Synthesis of propranolol mustard as a possible lung-specific antitumor agent.

A nitrogen mustard analog of propranolol was synthesized as a potential lung-specific antitumor agent. Since dl-propranolol concentrates in lung tissue and beta-blocking activity resides only with the l-enantiomer, the d-modification could serve as a lung-directed carrier for a cytotoxic group. Reaction of 1-(1-naphthyloxy)-3-[bis(2-hydroxyethyl)amino]-2-propanol with thionyl chloride resulted in replacement of all three hydroxyl groups with chlorine. The necessary chlorination selectivity was achieved with p-toluenesulfonyl chloride in dimethylformamide solution to provide propranolol mustard, 1-(1-naphthyloxy)-3-[bis(2-chloroethyl)amino]-2-propanol. Both the trichloro compound and propranolol mustard showed reproducible activity against P-388 leukemia. Neither compound was active against the B16 tumor or Lewis lung carcinoma.