Rational design of a near-infrared fluorescent probe for rapid monitoring of carboxylesterase in live cells and drug-induced liver injury mice.

Background: Carboxylesterase (CE) is an important enzyme that mainly exists in liver cells and can catalyze the hydrolysis of esters in a variety of pharmaceuticals and xenobiotics. Real-time and non-invasive imaging of CE is of great significance for the study of CE-related metabolic diseases. Although fluorescence sensing technology is considered a promising candidate, the slow response rate (> 60 min), low sensitivity, and short emission wavelength (<650 nm) of most CE probes limit their practical application.

Palladium-catalysed deaminative/decarboxylative cross-coupling of organoammonium salts with carboxylic acids.

A palladium-catalysed carbon-carbon bond-forming reaction deaminative/decarboxylative cross-coupling of organoammonium salts with carboxylic acids was developed. Under the reaction conditions, polyfluoroaromatic carboxylic acids, propiolic acids and α-cyano benzyl carboxylic acid reacted smoothly with benzyl ammonium salts to produce the corresponding carbon-carbon coupling products in good-to-excellent yields.