Synthesis and in vitro anti-tumor activity of carboranyl levodopa

Abstract Reactions of closo -1-Me-2-Iodobutyl-1,2- closo -dicarborane, 1-Me-2-I(CH 2 ) 4 - C 2 B 10 H 10 , with L -dopa methyl ester can produce carboranyl L -dopa methyl esters in 54% yield in the presence of sodium hydroxide. The appended closo -carboranes can be decapitated with sodium hydroxide in a mixed solvent of ethanol and deionized water to produce highly water-soluble carboranyl levodopa in 64% yield. All the new compounds were characterized by 1 H, 13 C, 11 B-NMR, FT-IR spectroscopy and elemental analysis. The highly water soluble carboranyl levodopa 4 shows promising efficacy of anti-tumors in vitro in the presence of slow neutron beams.