Isodidymic Acid, a New Dibenzofuran from the Lichen Cladonia didyma
The dibenzofuran isodidymic acid (3-hydroxy-7-methoxy-9-pentyl-1-propyl-dibenzofuran-2-carboxylic acid has been synthesized and shown to co-occur with barbatic acid, subdidymic acid and condidymic acid in Cladonia didyma.
Chester, Douglas O.,Elix, John A.,Kennedy, John M.
p. 1759 - 1764
(2007/10/02)
Naturally Occurring Dibenzofurans. Part 6. Synthesis of Didymic Acid
The synthesis of the lichen dibenzofuran didymic acid (1) (3-hydroxy-7-methoxy-1-pentyl-9-propyldibenzofuran-2-carboxylic acid) by intramolecular Ullmann coupling of methyl 5-bromo-4-(2-bromo-5-methoxy-3-propylphenoxy)-2-methoxy-6-pentylbenzoate (34) and methyl 5-iodo-4-(2-iodo-5-methoxy-4-nitro-3-propylphenoxy)-2-methoxy-6-pentylbenzoate (32) and appropriate further transformations, is described.