Abstract: Several new pyrido[2,3,4-kl]acridines were synthesized by reacting naphthoquinone, juglone and cyclohexan-1,3-dione with b,b’-diaminoketones in a biomimetic reaction. The structure of all new compounds (6a, b, 8, 10, 11, 12, 14, 15, 16, 17a, b, 20, 21) was elucidated by NMR and MS spectroscopy. Elecrophilic substitution, mainly nitration, of the various compounds was undertaken and the substitution positions determined. A series of derivatives were prepared and their cytotoxicity towards P-388 mouse lymphoma cells analysed. The most cytotoxic derivatives were found to have IC50’s of 0.1 ug/ml.