A novel fluorometric chemosensor based on imidazo[4,5-b]phenazine-2-thione for ultrasensitive detection and separation of Hg2+ in aqueous solution

We synthesize and develop 1,3-dihydro-2H-imidazo[4,5-b]phenazine-2-thione as a ratiometric chemosensor for recognition of Hg²⁺ in DMSO/H₂O (v/v = 9:1) binary solution. We rationally introduce the phenazine imidazole group as fluorophore and the thione moiety as recognition site to bind Hg²⁺. Interestingly, the chemosensor shows ultrasensitive response for Hg²⁺ and the lowest limit of detection is 0.167 nM. In addition, it can also separate Hg²⁺ from aqueous solution with excellent ingestion capacity, and the adsorption ratio is up to 96%. Furthermore, ion test strips based on the chemosensor are fabricated to conveniently and efficiently detect Hg²⁺.

K2CO3 Promoted Cascade Reaction for the Preparation of 1H-Imidazol-4- yl-1-amine Derivatives

: A K2CO3 promoted efficient one pot two-step method for the preparation of 1H-imidazol-4- yl-1-amine derivatives has been developed. A series of second amines with an imidazole group were obtained with 56%-91% yields by the K2CO3 promoted amination of acetates and nitrogen deprotection of the imidazole process.

Self-assembled supramolecular structures of O,N,N′ tridentate imidazole–phenol Schiff base compounds

Three imidazole-derived Schiff base compounds comprising an N-methyl imidazole group coupled to a phenol ring through an imine bond were synthesised. The solid state and solution state supramolecular structures as well as energetics are explored.

The tripeptide GHG as an unexpected hydrogelator triggered by imidazole deprotonation

The tripeptide glycyl-histidyl-glycine (GHG) self-assembles into long, crystalline fibrils forming a strong hydrogel (G′ ∼ 50 kPa) above a critical concentration of 40 mM upon the deprotonation of its imidazole group.