(-)-Xanthorrhizol (1)
isolated from the rhizomes of Curcuma
xanthorrhiza has been transformed to several
bisabolanetype sesquiterpenoids, in a stereoselective manner. 10R- and 10S-10,11-dihydro-10,11-dihydroxyxanthorrhizols (2, 3), ()-curcuquinone (4), ()-curcuhydroquinone (5), helibisabonol A (7) and allylic alcohol 8 have been prepared from
Xanthorrhizol in optically active forms. All the routes involved a Sharpless AD to introduce the
stereogenic centre at C-10.
(-)-Xanthorrhizol (1), the major component of the essential oil of Curcuma xanthorrhiza, is a bisabolanetype sesquiterpenoid containing a stereogenic centre at the benzylic position. It was first isolated in 1970 and its absolute configuration was assigned as R.1 With regards to its bioactivity, it has been shown that xanthorrhizol (1) exhibits antibacterial activity against Streptococcus mutans (MIC = 2 lg/mL).2 Although nine syntheses have been reported for xanthorrhizol,1b,3 the
chemistry of 1 has not been explored fully. Aguilar et al. prepared several simple derivatives of xanthorrhizol, which displayed mild antifungal activity, but did not show
cytotoxic activity towards certain human cell lines.4 Thus, it is of interest to study the chemistry of 1 in order to exploit the readily availability of xanthorrhizol as a precursor for the preparation other useful compounds.
More abstracts about the Chemistry of xanthorrhizol: synthesis of several bisabolane