A fluorescent target-guided Paal–Knorr reaction

It has become increasingly apparent that high-diversity chemical reactions play a significant role in the discovery of bioactive small molecules. Here, we describe an expanse of this paradigm, combining a ‘target-guided synthesis’ concept with Paal–Knorr chemistry applied to the preparation of fluorescent ligands for human prostaglandin-endoperoxide synthase (COX-2).