Synthesis and biological evaluation of novel flavonols as potential anti-prostate cancer agents.

A library of flavonol analogues was synthesised and evaluated as potential anticancer agents against a human prostate cancer cell line, 22rν1. Compounds 3, 8 and 11 (IC(50) 2.6, 3.3 and 4.0 μM respectively) showed potent cancer cell growth inhibition, comparable to the lead compound 3',4',5'-trimethoxyflavonol (1) (IC(50) 3.1 μM) and superior to the naturally occurring flavonols quercetin (16) and fisetin (22) (both >15 μM). Results indicate that the 3',4',5'- arrangement of either hydroxy (OH) or methoxy (OMe) residues is important for growth arrest of these cells and that the OMe analogues may be superior to their OH counterparts. Compounds 1, 3, 8 and 11 warrant further investigation as potential agents for the management of prostate cancer.