Studies on the Utilization of Metal Chelates. XV.

Diethylenetriaminepentaacetic acid (DTPA) dianhydride was treated with five alcohols (C8C16) to give new five chelating agents, DTPA-dialkyl esters.The equivalent reaction between the chelating agents and several metal ions, gave the corresponding 1 : 1 metal.chelates in good yields.These metal chelates and sodium salts of the chelating agents were found to be more soluble in organic solvents than those of DTPA-monoalkyl esters which have been reported in previous paper, and to have good surface-active properties, especially dispersing power.