Synthesis and antiproliferative activities of thioxoflavonoids on three human cancer cells

Can We Improve Diosmetin Activity? The State-of-the-Art and Promising Research Directions

Diosmetin is a natural substance widely distributed in nature, with documented multidirectional biological effects. The wide spectrum of biological activity of diosmetin gives hope that derivatives of this flavonoid may also be used as drugs or dietary supplements used in many diseases. Modification of the structure may, on the one hand, lead to an increase in biological potency, new biological activity, or an increase in solubility and thus bioavailability. This is an important direction of research because the use of pure diosmetin is limited due to its low bioavailability. This work is an attempt to collect information on the possibility of modifying the structure of diosmetin and its impact on biological activity.

Synthesis and anti-proliferative activities of 5,6,7-trimethoxyflavones and their derivatives

A series of 5,6,7-trimethoxyflavones 1a-1g and their derivatives 2a-2g, 3a-3d, 4 and 5, including the natural products 5,6,7-trimethoxy-4'-hydroxyflavone (1a), 5,6,7,3',4' -pentamethoxyflavone (sinensetin, 1 b), 5,6,7-trimethoxy-3',4'-methyl enedioxy flavone (1c), 5,6,7,3'-tetramethoxy-4,5'-methylenedioxyflavone (1e), 5,6,7, 3',4',5'-hextamethoxyflavone (1 g), 5-hydroxy-3,4,2',3',4'-pentamethoxy chal-cone (2 b), 5,4'-dihydroxy-6,7-dimethoxy flavone (cirsimaritin, 3a) and 5-hydroxy-6,7,3', 4'-tetramethoxyflavone (5-demethylsinensetin, 3 b), 3,5,6,7,3',4'-hexamethoxyflavone (3-methoxysinensetin, 4) and 5'-hydroxy-3,6,7,3',4'-pentamethoxyflavone (5) were synthesized. Their anti-proliferative activity in vitro was evaluated against a panel of four human cancer cell lines (Aspc-1, HCT-116, HepG-2 and SUN-5) by the CTG assay. The results showed that most of the synthetic compounds exhibited moderate to high anti-proliferative activities. In particular, compound 3c possess IC₅₀ (5.30 μM) values below 10 μM against Aspc-1 cells and are worthy of further investigation.