title: A biomimetic domino reaction for the concise synthesis of capreomycidine and epicapreomycidine.
abstract: The non-proteinogenic amino acids capreomycidine and epicapreomycidine are constituents of antibiotically active natural products, but the synthesis of these unusual cyclic guanidine derivatives is challenging. The biosynthesis of capreomycidine has therefore been employed as a guideline to develop a concise biomimetic synthesis of both epimeric amino acids. The resulting domino-guanidinylation-aza-Michael-addition reaction provides the most convenient access to these amino acids in racemic form. Attempts to dissect the domino reaction into two separate transformations for a stereocontrolled version of this synthetic approach have also been made. The synthesized didehydro-arginine derivatives with urethane-protected guanidine moieties did not undergo the aza-Michael-addition anymore. These results may have wider implications for the 1,4-addition of guanidines to α,β-unsaturated carbonyl compounds, particularly to didehydro amino acids.
authors.affiliation: Department of Chemistry, Institute of Organic and Biomolecular Chemistry, Georg-August-University Göttingen, Tammannstr. 2, 37077, Göttingen, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Büschleb
authors.forename: Markus
authors.initials: M
authors.lastname: Granitzka
authors.forename: Dietmar
authors.initials: D
authors.lastname: Stalke
authors.forename: Christian
authors.initials: C
authors.lastname: Ducho
mesh_terms: D001120:Arginine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D001688:Biological Products / Q000138:chemical synthesis* / Q000737:chemistry; D032701:Biomimetics; D003500:Cyclization; D008968:Molecular Conformation; D013237:Stereoisomerism
chemical_list: D001688:Biological Products; C463580:capreomycidine; D001120:Arginine