Synthesis of key intermediates leading to 2-iso-oxacephems was carried out starting from L- and D-threonine. As predicted in our previous paper (Tetrahedron Lett. 1995, 36, 8303-8306) all diastereomers of 2-iso-oxacephems can be prepared from the appropriate enantiomers of the amino acid threonine. The absolute configuration of the 2,3- and α-carbon atoms in the β-lactam structure was determined by X-ray crystallographic studies.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry
- Inorganic Chemistry