ABSTRACT
Previously, we have evaluated several pyrido[1,2-a]benzimidazoles (PBIs) as potential antineoplastic agents. Among them, NSC 649900 and NSC 682011 revealed good antineoplastic activity against some cell lines of clinically isolated human tumors. For further structure-activity relationship (SAR) studies we report here the synthesis and antineoplastic evaluation of related series of PBIs with similar haloarylamino (13-18, 23-28), haloarylaminomethylene (29-34) and haloarylazo (35-38) moieties at position 1 or 2. Some of these derivatives revealed notable activity against some tumor cell lines; the highest activity was recorded for the p-fluorophenylamino-3-phenyl-PBI (23, NSC 699944) and its p-chlorophenyl analog (24, NSC 699948). These compounds were selected by the NCI for further testing in a new in vivo anticancer hollow fiber assay.