Hepaticae chemosystematics

It is the major object of this review to present the presently known naturally occurring terpenoids and aromatic compounds of the Hepaticae. Furthermore, the biological activity of the isolated compounds and chemosystematics of the Hepaticae are summarized. 

Early studies on the chemistry of the bryophytes have been summarized by Benesova and Herout 86), Hegnauer 141), Huneck 150 —153,156), Martensson and Nilsson 205a), Spencer 303) and Suire 307). A review of heterocyclic compounds found in the bryophytes was also presented (37). Recently, Markham and Porter 199) have reviewed the chemical constituents of the bryophytes their review includes sesquiterpenoids, water soluble flavonoids, lignins, lipids and bibenzyls published prior to 1978, flavonoid chemistry and chemosystematic approaches to the Marchantiales being discussed in detail. In the three years since publication of this review, 121 papers on the chemistry of the Hepaticae have been published. 

More recently, the flavonoid pattern found in the Hepaticae and the Musci has been discussed by Zinsmeister and Mues (348), Chromatographic characteristics of the flavonoids detected in the Hepaticae and a chemosystematic study of the Marchantiales by use of flavonoids have been reported in a recent review (199),... 

Gorham(72< ) reported that lunularin (595) and lunularic acid (598) were found in the Hepaticae, but not in the Musci and the Anthocerotae. Chemical differentiation between the Hepaticae and the Musci is also observed with respect to terpenoids and lipophilic aromatic compounds. The Hepaticae produce mono-, sesqui- and diterpenoids as well as lipophilic aromatic compounds. By contrast neither mono- and sesquiterpenoids nor lipophilic aromatic compounds have been found in the Musci which have been analyzed so far, except for the presence of one kaurane-type diterpene (508) in Saelania species (272). This characteristic difference in chemical constituents is due to the following fact. Most species of the Hepaticae possess oil bodies which contain the terpenoids and the lipophilic aromatic compounds, whereas, the Musci do not contain oil bodies. Terpenoids and aromatic compounds are major constituents of the Hepaticae and can be used as important chemosystematic markers at different taxonomic levels 13a, 19, 21, 25a, 26—29, 33, 34, 45—47, 67, 69, 74, 334). Although flavonoids are not major components of the Hepaticae, these can also be used as chemical markers (187—198, 200—205, 259, 264, 310—312, 328, 329). Taxonomic use of biochemical data for all hierarchical levels of the bryophytes was reviewed by Suire and Asakawa (310—312). The chemosystematics of the Marchantiales were reviewed by Markham and Porter (199). 

Asakawa, Y., R. Matsuda, T. Takemoto, S. Hattori, M. Mizutani, H. Inoue, C. Suire, and S. Huneck Chemosystematics of Bryophytes VII. The Distribution of Terpenoids and Aromatic Compounds in Some European and Japanese Hepaticae. J. Hattori Bot. Lab. 50, 107 (1981). 

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