A bifunctional alkylating agent and phenylalanine derivative of nitrogen mustard. Melphalan hydrochloride is converted into highly reactive ethylenimmonium intermediates that induce covalent guanine N7-N7 intra- and inter-crosslinks and alkylation of adenine N3 of DNA. This agent also alkylates RNA and protein structures. As a result RNA transcription and protein synthesis are inhibited, ultimately leading to cell growth arrest and/or death.