title: Selective reduction of peptide isothiazolidin-3-ones.
abstract: Isothiazolidinones are a rare but potentially important chemical moiety in biochemistry. We report the identification of several thiol, phosphinate, and carbon nucleophiles that form covalent adducts by addition to the sulfenamide sulfur. This reduction is selective for isothiazolidinones over similar peptide disulfides. We synthesized a coumarin-based thioacid nucleophile which shows a marked fluorescence increase after addition to an isothiazolidinone sulfenamide bond. [structure: see text]
authors.affiliation: Sunesis Pharmaceuticals, Inc., 341 Oyster Point Boulevard, South San Francisco, CA 94080, USA. tpshiau@yahoo.com
authors.forename: Timothy P
authors.initials: TP
authors.lastname: Shiau
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Erlanson
authors.forename: Eric M
authors.initials: EM
authors.lastname: Gordon
mesh_terms: D003374:Coumarins / Q000737:chemistry; D005456:Fluorescent Dyes; D009682:Magnetic Resonance Spectroscopy; D063065:Organophosphonates; D010084:Oxidation-Reduction; D010455:Peptides / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013055:Spectrophotometry, Infrared; D013438:Sulfhydryl Compounds; D013455:Sulfur / Q000737:chemistry; D013844:Thiazoles / Q000737:chemistry*
chemical_list: D003374:Coumarins; D005456:Fluorescent Dyes; D063065:Organophosphonates; D010455:Peptides; D013438:Sulfhydryl Compounds; D013844:Thiazoles; D013455:Sulfur