Simple dihydropyridine-based colorimetric chemosensors for heavy metal ion detection, biological evaluation,...

In this study, two novel chemosensors containing dihydropyridine fragment namely; (2E, 2E')-1,1'-(2,6-dimethyl-1,4-dihydropyridine-3,5-diyl)bis(3-(4-(dimethylamino)phenyl)prop-2-en-1-one) (1), (2E,2E',4E,4E')-1,1' -(2,6-dimethyl-1,4-dihydropyridine-3,5-diyl)bis(5-(4-(dimethylamino)phenyl)penta-2,4-dien-1-one) (2) have been synthesized and characterized. The solvatochromic behavior was explored in different solvents of various polarities. The visual detection, as well as UV-Vis and fluorescence measurements were carried out to explore the colorimetric and optical sensing properties of the investigated chemosensors towards various metal ions such as Al³⁺, Cr³⁺, Mn²⁺, Fe³⁺, Co²⁺, Ni²⁺, Cu²⁺, Mg²⁺, Hg²⁺ and Zn²⁺. The chemosensors 1 and 2 have strong detecting abilities, with excellent sensitivity and selectivity for Cu²⁺ and Fe³⁺, respectively, over the other metal ions. The chemosensors were totally reversible upon addition of EDTA to the formed complexes and displayed a turn on-off-on fluorescence response based on an effect of chelation-quenching fluorescence. The antioxidant activities of the investigated chemosensors were assessed. They were examined in-silico for their capacity to block the Akt signaling pathway, which is involved in cancer proliferation with interpreting their pharmacokinetics aspects. Furthermore, in-vitro antitumor evaluation against a panel of cancer cell lines for the investigated chemosensors has been examined. Conclusively, chemosensor 1 was more effective at scavenging free radicals and as an anticancer agent and could be exploited as a therapeutic candidate for cancer therapy than chemosensor 2 due to its potential inhibition of Akt protein.