Parietinic acid

Deriv Methyl di-O-methylparietinate, yellow needles (CHClj-EtOAc), mp 262-263 °C, by methylation of parietinic acid with dimethyl sulphate-KjCOj in acetone StL Xanthoria parietina (L.) Th.Fr. 

Anthraquinones and xanthones are also important constituents of many lichens. Anthraquinmies such as parietin, parietinic acid, emodin, fallacinol, and fallacinal were shown to have a high antimicrobial effect (Manojlovic et al. 2002). Manojlovic et al. (2010) found that the antimicrobial activity of Uchen Laurera benguelensis is mainly related to the presence of Uchexanthone. 

Polygonum multifolrum Thunb. P. chinensis L. He Shou Wu Huo Tan Mo Cao (Hill buckwheat) (root, stem, leaf) Chrysophenol, emodin, emodin methyl ester, rhein, glycoside rhaphantin, lecithin, parietin, chrysophanic acid, anthron.33-49-54-442 A laxative, detoxicant for boils. Treat neurosis, neurasthenia, insomnia, hypercholesterolemia. 

Xanthoria mand-schurica Erythroglaucin Erythroglaucinic acid Parietin Erythroglaucin Erythroglaucinic acid Parietin Nakano et al. (1972)... 

Manojlovic et al. (2005) reported antifungal activity of the anthraquinone parietin isolated from Caloplaca cerina. A potent fungitoxic compotmd, lecanoric acid, was isolated from Parmotrema tinctorum lichen and tested against the fungus... 

Usnic acid (commercial) Atranorin (commercial) Parietin (X. parietind) Gyrophoric acid Umbilicaria hirsutd) Human ovarian carcinoma A2780 Human colon adenocarcinoma HT-29 Backorova et al. (2012)... 

Usnic acid (commercial) Atranorin (commercial) Parietin (X. parietina) Gyrophoric acid (U. hirsuta) Human ovarian A2780 Human breast MCF-7 Human colon HT-29 Human T cells, Jurkat Human cervix HeLa Human breast SK-BR-3 Human colon wild-type p53 HCT-116 p53+/-t- Human colon p53 null HCT-116 p53-/- Backorova et al. (2012)... 

Babula P, Adam V, Havel L et al (2009) Noteworthy secondary metabolites naphthoquinones— their occurrence, pharmacological properties and analysis. Curr Pharm Anal 5 47-68 Backorova M, Backor M, Mikes J et al (2011) Variable responses of different human cancer cells to the lichen compounds parietin, atranorin, usnic acid and gyrophoric acid. Toxicol In Vitro 25 37 ... 

Lichens have proven a useful source of antiviral agents. Established antiviral properties have been attributed to some specific lichen secondary metabolites including usnic acid, parietin, anthraquinones, hypericin, lichenan, etc. For instance, lichenan, which is widely distributed in lichens, is demonstrated to inhibit the tobacco mosaic vims (Stubler and Buchenauer 1996). 

Most published quantitative data are based on isolation of the compounds, and thus represent minimum values. Colorimetric and spectrophotometric methods for quantitative determination of a few substances (without isolation) have been described. Ramaut et al. (1966) and Rundel (1969) determined usnic acid spectrophotometrically. Laasko and Gustafsson (1952) determined usnic acid as the FeClg-complex, and Jayasankar and Towers (1968) used the reaction product of usnic acid with Ehrlich s reagent for the determination. Determination methods for parietin (Hill and Woolhouse, 1966 Richardson, 1967) and atranorin (Vainshtein and Ravinskaya, 1971)... 

Some secondary metabolites of lichens were also reported to have antiviral effects. Perry and coworkers in 1999 reported the antiviral activity of ( )-usnic acids (50 and 51) against the Poho and Herpes simplex type 1 viruses [63]. The viricidal activity of parietin (3), a secondary metabolite of Teloschistes chrysophthalmus (L.) Th. Fr., was reported against Junin and Tacaribe arena viruses [85]. Tobacco mosaic virus inhibition potential of lichenan (73), a metabolite of many lichens, was also reported in the literature [86]. Usnic acid (50) was also reported to exhibit activity against same viruses as tested for parietin (3) [6] (Table 3). 

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