting urea derivatives were obtained by reaction of substituted benzils with substituted Phenylureas under microwave irradiation. Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover, benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin derivatives, demonstrating that only phenylurea derivatives can result in benzhydryl-Phenylureas under the applied conditions. This new reaction proved to be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.
Jacques Poupaert - One of the best experts on this subject based on the ideXlab platform.
-
1 benzhydryl 3 phenylurea and 1 benzhydryl 3 phenylthiourea derivatives new templates among the cb1 cannabinoid receptor inverse agonists
Journal of Medicinal Chemistry, 2005Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:New 1-benzhydryl-3-phenylurea derivatives and their 1-benzhydryl-3-phenylthiourea isosteres were synthesized and evaluated for their human CB1 and CB2 cannabinoid receptor affinity. These compounds proved to be selective CB1 cannabinoid receptor ligands, acting as inverse agonists in a [35S]-GTPgammaS assay. The affinity of 3,5,5'-triphenylimidazolidine-2,4-dione and 3,5,5'-triphenyl-2-thioxoimidazolidin-4-one derivatives, possessing the 1-benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea moiety, respectively, was also evaluated. In conclusion, the 1-benzhydryl-3-phenylurea scaffold seems to be a new interesting template of CB1 cannabinoid receptor inverse agonists.
-
versatile access to benzhydryl Phenylureas through an unexpected rearrangement during microwave enhanced synthesis of hydantoins
Organic Letters, 2003Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Bernadette Norberg, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:[reaction: see text] A new access to benzhydryl-Phenylureas is described. These new interesting urea derivatives were obtained by reaction of substituted benzils with substituted Phenylureas under microwave irradiation. Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover, benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin derivatives, demonstrating that only phenylurea derivatives can result in benzhydryl-Phenylureas under the applied conditions. This new reaction proved to be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.
Gerhard K E Scriba - One of the best experts on this subject based on the ideXlab platform.
-
1 benzhydryl 3 phenylurea and 1 benzhydryl 3 phenylthiourea derivatives new templates among the cb1 cannabinoid receptor inverse agonists
Journal of Medicinal Chemistry, 2005Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:New 1-benzhydryl-3-phenylurea derivatives and their 1-benzhydryl-3-phenylthiourea isosteres were synthesized and evaluated for their human CB1 and CB2 cannabinoid receptor affinity. These compounds proved to be selective CB1 cannabinoid receptor ligands, acting as inverse agonists in a [35S]-GTPgammaS assay. The affinity of 3,5,5'-triphenylimidazolidine-2,4-dione and 3,5,5'-triphenyl-2-thioxoimidazolidin-4-one derivatives, possessing the 1-benzhydryl-3-phenylurea and 1-benzhydryl-3-phenylthiourea moiety, respectively, was also evaluated. In conclusion, the 1-benzhydryl-3-phenylurea scaffold seems to be a new interesting template of CB1 cannabinoid receptor inverse agonists.
-
versatile access to benzhydryl Phenylureas through an unexpected rearrangement during microwave enhanced synthesis of hydantoins
Organic Letters, 2003Co-Authors: Giulio G Muccioli, Johan Wouters, Jacques Poupaert, Bernadette Norberg, Wolfgang Poppitz, Gerhard K E Scriba, Didier M LambertAbstract:[reaction: see text] A new access to benzhydryl-Phenylureas is described. These new interesting urea derivatives were obtained by reaction of substituted benzils with substituted Phenylureas under microwave irradiation. Phenylthiourea, when reacted with benzil, gave 3-phenyl-thiohydantoin. Moreover, benzylurea, as phenethylurea, gave the corresponding 3-substituted hydantoin derivatives, demonstrating that only phenylurea derivatives can result in benzhydryl-Phenylureas under the applied conditions. This new reaction proved to be an easy access to substituted 1-benzhydryl-3-phenyl-ureas.