Photochemically activated antiviral halogenated 1,8-naphthalimides: Synthesis of N,N′-BIS-{2-[(5-bromo-2-[1-14C]hexyl-1H-benz[DE]isoquinolin-1,3(2H)-dion-6-YL)amino]ethyl}hexanediamide

The synthesis of N,N'-bis-(2-[(5-bromo-2-[1-C-14]hexyl-1H-benz[de]isoquinolin-1,3(2H)-dion-6-yl)amino]ethyl)hexanediamide from 1-[1-C-14]-hexylamine and 4-chloro-1,8-naphthalic anhydride is described. The anhydride is first converted to the 4-chloro-N-[1-C-14]hexyl-1,8-naphthalimid (2) by condensation with 1-[1-C-14]-hexylamine, and the chlorine is then displaced with ethylenediamine to give the 4-(2-aminoethylamino-N-[1-C-14]hexyl-1,8-naphthalimide (3). Coupling of this monomeric naphthalimide with adipoyl chloride affords the dimeric naphthalimide (4) which is brominated regiospecifically with elemental bromine in carbon tetrachloride to afford the title compound (5).