Glyco-conjugation in 3-ß-anhydroicaritine.

A convenient method has been developed for the glycol-conjugation in 3-position of ß-anhydroicaritine in a reasonable yield. The structure of the 3-glycosylated ß-anhydroicaritine derivatives was confirmed to be correct by 1H NMR, 13C NMR and HRMS spectrum. These compounds are less soluble than icaritin, but more soluble than icariside II in CCl4. The screening results showed that compounds 12h, 12i and 12j had higher cytotoxicity to HepG2 and MCF-7 at a concentration of 50 µM.

Selective alkylation of ß-anhydroicaritine and their biological evaluation on anticancer.

A convenient and selective alkylation of icaritin has been developed. The methodology involved initial formation of ß-anhydroicaritine (3) under acidic conditions followed by selective methylation at the C-3 position and then alkylation at C-5 position. Several alkylated ß-anhydroicaritine derivatives were synthesised using this methodology. These newly synthesised derivatives, especially the compounds 5b, 5c and 5j, significantly suppressed cell proliferation when tested against cancer cell lines in vitro. Compound 5j (R = Bn) exhibited a competitive inhibition against MCF7 in vivo compared to tamoxifen.