NSC 5844 is a bis-quinoline with diverse biological activities. It inhibits the growth of P. falciparum strains that are sensitive (D-6) and resistant (W-2) to chloroquine in vitro (IC50s = 17 and 27 nM, respectively) but lacks activity against P. berghei in vivo. NSC 5844 inhibits the growth of MDA-MB-468 and MCF-7 breast cancer cells with GI50 values of 7.35 and 14.80 μM, respectively. It also inhibits 24% of botulinum neurotoxin serotype A light chain (BoNT/A LC) metalloprotease activity at a concentration of 20 μM.