A versatile enantioselective synthesis of barrenazines.
A versatile enantioselective total synthesis of barrenazines A and B has been accomplished from 1,4-butanediol. The key steps of the synthesis are a sequential allylboration/ring-closing metathesis for the construction of the tetrahydropyridine ring and the preparation of a functionalized 4-azidopiperidin-5-one through a stereoselective epoxidation and regioselective ring-opening reaction. The C(2)-symmetrical pyrazine skeleton of barrenazines was prepared by dimerization of the azidopiperidinone, and the carbon side chain was completed by copper-catalyzed reactions using Grignard reagents.
Peña-López
Miguel
M
Departamento de Química Fundamental, Universidade da Coruña, Spain.
Martínez
M Montserrat
MM
Sarandeses
Luis A
LA
Sestelo
José Pérez
JP
D000818:Animals; D002072:Butylene Glycols / Q000737:chemistry*; D002384:Catalysis; D003300:Copper; D003500:Cyclization; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D014561:Urochordata / Q000737:chemistry
D002072:Butylene Glycols; D006575:Heterocyclic Compounds, 3-Ring; C518944:barrenazine A; C518943:barrenazine B; D003300:Copper; C039681:1,4-butanediol