Microwave-Assisted Synthesis and Antitumor Activity of Salicyl Acyloxy Phosphonate Derivatives

Twelve new salicyl acyloxy phosphonate derivatives were synthesized via microwave-assisted reactions of salicylic acid with alpha-hydroxyphosphonate in DCC/DMAP. The structures of the products were confirmed by elemental analysis, IR, H-1 NMR and C-13 NMR data. The suitable synthetic conditions were as follows: in 15 mL of CH2Cl2 with power 800 W at room temperature for 3.5 h. The cytotoxic activities of all compounds on A-549, SGC-7901, HEp-2 and EC-109 in vitro were evaluated by using an 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) method, and some of them showed good antitumor activity. Among the active compounds, espectively, compound 2f had better inhibition effect on HEp-2 cells growth [IC50=(13.9 +/- 0.6) mu mol/L], the IC50 values of compound 2k was (8.5 +/- 0.9) mu mol/L against EC-109 cells, similar to cisplatin [IC50=(5.9 +/- 1.0) mu mol/L].