In reaction of 3-dimethylamino-2-(pyridyl-4')acrolein with cyanoacetic acid and malononitrile new derivatives of 3,4'-dipyridyl were obtained. The synthesis of pyridyl-4-cyanoacetaldehyde 2 is also described. One of these compounds (8) showed significant cytostatic activity against transplanted Ehrlich ascites carcinoma and Nemeth-Kellner lymphoma.