Preparation of novel selenapenams and selenacephems by nucleophilic and radical chemistry involving benzyl selenides.
2,2a-Dihydro-1H,8H-azeto[2,1-b][1,3]benzoselenazin-1-one (12), 5-selena-1-azabicyclo[4.2.0]oct-3-en-8-one (13), ethyl 1-aza-7-oxo-4-selenabicyclo[3.2.0]heptane-2-carboxylate (16), and benzoselenopenem (33) can be prepared in 39-85% yield through the intramolecular homolytic substitution of aryl, vinyl or alkyl radicals at the selenium atom in suitably-substituted 4-benzylseleno-beta-lactams, or through intramolecular nucleophilic substitution by the benzylseleno moiety in 4-halo-beta-lactam precursors. Application of this chemistry to the preparation of optically active selenium-containing analogues of beta-lactam antibiotics is also detailed.
Carland
Michael W
MW
School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, University of Melbourne, Victoria, Australia3010. carlhs@unimelb.edu.au
Martin
Robyn L
RL
Schiesser
Carl H
CH
D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000737:chemistry; D001593:Benzyl Compounds / Q000737:chemistry*; D015394:Molecular Structure; D016566:Organoselenium Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D047090:beta-Lactams / Q000737:chemistry*
D000900:Anti-Bacterial Agents; D001593:Benzyl Compounds; D016566:Organoselenium Compounds; D047090:beta-Lactams