First synthesis and biological evaluation of novel spin-labeled derivatives of deoxypodophyllotoxin.

Deoxypodophyllotoxin inhibits tubulin polymerization and induces cell cycle arrest at G2/M, followed by apoptosis. In order to find compounds with superior bioactivity and less toxicity, a series of spin-labeled derivatives of deoxypodophyllotoxin were synthesized by reacting 4'-demethyl-4-deoxypodophyllotoxin (DPPT) with N-(1-oxyl-2,2,6,6-tetramethyl-4-piperidinyloxycarbonyl) amino acids. The cytotoxic activities against three tumor cell lines (HL-60, RPMI-8226, A-549) in vitro and the antioxidative activities in tissues of Sprague Dawley (SD) rats of target compounds were evaluated, and the results indicated that compounds 11a-h were more potent in terms of cytotoxicities and antioxidative activities than either parent compound DPPT or anticancer drug VP-16.