
%0 Journal Article
%A Elix, JA 
%A Jenie, UA 
%A Parker, JL 
%T A Novel Synthesis of the Lichen Depsidones Divaronic Acid and Stenosporonic Acid, and the Biosynthetic Implications
%J Australian Journal of Chemistry
%D 1987/08/01
%V 40
%N 8
%P 1451-1464
%K 
%R https://doi.org/10.1071/CH9871451
%U https://www.publish.csiro.au/paper/CH9871451 
%X The depsidones divaronic acid (24) (8-hydroxy-3-methoxy-1,6-dipropyl-11- oxo -11H- dibenzo [ b,e ][1,4]dioxepin-7-carboxylic acid) and stenosporonic acid (25) (8-hydroxy-3-methoxy-6-pentyl-l-propyl-ll-oxo-l1H-dibenzo[ b,e ][1,4]dioxepin-7-carboxylic acid) have been prepared by unambiguous synthesis, and have been shown to cooccur with colensoic acid, atranorin and chloroatranorin in the lichen Paraparmelia mongaensis. The syntheses employed a novel biomimetic-type approach which involved a Smiles rearrangement of a precursor meta-depside in the key step. This rearrangement has important biosynthetic implications and may account for the natural occurrence of isostructural depside-depsidone pairs. 
