Mangostins

Nakatani K, Norimichi N, Tsutomu A, Hideyuki Y, Yasushi O. Inhibition of cyclooxygenase and prostaglandin E2 synthesis by -y-mangostin, a xanthone derivative in man-gosteen, in C6 rat glioma cells. Biochem Pharmacol 2002 63 73-79. 

A total of 515 xanthones have been identified in 20 families of higher plants, mainly in the Bonnetiaceae and Clusiaceae families (Vieira and Kijjoa 2005). Mangosteen fruit, a typical southeast Asian fruit, is the characteristic dietary source of xanthones (less than 7-8 mg/100 g FW) (Walker 2007). Mangostin is a C-glucosylxanthone that is also found in by-products of mango at high concentration levels (Barreto and others 2008). 

Professor Yates research, reported in over 200 papers, covered a remarkably wide range. He established the structures of complex natural products, such as mangostin, shellolic acid, haplophytine, and the fecapentaenes. He was successful in synthesizing such complex natural products as gambogic acid, various bridged-ring steroids, and cedrene. 

P-mangostin, y-mangostin, garcinone E, l,5-dihydroxy-2-(3methylbut-2-enyl)-3-methoxy-xanthone and l,7-dihydroxy-2-(3-methylbut-2-enyl) 3-methoxyxanthone (Asai et al., 1995). 

Ethanol extract of the fruit peel of G. mangostana showed potent inhibiting activity against HIV-1 protease the compound responsible was isolated and established as mangostin (Chen et al., 1996). Protostane triterpenes, e.g. garciosaterpenes A, B and C, obtained from methanol extracts of bark and stems of G. speciosa, showed anti-HIV-1 activity (Rukachaisirikul et al., 2003c). 

Sakagami, Y., linuma, M., Piyasena, K.C.N.P. and Dharmaratne, H.R.W. (2005) Antibacterial activity of a-mangostin against vancomycin resistant Enterococci VRE) and synergism with antibiotics. Phytomedicine 12(3), 203-208. 

Wahyuono, S., Astuti, P. and Artama, W.T. (1999) Characterization of a bioactive substance Alpha mangostin isolated from the hull of G. mangostana. Indonesian journal of Pharmacology 1 0(3), 8. 

It is remarkable that, for histamine, very few compounds of plant origin have been found to have JI (or H2, H3, H4) -blocking properties (Fig. 18.17). a-Mangostin [28] is an example, although remarkably this compound (a competitive H, antagonist) does not carry a basic function. A basic tertiary amino group is also absent in cicletanide, an intriguing compound that has a chiral center and in which the antihistaminic activity resides in the levo isomer (Fig. 18.17). Rocastine and temelastine are two other antihistaminic compounds with unusual structures (Fig. 18.12). 

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