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Apart from a large amount (ca. 2.0%) of α-bisabolol β-D-fucopyranoside (2a), the aerial parts of the Mediterranean weed Carthamus glaucus afforded an unusual triglyceride (E-2-crotonyl-1,3-distearolylglycerol, 7), two lipophilic flavonoids (6a,b), and a series of bisabolane fucopyranosides variously acylated on the sugar moiety (2b-e) or oxidized on the terpenoid core (3, 4a,b, 5a,b). The fucopyranoside 2a is more soluble in polar media and more versatile in terms of formulation than its aglycone [(-)-α-bisabolol, 1], an anti-inflammatory cosmetic ingredient in current short supply in its natural form. A comparative investigation of the activity of α-bisabolol (1a), the fucopyranoside 2a, and its senecioate 2b on transcription factors involved in inflammation and cancer pathways (NF-κB and STAT-3) showed only marginal activity on NF-κB inhibition for all compounds, while STAT-3 was inhibited potently by the fucoside 2a and, to a lesser extent, also by α-bisabolol. These observations qualify 2a as an easily available compound, both as an apoptotic lead structure and as a potential alternative to natural α-bisabolol (1) for pharmaceutical and/or cosmetic development.

The needles of Taxus wallichiana Zucc. gave the novel oxetane-type taxane diterpenoids 2 and 5, whose structures have been established on the basis of spectroscopic data and chemical reactions. The acidcatalysed rearrangement of 1 0-deacetyl baccatin I I I has been investigated.As part of a study on renewable sources of taxol and related compounds, we reported the isolation of 14-f3-hydroxy-10deacetylbaccatin I11 1 from the needles of the Himalayan yew (Tuxus wullichiunu Zucc.).' Compound 1 can be used as a synthetic precursor of hydroxylated derivatives of taxol,' and this prompted us to investigate further this plant for the presence of additional compounds potentially useful for the synthesis of antitumour taxoids. In the course of these studies, two new taxanes of the oxetane-type (2 and 5) were obtained from fractions less polar than those containing 1. R' R2 R3 R41 BnzH OHOH 2 H H OHOBnz 3 BnzOHH OH (Bnz = benzoyl)