title: Methods of using click chemistry in the discovery of enzyme inhibitors.
abstract: This protocol describes the step-by-step procedures for the efficient assembly of bidentate inhibitor libraries of a target enzyme, using the so-called 'click chemistry' between an alkyne-bearing core group and an azide-modified peripheral group, followed by direct biological screening for the identification of potential 'hits'. The reaction is highlighted by its modularity, high efficiency (approximately 100% yield in most cases) and tolerance toward many functional groups present in the fragments, as well as biocompatibility (typically carried out in aqueous conditions with small amounts of biocompatible catalysts). The approach consists of three steps: (i) chemical synthesis of alkyne-bearing protein tyrosine phosphatase or matrix metalloprotease core groups and diverse azide-modified peripheral groups; (ii) click chemistry to assemble the bidentate inhibitor libraries; and (iii) direct screening of the libraries with target enzymes using 384-well microplate assays. Following the chemical synthesis of the core and peripheral groups and optimization of the click chemistry conditions (approximately 1 week), steps (ii) and (iii) take 3 d to complete (approximately 1-2 d for library assembly and 1 d for inhibitor screening).
authors.affiliation: Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543, Republic of Singapore.
authors.forename: Rajavel
authors.initials: R
authors.lastname: Srinivasan
authors.forename: Junqi
authors.initials: J
authors.lastname: Li
authors.forename: Su Ling
authors.initials: SL
authors.lastname: Ng
authors.forename: Karunakaran A
authors.initials: KA
authors.lastname: Kalesh
authors.forename: Shao Q
authors.initials: SQ
authors.lastname: Yao
mesh_terms: D001386:Azides / Q000737:chemistry; D001665:Binding Sites; D004791:Enzyme Inhibitors / Q000737:chemistry*; D006877:Hydroxamic Acids / Q000737:chemistry; D061965:Matrix Metalloproteinase Inhibitors; D020782:Matrix Metalloproteinases / Q000138:chemical synthesis; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors / Q000138:chemical synthesis; D054852:Small Molecule Libraries
chemical_list: D001386:Azides; D004791:Enzyme Inhibitors; D006877:Hydroxamic Acids; D061965:Matrix Metalloproteinase Inhibitors; D054852:Small Molecule Libraries; D017027:Protein Tyrosine Phosphatases; D020782:Matrix Metalloproteinases