Prelunularic acid in liverworts

Prelunularic acid, the first example of an intermediate with a ‘pre-aromatic’ structure in the phenylpropanoid-polymalonate pathway, was isolated from suspension-cultured cells of Marchantia polymorpha. Its structure, including its absolute configuration, was assigned on the basis of spectral properties, direct conversion into lunularic acid, and CD measurements on the bis(p-dimethylaminobenzoate) of the methyl ester. Prelunularic acid was also detected in several liverworts of Marchantiales and Jungermanniales, and appears to be the immediate precursor of lunularic acid instead of the previously postulated hydrangenol or hydrangeic acid.