Synthetic studies of novel ninhydrin analogs

Ninhydrin is an essential tool in the analysis of amino acids, peptides, and proteins, and the preferred reagent for the detection of latent fingerprints on porous surfaces. The goal of this investigation was to prepare ninhydrin analogs with enhanced chromogenic and fluorogenic properties. Target compounds included structures with extended conjugation and (or) with the presence of sulfur-containing moieties. We have devised general convergent routes for novel heterocyclic and aryl-substituted ninhydrin analogs for use as reagents for amino acid detection.Key words: ninhydrin analogs, synthesis, ketals, Suzuki cross-coupling reactions, Stille cross-coupling reactions.