Novel beta-lactam antibiotics derivatives: their new applications as gene reporters, antitumor prodrugs and enzyme inhibitors.

Since the antibiotic properties of penicillin were first noticed in the beginning of last century, beta-lactam based antibiotics have been well developed as miracle drugs for the therapy of bacterial infectious diseases in clinics. Recently, these "old" antibiotics and their relevant derivatives have also found new applications as gene reporters, anti-cancer prodrugs and enzyme inhibitors. In this review, we will introduce the latest developments in the study of these new applications based on literatures reported over the last decade. The first section covers the recent developments of beta-lactam antibiotics as drugs against bacteria, the second section briefly discusses the occurrence of bacterial resistance and mechanistic studies of beta-lactam resistance in bacteria, the third section presents the current development of fluorogenic cephalosporin based beta-lactam probes for real-time imaging of gene expression, and the fourth section describes relevant studies on beta-lactam based substrates as anti-tumor prodrugs. Beta-lactam substrates as protease inhibitors will be also described in the fifth section. The final section summarizes future perspectives for beta-lactam antibiotic derivatives as scaffolds in the fields of molecular imaging, drug delivery and enzymatic assays.