The 8-methoxy-and &hydroxy-llH-pyrido [2, 3-a]-,-[3, 4a]-,-[4, 3-a]-, and [3, 2-a] carbazoles were synthetized as potential DNA intercalating antitumor drugs. The structure of these compounds was confirmed by'H NMR study including NOE experiments. The DNA binding properties of substituted and unsubstituted (8 4 heterocycles were determined by using their hydrochlorides or methiodides. These derivatives are able to bind to DNA with an affinity ...