marizomib and lactacystin

The ubiquitin-proteasome pathway functions as a main pathway in intracellular protein degradation and plays a vital role in almost all cellular events. Various inhibitors of this pathway have been developed for research purposes. The recent approval of bortezomib (PS-341, Velcade, a proteasome inhibitor, for the treatment of multiple myeloma has opened the way to the discovery of drugs targeting the proteasome and other components of the ubiquitin-proteasome pathway.. We review the current understanding of the ubiquitin-proteasome pathway and inhibitors targeting this pathway, including proteasome inhibitors, as candidate drugs for chemical therapy.. Preclinical and clinical data for inhibitors of the proteasome and the ubiquitin-proteasome pathway are discussed.. The proteasome and other members in the ubiquitin-proteasome pathway have emerged as novel therapeutic targets.

Topics: Acetylcysteine; Animals; Antineoplastic Agents; Biological Products; Boronic Acids; Bortezomib; Drug Delivery Systems; Drug Discovery; Humans; Lactones; Neoplasms; Peptides; Protease Inhibitors; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Pyrazines; Pyrroles; Structure-Activity Relationship; Ubiquitin; Ubiquitin-Activating Enzymes; Ubiquitins

Lactacystin and salinosporamide A are fascinating molecules with regard to both their chemical structures and biological activities. These naturally occurring compounds are potent and selective proteasome inhibitors. The molecular structures are characterized by their densely functionalized gamma-lactam cores. The structure and biological properties of these two compounds are attracting the attention of many chemists as challenging synthetic targets. We discuss their synthetic strategies in this review.

Topics: Acetylcysteine; Enzyme Inhibitors; Lactones; Molecular Structure; Proteasome Inhibitors; Pyrroles; Stereoisomerism

The cinnabaramides A-G (1-7) were isolated from a terrestrial strain of Streptomyces as potent and selective inhibitors of the human 20S proteasome. Their chemical and biological properties resemble those of salinosporamide A, a recently identified lead compound from an obligate marine actinomycete, which is currently under development as an anticancer agent. Cinnabaramides F and G (6, 7) combine essential structural features of salinosporamide A and lactacystin and show about equal potency in vitro, with IC50 values in the 1 nM range. The properties and phylogenetic position of the producer organism, the production and isolation of compounds 1-7, their structure elucidation by MS and NMR, and their biological activities are reported. Additionally, an X-ray crystal structure was obtained from cinnabaramide A (1).

Topics: Acetylcysteine; Crystallography, X-Ray; Humans; Lactones; Molecular Conformation; Molecular Structure; Proteasome Inhibitors; Pyrroles; Streptomyces