Synthesis and biological evaluation of certain alpha,beta-unsaturated ketones and their corresponding fused pyridines as antiviral and cytotoxic agents.

A new series of 3,5-bis(arylidene)-4-piperidones, as chalcone analogues carrying variety of aryl and heteroaryl groups, pyrazolo[4,3-c]pyridines, pyridolo[4,3-c]pyrimidines, and pyrido[4,3-c]-pyridines, carrying an arylidene moiety, and a series of pyrano[3,2-c]pyridines, as flavone and coumarin isosteres, were synthesized and screened for their in vitro antiviral and antitumor activities at the National Cancer Institute (NCI). Compounds 9 and 18 proved to be active against herpes simplex virus-1 (HSV-1), while compound 13 showed moderate activity against human immunodeficiency virus-1 (HIV-1). Compounds 14, 26, 28, 33, and 35 exhibited a broad spectrum antitumor activity. In addition, compounds 26, 33, and 35 proved to be of moderate selectivity toward leukemia cell lines. The pyrano[3,2-c]pyridines heterocyclic system proved to be the most active antitumors among the investigated heterocycles.