Synthesis And Evaluation Of Flavone 7-alkoxyphosphoramidate Derivatives

Flavonoids,as natural polyphenolic compounds with antitumor activity,is limited in clinical application by poor absorption,metabolism and bioavailability in the body.In this study,taking advantage of phosphoramidate produg modification techniques,which is capable of improving the metabolic processes of the parent compound in vivo,the hydroxy groups of the flavonoids were modified to improve the bioavailability and antitumor activity their ability.In this dissertation,the hydroxyl groups at different positions of chrysin and daidzein were modified by phosphorylation with four different amino acid substituted phosphoramidates and four different amino acid substituted alkoxyphosphoramidates.17flavonoid phosphoramidates were obtained and unreported compounds were fully characterized by 1D NMR(¹H NMR,¹³C NMR,³¹P NMR),2D NMR?¹H-¹H COSY,HSQC and HMBC?and HRMS.The anti-proliferative activity of 17 flavonoid phosphoramidates against liver cancer cells HepG2 cells?liver cancer cells?,MCF7 cells?breast cancer cells?,as well as L-O₂ cells?normal liver cells?were evaluated by MTT assay.Among all the tested compounds,L-valine modified chrysin 7-phosphoramidate 3b(MCF7,IC₅₀=18.6±1.7?M;HepG2,IC₅₀=21.1±2.6?M;L-O₂,IC₅₀>100?M),L-alanine Modified daidzein 7-alkoxyphosphoramidate 14d(MCF7,IC₅₀=6.0±0.2?M;HepG2,IC₅₀=2.6±0.2?M;L-O₂,IC₅₀>100?M)and L-alanine Modified 7-hydroxyethyl daidzein-4'-phosphoramidate 16(MCF7,IC₅₀=4.3±0.1?M;HepG2,IC₅₀=29.2±3.6?M;L-O₂,IC₅₀>100?M)demonstrated potent activity.The results of Annexin V-FITC/PI showed that the percentage of later apoptosis in HepG2 cell lines treated with 14d was 10.1%.In the caspase 3 activity test,we can also conclude that14d had induced HepG2 apoptosis considering the 1.24-folds increase of caspase 3 in HepG2cell after 14d treatment compared with the control.In the assay for Hsp60 inhibitory activity,14d can effectively inhibit the activity of Hsp60 and may induce apoptosis by inhibiting the Hsp60 activity.Compared with the chrysin phosphoramidate derivatives,the anti-tumor effect of the daidzein phosphoroamidates was overall better.The modified compounds?except 9c,9d?exhibited a good selectivity for HepG2 cells in the present of L-O₂cells.The ratio of IC₅₀?HepG2 cells/L-O₂ cells?reached to 38 in the case of 14d.