Tanacetum species

A new sesquiterpenoid (317) isolated from the roots of a Turkish plant (Tanacetum species) has been assigned a structure whose biosynthesis may involve... 

Tanacetum species contain mainly sesquiterpenoids and flavonoids, whereas the other terpenoids and phenolic compounds are rarely found. Sesquiterpenoids which are the main constituents of the genus, supposed to be bioactive principles of the plants. Flavonoids and essential oils are also pointed out as active substances in some species. On the other hand, there is a confusion on the systematic position and classification of several species of Asteraceae, therefore chemotaxonomy of the species will help the systematic studies. 

Tanacetum species have been used as remedies in traditional medicine since ancient times in all over the world. Although many species of the genus Tanacetum, such as T. annuum, T. halsamita, T. indicum, T. nubigenum, T. santolinoides, T. vulgare and T. parthenium are used therapeutically around the world the last two are the most studied and the best characterized [8]. 

The main goal of this chapter is to present the chemical constituents and the biological activities of Tanacetum species. 

Tanacetum species contain mainly sesquiterpenoids and flavonoids, whereas the other terpenoids and phenolic compounds are rarely found. Since the importance of sesquiterpenes, sesquiterpene lactones and flavonoids from the chemosystematic point of view, especially the... 

The distribution of the terpenoids will be given in Table 1, and the spectral data of the new compounds isolated first from Tanacetum species will be displayed in Tables 2, 3 and 4. The occurance of the flavonoids in the genus will be presented in Table 5 and their structures in Fig. (1-3). 

Yxmusov et al. worked on the sesquiterpenoids of Tanacetum species in 70 s. They isolated a number of new compounds however, they, sometimes reported only the name of the new compounds with a few data which is impossible to display in the tables. The new sesquiterpenoids tanacin and tachillin were isolated from T. pseudoachillea. Although a few spectral data was given for tachillin, the type and the structure of the sesquiterpenoid is not clear [70], therefore Ae compound could not be placed in the tables. No spectral data was given for pyrethin whose formula presented as 10a-hydroxy-3,4-epoxyguai-ll(13)-en-6,12-olide, Euid isolated from T. parthenifolium, and it was named first pyretine then pyrethrin. In these works the structure of isoridentin was not given as well [57,81]. 

So far, thirteen endemic Tanacetum species, containing mainly sesquiterpene lactones, and flavonoids have been investigated by our group. 

P-Sitosterol and stigmasterol are the common steroids in the genus. So far only few common triterpenes such as friedelin (207), e/ /-fnedelinol (208), a-amyrin (204), P-amyrin (205), a-amyrin acetate (206), taraxasterol (213), lupeyl acetate (209), magnificol (210) were isolated from Tanacetum species. However, T. sinaicum afforded unusual new malabaricane type triterpenoids 3p-acetoxymalabarican-14(26),17E,21-triene (211) and 3-oxo-malabarica-14(26),17E,21-triene (212) (Table 1). 

Table 3. The NMR data of the new terpenoids isolated first from Tanacetum species C 15.10 MHz, 20.15 MHz, 25.18 MHz, MHz, 50-50.75 MHz, 62.9-67.5 MHz, 100-100.6 MHz, not given ME20-d6, C6D6, rCDCIa, CD2Cl2, CP30D, f=CDCl3/CD30D, 25 C, CDCI3/CD3OD, 57 C, Pyridine-ds, not given)...

Tablo 4. Physical and Spectral Data of the New Terpenoids Isolated First from Tanacetum species... 

Flavonoids occured mostly as methyl esters in Tanacetum species. Although methylated flavones, flavonols and agylcones are the main phenolic compounds, glycosides, flavonones, and a few coumarin derivatives are also present in the genus. 

Structure analysis has been revealed that 6-hydroxylation of flavonols and flavones is a common feature in Tanacetum species. Flavonoids isolated from several Tanacetum species are represented in alphabetical order in Table 5 and their structures are shown in Fig. (1-3). 

Table 5. Flavonoids Isolated from Tanacetum Species...

Bioactive princibles of several Tanacetum species are summarized in Table 10. 

Antiinflammatory activity of Tanacetum species is caused by various kind of compoimds, such as sesquiterpenoids, flavonoids and essential oils. 

In a human polymorphonuclear leucocj e-based bioassay, it was determined that acetone extracts of the leaves of four Tanacetum species T. parthenium, T vulgare, T. ptarmiciflorum and T. niveum) inhibit phorbol myristate acetate-induced chemiluminescence of human polymorphonuclear leucocytes [186,187]. Brown et al. investigated the antiinflammatory activity of T. parthenium and a constituent of Ais plant, parthenolide. They suggested that parthenolide is not the only active constituent [187]. Hoult et al have announced that a flavonoid, tanetin is one of the active compounds presented in T. parthenium [156]. 

Antiinflammatory activity of the flavonoids [131,132,141,147,148,156,157] and essential oils [83,150,152,158] isolated from Tanacetum species were also reported. 

In the literature, most of the data about the cytotoxic effects of Tanacetum species are on feverfew T. parthenium) and its major constituent. 

Table 2. The H NMR data of the new terpenoids isolated first from Tanacetum species ( 60 MHz, 2 80 MHz, 3 90 MHz, MOO MHz, 200 MHz, 6 250 MHz, 7 270 MHz MOO MHz 360 MHz , 0 400 MHz ",500 MHz,, J not given Me20-d6,b C6D6,e, CDC13, , CD2Cl2, DMSO-ds iCCU iCDClj+CDjOD, 57°C Pyridine-ds, CDCl3+CD3OD, 25°C -A Acetyl derivative of the compound)...

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