ENZYMIC AND NONENZYMIC TRANSFORMATIONS OF CHORISMIC ACID AND RELATED CYCLOHEXADIENES

1. 1. The thermal decomposition of chorismic acid has been studied. When chorismic acid is heated at 100° for 10 min in 0.05 M HCl, the main products are 4-hydroxybenzoic, phenylpyruvic and 3,4-dihydro-3,4-dihydroxybenzoic acids. Heating chorismic acid in 1 M HCl results in the formation of 4-hydroxybenzoic, phenylpyruvic and 3-hydroxybenzoic acids and heating in 1 M NaOH yields 4-hydroxybenzoic, 4-hydroxyphenyllactic and 3-(1′-carboxyvinyloxy)benzoic acids. 2. 2. The isolation, identification and properties of 3,4-dihydro-3,4-dihydroxybenzoic acid and 3-(1′-carboxyvinyloxy)benzoic acid are described in detail. The absolute stereochemistry of the former compound was determined from the tartaric acid obtained following ozonolysis. 3. 3. The enzymic and nonenzymic transformations of chorismic acid and related cyclohexadienes are summarised. © 1969.