Synthesis and phloem mobility of acidic derivatives of the fungicide fenpiclonil

• Published in: Pest management science Vol. 60; no. 11; pp. 1063 - 1072
• Main Authors: Chollet, J.F, Rocher, F, Jousse, C, Deletage-Grandon, C, Bashiardes, G, Bonnemain, J.L
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-11-2004; Wiley; Wiley Subscription Services, Inc
• Subjects: Alkynes; antifungal activity; antifungal properties; Ascomycota - drug effects; Benzaldehydes; biochemical pathways; Biological and medical sciences; Biological Transport; castor beans; Chemical control; chemical reactions; Chemical Sciences; Control; disease control; Eutypa; Eutypa lata; fenpiclonil; Fundamental and applied biological sciences. Psychology; fungal diseases of plants; Fungal plant pathogens; fungicides; Fungicides, Industrial - chemistry; Fungicides, Industrial - metabolism; Hydrogen-Ion Concentration; Life Sciences; mechanism of action; Models, Biological; Pest control; Pesticides; phenylpyrroles; phloem; phloem mobility; physiological transport; Phytopathology. Animal pests. Plant and forest protection; plant pathogenic fungi; Plant Shoots - metabolism; pyrroles; Pyrroles - chemistry; Pyrroles - metabolism; Ricinus - metabolism; Ricinus - microbiology; Ricinus communis; synthesis; systemicity; Vegetal Biology; systemicity; phenylpyrroles; Plant pathogen; Eutypa lata; Pesticides; Mobility; Acidity; Systemic; antifungal activity; Fungicide; Pyrrole derivatives; Fungi; Antifungal agent; Phloem; phloem mobility; Ascomycetes; fenpiclonil; Chemical synthesis; Thallophyta
• ISSN: 1526-498X; 1526-4998
• DOI: 10.1002/ps.906

A series of derivatives of the phenylpyrrole fungicide fenpiclonil was synthesized in which a carboxyl group was present at various sites of this non-phloem-mobile molecule. Using the Kleier model, all these acidic analogues were predicted to be moderately phloem-mobile, especially the N-substituted derivatives. One of these latter molecules, N-carboxymethyl-3-cyano-4-(2,3-dichlorophenyl)pyrrole, exhibited some fungicidal activity on the pathogenic fungus Eutypa lata, and was then tested as a phloem-mobile pesticide in the Ricinus system. The compound was indeed mobile in the sieve tubes and was not degraded to fenpiclonil in the phloem sap under our experimental conditions. Its concentration in the sap was closely correlated to the percentage of the undissociated form of the molecule in the external medium, and was similar under acidic conditions (external pH 4.6-5.0) to that of the herbicide glyphosate.