Faradiol

Tussilago farfara L. Kuan Dong Hua (Colts foot) (flower bud) Faradiol, rutin, hyperin, saponins, taraxanthin, tannins, essential oil.33 Antitussive, expectorant, antiasthmatic, stimulate the medullary center and slowly raise blood pressure. 

Among five triterpenoids isolated from Calendula officinalis flowers, P-amyrin (119), faradiol (232), i /-taraxasterol (238), taraxasterol (239), and lupeol (238), the diol 232 was the most active. It showed a dose-dependent effect with a potency that equals that of indomethacin (5) in the topical anti-inflammatory assay with croton oil [33]. Esterification at C-3 of 232 with a fatty acid reduced the activity by more than 50% [33] consistent with our observation in the TPA-induced assay described above. The anti-inflammatory properties, as determined by croton oil-induced edema of mouse ear, of faradiol-3-O-myristate (233) and its 3-O-palmitate (234), the main components of lipophilic extracts of C. officinalis flowers, were shown to be contribute significantly to the pronounced antiphlogistic activity of the lipophilic extracts of C. officinalis flowers [34]. 

Fig. (5). Inhibitory effect of taraxasterol (239) and faradiol (232) on the promotion of skin papillomas by TPA in DMBA-initiated mice. Starting 1 week after initiation by a single topical application of 50 pg of DMBA, 1 pg of TPA was applied twice weekly. Topical application of 239 (2.0 gmol), 232 (2.0 nmol) and vehicle was performed 30 min before each TPA treatment. Data are expressed as percentage of mice bearing papillomas (A), and as average number of papillomas per mouse (B). = +TPA with vehicle alone O = +TPA with 239 A = +TPA with 232 [85].

Fig. (5) A shows the time dependence of skin tumor formation in the groups treated with DMBA plus TPA with or without 2.0 pM each of taraxasterol (239) and faradiol (232). The first tumor appeared at week 11 in the group treated with DMBA/TPA. In the groups treated with DMBA/TPA and 239, the first tumor appeared at week 13. Of mice treated with DMBA/TPA, 73% were tumor-bearing at week 20, as compared 20% in the group treated with DMBA/TPA and 239. Fig. (5) B shows the average number of tumors per mouse. The group treated with DMBA/TPA produced 7.1 tumors per mouse at week 20, whereas the group treated with DMBA plus TPA and 239 had 1.0 tumor per mouse. The treatment with 232 caused an 80% reduction in the average number of tumors per mouse at week 20. In the group treated with DMBA/TPA and 232, no tumors had appeared at week 20 [85].

Pyrek, J. S. and Baranowska, E. 1973. Faradiol and arnidiol. Revision of structure. Tetrahedron Lett. 11, 809-810... 

Faradiol 3-O-myristate (= Taraxast-20-ene-3p, 16P-diol 3-O-myristate) (triterpene)... 

Two new taraxastenes, heliantriols C (171) and F (172), have been isolated from the flowers of Helianthus annuus and their structures confirmed by correlation with faradiol (173)/ Further studies of the mass spectral fragmentation of 16-oxotaraxastenes have been published. 

A detailed study of the mass spectral fragmentation of 16-substituted tarax-astane derivatives has been published.The full paper concerning the structural revision of faradiol and arnidiol from Compositae flowers has appeared ° (see Vol. 4, p. 218). 3a-Acetoxy-16a-hydroxytaraxast-20(30)-ene (197) has... 

The triterpene-enriched fraction of the supercritical CO2 extract of the dried flowers of Calendula officinalis (Asteraceae) inhibited the croton oil-induced ear edema in mice. Of the identified compounds, the faradiol monoesters, lupeol, F-taraxasterol and a mixture of taraxasterol/ 5-amyrin were tested for their anti-inflammatory activity. Faradiol, obtained by hydrolysis of the extract, was the most active compound. It showed a dose-dependent effect with a potency that equals that of indomethacin at 0.14 fimol/cm2 (48% and 47% edema inhibition, respectively). The esterification of faradiol resulted in a reduction of more than 50% in the activity (only 31% inhibition was observed at 0.14 pmol/cm2), whereas 4/-taraxasterol, a C-16P dehydroxylated derivative of faradiol, was less active (47% inhibition at a dose of 0.28 pmol/cm2) [43]. 

To date, about 25 taraxastanes have been isolated, predominantly from Asteraeeae Representatives inelude (+)-20-Taraxasten-3p-ol (v /-taraxasterol) and (+)-20(30)-taraxasten-3p,16p-diol (amidenediol) from lion s tooth Taraxacum officinale and Arnica montana as well as 20-taraxasten-3p,16p-diol (faradiol) from Arnica mon-tana, Tussilago farfara, Senecio alpinus and gold-bloom Calendula officinalis (all Asteraeeae). 

Phytochemistry Leaves contain bitter glycosides, carotenoids, alkaloids, flavonoids, coumarins, saponins, mucilage, tannins, organic acids, cytosterin, inulin, tussilagin, and vitamin C. Rowers contain rutin, amidiol, faradiol, taraxanthin, stigmasterin, cytosterin, phytosterins, n-heptacosane, tannins, etc. (Tolmachev 1976 Khodzhimatov 1989 Ryu et al. 1999). 

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