Two novel crown ether compounds, N, iV'-bis (2-hydroxy-5-nitrobenzyl)-4, 13-diazadibenzo- l8-crown-6 (CCE) and N,”-bis (7-hydr0~~ 4-methylcoumarin-8-methylene)-4, 13- diazadibenzo-18-crown-6 (FCE), have been synthesized as potential reagents for the selective extraction and determination of heavy metal ions. Characterizations of the acid- base reactivity and the heavy metal ion-, &on capabilities are reported. Both CCE and ...