Abstract

SAEED, Aamer  and  EHSAN, Somia. Synthesis of (±)-kigelin. J. Braz. Chem. Soc. [online]. 2005, vol.16, n.4, pp. 739-742. ISSN 0103-5053.  http://dx.doi.org/10.1590/S0103-50532005000500010.

A simple synthesis of racemic 8-hydroxy-6,7-dimethoxy-3-methyl-3,4-dihydroisocoumarin or kigelin, a metabolite of Aspergillus terreus and Kigelia pinnata, exhibiting several bioactivities, is described. 3,4,5-Trimethoxyhomophthalic acid was refluxed with acetic anhydride in dry pyridine to afford 2,3,4-trimethoxy-6-(2-oxopropyl)benzoic acid. Reduction of the latter followed by cyclodehydration yielded 6,7,8-trimethoxy-3-methyl-3,4-dihydroisocoumarin which on regioselective demethylation furnished the (±)-kigelin.

Keywords : dihydroisocoumarin; Kigelia pinnata; Aspergillus terreus.