Hydroxycoumarin encapsulated sulfonatothiacalix[4]arene: 1H NMR, steady state fluorescence and theory

•Association constant in 4HC⊂TSCX4 was obtained from Fluorescence, 1H NMR titration.•Large downfield signal for Hb proton of 4HC was observed in 1H NMR spectra.•Insights for hydrogen bonding, CH···π interactions obtained from NCI-RDG analyses.•Stern-Volmer constant for the complex turned out to be 2.19 × 104 M−1.•fluorescence quenching of encapsulated 4HC arises due to static interactions.