Medicinal nitro-compounds. Part II. Search for ortho-interactions in tumour-inhibitory 2,4-dinitrophenylaziridines

The 1-(2,4-dinitrophenyl)aziridines (1) and (2) behave as alkylating agents and undergo ring-opening under a range of mild conditions. With organic acids in toluene, 1-(2,4-dinitrophenyl) aziridine (1) yields esters of 2-(2,4-dinitroanilino)ethanol (7)-(13). In strong acids (without solvent) the esters are accompanied by polymer (18). 5-(Aziridin-1-yl)-2,4-dinitrobenzamide (CB 1954) (2) similarly yields esters (14) or (15) in acetic or propionic acids, but polymer (19) in formic acid. Ring opening of the aziridine (1) in mineral acids, in alcohols containing acids, or in alcohols containing alkyl iodides is influenced by the nucleophilicity of the attacking reagent. A series of ethylenediamines (28)-(33) was prepared from the aziridines (1) and (2) and amines without a catalyst being present, but in pyridine, or 3- or 4-aminopyridine, the aziridine (1) afforded polymer (18). The aziridine (1) on acidic or basic alumina in boiling toluene afforded a product identified as bis-[2-(2,4-dinitroanilino)ethyl] ether (35) on the basis of its spectroscopic properties, whereas photolysis in methanol led to ring opening and formation of N-(2-methoxyethyl)-2,4-dinitroaniline (26).