Facile syntheses and rearrangements of peptide derived β-lactams
摘要:
Stereoselective aldol condensation of a 4,5-diphenyl-oxazolin-2-one (Ox) glycine provided alpha-amino-beta-hydroxy acid 4, which, after coupling with phenylglycine derivatives, was directly cyclized to beta-lactams. Ozonolysis cleaved both the Ox and isopropylidene groups and initiated a Chapman rearrangement to the corresponding alpha-benzamido-beta-acyl-2-azetidinone 8. Subsequent reduction induced a diastereoselective rearrangement to the corresponding gamma-lactone 13.
Facile syntheses and rearrangements of peptide derived β-lactams
摘要:
Stereoselective aldol condensation of a 4,5-diphenyl-oxazolin-2-one (Ox) glycine provided alpha-amino-beta-hydroxy acid 4, which, after coupling with phenylglycine derivatives, was directly cyclized to beta-lactams. Ozonolysis cleaved both the Ox and isopropylidene groups and initiated a Chapman rearrangement to the corresponding alpha-benzamido-beta-acyl-2-azetidinone 8. Subsequent reduction induced a diastereoselective rearrangement to the corresponding gamma-lactone 13.