Santosh Kumari

Highly Selective Sensing of Li(+) in H2O/CH3CN via Fluorescence 'Turn-on' Response of a Coumarin-Indole Linked Dyad: an Experimental and Theoretical Study.

A coumarin-indole dyad, N-((7-hydroxy-2-oxo-2H-chromen-4-yl)methyl)-1H-indole-2-carboxamide has been synthesized and characterized by 1H-NMR and 13C-NMR. Effect of various metal ions on fluorescent behavior was also studied. The synthesized compound showed remarkable specificity towards Li+ in organo-aqueous medium over other metal ions. Coordination of the compound with Li+ induces a turn-on fluorescence response. The sensor exhibited good binding constant and low detection limit towards Li+. Experimental results have been verified with Density Functional Theory and Time Dependent Density Functional Theory calculations.

Synthesis, Absorption, and Fluorescence Studies of Coumaryl-Labelled Amino Acids and Dipeptides Linked Via Triazole Ring

Fluorophores based on 4-triazolyl, 7-hydroxy-4-triazolylmethyl, 4-O-triazolylmethyl, and 7-O-triazolylmethyl coumaryl-tagged amino acids and dipeptides were synthesized by copper-catalyzed [3 + 2] cycloaddition reaction between azido- or alkynyl-functionalized coumarins with alkynyl- or azido-functionalized amino acid and dipeptides in good-to-excellent yields. Steady-state absorption and the fluorescence properties of the synthesized conjugates were studied. The chemical applicability of these amino acid and peptide-based fluorophores was successfully demonstrated by their linear elongation by further tagging them with appropriate C- or N-terminus amino acid.