Strobilurin

Azoxystrobin is a synthetic analog of naturally occurring strobilurins and oudemansins. The preventative, curative, eradicant, translaminar and systemic properties facilitate control of a wide range of major plant pathogens in many crops... 

For conventional agriculture efficient fungicides for the control of C. purpurea are not yet available. When fungicides are used, application has to be timed before infection has occurred. Strobilurins can lead to an increase in the number and weight of ergots. 

Two new strobilurins O, 113 and P, 114, containing benzodioxepin skeletons, were isolated from the mushroom Mycena galericulata and characterised spectroscopically <00JAN297>. 

Analogs of strobilurine, such as substituted thiazolo[3,2-A][l,2,4]triazoles at C-2, -5, and -6 positions of the heterocyclic skeleton, have been investigated as agrochemical fungicides <1999ELJP909760>. 

By the early 1980s, the in vitro activity of strobilurin A, the compound from Strobilurus tenacellus, and oudemansin A, from Oudemansiella mucida, had been completely characterised13 (Figure 4.23) and the mode of action was known to be the inhibition of electron transfer in complex... 

T. Anke, F. Oberwinkler, W. Steglich and G. Schramm, The Strobilurins-new antifungal antibiotics from the basidiomycete Strobilurus tenacellus, J. Antibiot., 1997, 30, 806-810. 

Strobilurin A, Strobilurin and Myxothiazole new inhibitors of the bci segment of the respiratory chain with an ( )-/l-methoxyacrylate system as common structural elements , FEBS Lett., 1981,132, 329-333. 

Azoxystrobin (P-methoxyacrylate) is one of 1400 synthesized from the lead compound, strobilurin A. 

Kresoxim-methyl is based on the same strobilurin A lead compounds in which variations of the methoxyacrylate moiety produced the methoxyiminoacetate pharmacophore. 

Nuclear magnetic resonance (NMR) spectroscopy, with X-ray analysis, forms the basis for the determination of the structures of most of the compounds discussed in this chapter. H and 13C NMR played a key role in the revision of the structure of the antifungal metabolite strobilurin D 2, which was shown to contain a benzodioxepin moiety rather than epoxide <1999T10101>. 9-Methoxystrobilurin K was also shown to contain a 1,4-benzodioxepin <1997TL7465>. 

Dafemer M, Anke T, Hellwig V, Steglich W, Sterner O (1998) Strobilurin M, Tetrachloro-pyrocatechol and Tetrachloropyrocatechol Methyl Ether New Antibiotics from a Mycena Species. J Antibiot 51 816... 

Coleman RS, Lu X (2006) Total Synthesis of Strobilurin B Using a Hetero-bw-Metallated Pentadiene Linchpin. Chem Commun 423... 

Anke T, Besl H, Mocek U, Steglich W (1983) Antibiotics from Basidiomycetes. XIII Strobilurin C and Oudemansin B, Two New Antifungal Metabolites from Xerula Species (Agaricales). J Antibiot 36 661... 

Sauter H, Steglich W, Anke T (1999) Strobilurins Evolution of a New Class of Active Substances. Angew Chem Int Ed 38 1328... 

P-Methoxyacrylates. This is an important class of commercial fungicides based on a group of natural products, the strobilurins (see Fig. 10), such as strobilurin A and oudemansin A. Strobilurins act by inhibition of mitochondrial respiration. In 1996, the first representatives of this class of fungicide were launched, including azoxystrobin [52], In 1999, the first fluorine-containing strobilurin, trifloxystrobin (Flint ) [53], was launched by Syngenta and later acquired by Bayer for 760 million. 

Fig. 10. Evolution of strobilurin fungicides from their natural products precursors.

Fluoxastrobin (Fandango , Bariton ) [211-213], a new strobilurin fungicide with curative and leaf-systemic activity, was developed by Bayer CropScience, for use as both a seed treatment and a foliar spray to treat a variety of diseases in cereals. Fluoxastrobin initially was submitted for registration as an (E)/(Z) isomer mixture and later changed to the (E)-isomer. 

Kresoxim-methyl BASF Strobilurin type. (Strobilurin)... 

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