A chromogenic cephalosporin for β-lactamase inhibitor screening assays.

Production of β-lactamases is the primary mechanism of antibiotic resistance employed by gram-negative pathogens. Chromogenic β-lactams are important reagents for detection and assay of β-lactamases, but limited commercial availability and exorbitant pricing of these compounds are prohibitive. Here we describe a straightforward synthesis of a chromogenic cephalosporin for β-lactamase assay that gives an overall yield of 74%.