Metabolites of the Higher Fungi, 30. threo- and erythro-Telfairic Acid and 2,3-Didehydrotelfairic Anhydride from the Fungus Xylaria telfairii†

Three novel metabolites, threo- and erythro-telfairic acid [threo- and eryhro-(1′E,3′E)-2-(4-carboxyhexa-1,3-dienyl)-3-methylsuccinic acid (3a and 3b)] as well as 2,3-didehydrotelfairic anhydride [1′E,3′E)-2-(4-carboxyhexa-1,3-dienyl)-3 methylmaleic anhydride (4)] have been isolated from the culture medium of the fungus Xylaria telfairii Berk. Their structures (apart from the absolute configuration of 3a and 3b) have been elucidated by chemical and physical methods.