ABSTRACT
Natural products still continue to have an important role as a resource of various biologically active substances. Dereplication is a key process in natural product screening that analyzes the extracts of microbial fermentation broths or plant samples. In this review article, we describe and discuss the analytical techniques of dereplication and related technologies in the following sections: 1. Direct detection from microbial colonies. 2. Ultra high performance liquid chromatography (UHPLC)-MS profiling for library construction. 3. Micro-fractionation to identify active peaks. 4. Quantification of small-amount compounds. 5. Structure identification from small amounts. Using these techniques, the desired compound in the mixture library can be rapidly identified.
Subject(s)
Anti-Bacterial Agents/chemistry , Biological Products/chemistry , Bacteria/chemistry , Chromatography, High Pressure Liquid , DNA Replication , Fermentation , Fungi/chemistry , Gene Library , High-Throughput Screening Assays , Magnetic Resonance Spectroscopy , Mass SpectrometryABSTRACT
Hepatitis C virus (HCV) infection represents a serious health-care problem. Previously we reported the identification of NA255 from our natural products library using a HCV sub-genomic replicon cell culture system. Herein, we report how the absolute stereochemistry of NA255 was determined and an enantioselective synthetic method for NA255 derivatives was developed. The structure-activity relationship of the NA255 derivatives and rat pharmacokinetic profiles of the representative compounds are disclosed.
Subject(s)
Antiviral Agents/chemical synthesis , Citrates/chemistry , Hepacivirus/growth & development , Phenylpropionates/chemistry , Animals , Antiviral Agents/pharmacokinetics , Antiviral Agents/toxicity , Cell Line , Cell Survival/drug effects , Citrates/pharmacokinetics , Citrates/toxicity , Half-Life , Hepacivirus/drug effects , Humans , Phenylpropionates/pharmacokinetics , Phenylpropionates/toxicity , Rats , Stereoisomerism , Structure-Activity Relationship , Virus Replication/drug effectsABSTRACT
A series of benzofuran-based farnesyltransferase inhibitors have been designed and synthesized as antitumor agents. Among them, 11f showed the most potent enzyme inhibitory activity (IC(50)=1.1nM) and antitumor activity in human cancer xenografts in mice.
Subject(s)
Antineoplastic Agents/chemical synthesis , Benzofurans/chemical synthesis , Chemistry, Pharmaceutical/methods , Farnesyltranstransferase/antagonists & inhibitors , Quinolones/chemical synthesis , Animals , Antineoplastic Agents/pharmacology , Benzofurans/pharmacology , Crystallography, X-Ray , Drug Design , Drug Screening Assays, Antitumor , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Farnesyltranstransferase/chemistry , Humans , Inhibitory Concentration 50 , Mice , Neoplasm Transplantation , Quinolones/pharmacology , Structure-Activity RelationshipABSTRACT
The C-4 side chain modification of lead compound 1 has resulted in the identification of a potent and selective Candida albicans N-myristoyltransferase (CaNmt) inhibitor RO-09-4609, which exhibits antifungal activity against C. albicans in vitro. Further modification of its C-2 substituent has led to the discovery of RO-09-4879, which exhibits antifungal activity in vivo. The drug design is based on X-ray crystal analysis of a CaNmt complex with benzofuran derivative 4a. The optimization incorporates various biological investigations including a quasi in vivo assay and pharmacokinetic study. The computer aided drug design, synthesis, structure-activity relationships, and biological properties of RO-09-4879 are described in detail.
Subject(s)
Acyltransferases/antagonists & inhibitors , Antifungal Agents/chemical synthesis , Benzofurans/chemical synthesis , Animals , Antifungal Agents/pharmacokinetics , Antifungal Agents/pharmacology , Benzofurans/pharmacokinetics , Benzofurans/pharmacology , Candida albicans/drug effects , Candida albicans/enzymology , Candidiasis/drug therapy , Drug Design , Drug Resistance, Fungal/genetics , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/pharmacology , Fungal Proteins/antagonists & inhibitors , Inhibitory Concentration 50 , Male , Protein Binding , Rats , Rats, Inbred F344 , Structure-Activity RelationshipABSTRACT
A new series of acid-stable antifungal agents having strong inhibitory activity against Candida albicans N-myristoyltransferase (CaNmt) has been developed starting from acid-unstable benzofuranylmethyl aryl ether 2. The inhibitor design is based on X-ray crystallographic analysis of a CaNmt complex with aryl ether 3. Among the new inhibitors, pyridine derivative 8b and benzimidazole derivative 8k showed clear antifungal activity in a murine systemic candidiasis model.
Subject(s)
Acyltransferases/antagonists & inhibitors , Antifungal Agents/chemical synthesis , Benzofurans/chemical synthesis , Fungal Proteins/antagonists & inhibitors , Animals , Antifungal Agents/pharmacokinetics , Antifungal Agents/pharmacology , Benzofurans/pharmacokinetics , Benzofurans/pharmacology , Candida albicans/drug effects , Candida albicans/enzymology , Disease Models, Animal , Drug Design , Drug Stability , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/pharmacology , Inhibitory Concentration 50 , Mice , Models, Molecular , Structure-Activity RelationshipABSTRACT
Myristoyl-CoA:protein N-myristoyltransferase (Nmt) is a monomeric enzyme that catalyzes the transfer of the fatty acid myristate from myristoyl-CoA to the N-terminal glycine residue of a variety of eukaryotic and viral proteins. Genetic and biochemical studies have established that Nmt is an attractive target for antifungal drugs. We present here crystal structures of C. albicans Nmt complexed with two classes of inhibitor competitive for peptide substrates. One is a peptidic inhibitor designed from the peptide substrate; the other is a nonpeptidic inhibitor having a benzofuran core. Both inhibitors are bound into the same binding groove, generated by some structural rearrangements of the enzyme, with the peptidic inhibitor showing a substrate-like binding mode and the nonpeptidic inhibitor binding differently. Further, site-directed mutagenesis for C. albicans Nmt has been utilized in order to define explicitly which amino acids are critical for inhibitor binding. The results suggest that the enzyme has some degree of flexibility for substrate binding and provide valuable information for inhibitor design.
Subject(s)
Acyltransferases/antagonists & inhibitors , Acyltransferases/chemistry , Candida albicans/enzymology , Enzyme Inhibitors/chemistry , Acyltransferases/metabolism , Amino Acids/chemistry , Amino Acids/metabolism , Binding Sites , Crystallography, X-Ray , Enzyme Inhibitors/metabolism , Imidazoles/metabolism , Models, Molecular , Mutagenesis, Site-Directed , Oligopeptides/metabolism , Protein Conformation , Substrate SpecificityABSTRACT
Modification of the C-2 position of a benzofuran derivative 6 (RO-09-4609), an N-myristoyltransferase (Nmt) inhibitor, has led us to discover antifungal agents that are active in a murine systemic candidiasis model. The drug design is based on the analysis of a crystal structure of a Candida Nmt complex with 2. The optimization has been guided by various biological evaluations including a quasi in vivo assay and pharmacokinetic analysis.
