Pyrenophora avenae

Pyrenophorin (9) is a bis lactone antibiotic produced by the microorganism Pyrenophora avenae. Diolide 9 is a head-to-tail dimer of a 7-hydroxy-2-ene-4-one carboxylic acid with methyl groups appended to the diolide ring. Retrosyn-thetically, the central strategy employed in almost all approaches is lactonization of the appropriate monomeric hydroxy acid to the diolide. 

Magnus, A.H. 1970. Mercury-tolerance in Pyrenophora avenae in Norway. Meldinger Norges Landbrukshoyskle, 49, 1-8. 

Oats Leaf spot, seedling blight Septoria tritici) Pyrenophora avenae... 

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