A study has been made of the in vitro demethylation of nitrogen mustard and the deethylation of nitrogen mustard and triethylene melamine by rat and rabbit liver preparations.
The in vitro demethylation of nitrogen mustard was comparable to that of benadryl and demerol under similar conditions. The relative amounts of formaldehyde formed from the N-methyl group of nitrogen mustard decreased at higher concentrations.
Enzyme preparations from rat hepatoma “Novikoff” were low in demethylating activity when compared with normal rat liver.
The presence of acetaldehyde was demonstrated when nitrogen mustard was employed as substrate, indicating the detachment of a two-carbon fragment from the molecule. No acetaldehyde could be detected when triethylene melamine was used as substrate.
The possible transformation of the ethyleneimino moiety of TEM to glycine appeared unlikely, since in vivo and in vitro studies with benzoate as acceptor showed negligible or no formation of radioactive hippuric acid following the administration of triethylene-C14-melamine.
This investigation was supported in part by a contract with the United States Atomic Energy Commission (AT (30-1)-1107) and in part by The American Cancer Society (CH-30A) and The Damon Runyon Memorial Fund for Cancer Research (DRIR-42E).