Anticancer and immunomodulatory activities of novel 1,8-naphthyridine derivatives.

A number of 1,8-naphthyridine derivatives (22-62) have been synthesized and screened for their in vitro cytotoxicity against eight tumors and two non-tumor cell lines. Halogen substituted 1,8-naphthyridine-3-caboxamide derivatives showed potent activity with compound 47 having IC(50) of 0.41 and 0.77 microM on MIAPaCa and K-562 cancer cell lines, respectively while, compound 36 had IC(50) of 1.19 microM on PA-1 cancer cell line. However, one of the unsubstituted 1,8-naphthyridine-C-3'-heteroaryl derivative 29 showed potent cytotoxicity with IC(50) of 0.41 and 1.4 microM on PA-1 and SW620 cancer cell lines, respectively. These compounds were also evaluated for anti-inflammatory activity as suggested by downregulation of proinflammaotory cytokines.