Within the flavonoid class of natural products the prenylated sub-class is quite rich in structural variety and pharmacological activity. In the last twenty years a huge number of new structures has been reported, mostly from Leguminosae and Moraceae, with few coming from other genera. The presence, in different forms, of the isoprenoid chain can lead to impressive changes in biological activity, mostly attributed to an increased affinity for biological membranes and to an improved interaction with proteins. Molecules, such as xanthohumol and sophoraflavanone G, while being very structurally simple, show numerous pharmacological applications and are ideal candidates for SAR aimed to the discovery of new drugs. Only recently the biogenesis of these compounds has been more extensively studied and much attention has been focused on the enzymes involved in the modification and transfer of the prenyl unit.

Thermal ring opening of N-[3-(triethoxysilyl)propyl]-2-carbomethoxyaziridine in the presence of C60 produces a fulleropyrrolidine derivative which is then attached covalently to HPLC silica gel. The new chromatographic material is used to investigate binding affinities of potential hosts for the immobilized C60. Exceptionally high size selectivities have been obtained for cyclic oligomeric compounds like calixarenes and cyclodextrins in organic and water-rich media, respectively. A number of rationally designed, helical-shaped peptides bind selectively to the grafted fullerene. The most tightly bound peptide carries two ferrocene moieties at the periphery of a hydrophobic binding cavity complementary in size to C60.

Treatment of (E)-2,4-dimethoxycinnamic acid methyl ester with BF3.Et2O in CHCl3 at room temperature afforded in 75% yield two stereoisomeric C-alkylcalix[4]resorcinarenes, which were shown to be in the 1,2-alternate and flattened-cone configurations

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