Phenolic Compounds from Aerial Parts

There are a number of reports dealing with the phenolic constituents of the aerial parts of Glycyrrhiza species. About thirty new prenylated phenols have been isolated these compounds are not generally found in the underground parts. 

Ingham reported an isoflavan phytoalexin in the leaves of this species 345). The phytoalexin isomucronulatol (273) is produced on inoculation with Helminthosporium carbonum. 

Forty phenolic compounds have been isolated from the aerial parts. We isolated twenty-one phenolic compounds from the aerial parts collected in Heilogjang Province in northeastern China 346-348). Among these, gancaonin A (274) was isolated for the first time as a natural product and fifteen compounds, gancaonins B-E and L-V (275-289) were isolated as new compounds. Among these, gancaonins A (274), B (275), L (279), M (280) and N (281) are prenylated isoflavones. 

Ghisalberti et al. have reported the isolation of two dihydrostilbenes (294 and 295) having a prenyl group and two prenylphenols (296 and 297) from the leaves and terminal branches of G. acanthocarpa (Lindl) J.B. Black collected in Western Australia (358). 

We examined the aerial parts of G. eurycarpa collected in Gansu Province of northwestern China, and isolated a new isoprenoid-substit-uted flavanone, kanzonol S (298), together with thirteen known flavonoids (359). Kanzonol S (298) is the first example of a flavonoid with an ( )-3-acetoxymethyl-2-butenyl group. 

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The leaves and stems of P. niruri plants, cultivated under hydroponic conditions, contained similar kinds of hydrolyzable tannins to those produced in the parent plants collected in Peru. This result demonstrates the profitable use of hydroponics for a good supply of this important medicinal plant. The hydrolyzable tannins observed mainly in the aerial parts (leaf and stem) could not be isolated from its roots. This tissue specific distribution of phenolic compounds (hydrolyzable tannins and flavan-3-ols which were the structural elements of condensed tannins) observed in P. niruri was also interesting, considering the biosynthetic position of secondary metabolites in this plant. 

Curr Pharm Des 10(27) 3419-3429 Rauha JP, Remes S, Heinonen M, Hopia A, Kahkonen M, Kujala T, Pihlaja K, Vuorela H, Vuorela P (2000) Antimicrobial effects of Finnish plant extracts containing flavonoids and other phenolic compounds. Int J Food Microbiol 56(1) 3-12 Razzakov NA, Aripova SF (2004) Confolidine, a new alkaloid from the aerial part of Convolvulus subhirsutus. Chem Nat Compd 40(l) 54-55... 

Myricetin is a phenolic compound isolated from the aerial part of Abel-... 

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